{"paper_id":"46571332-e5e8-4351-9b70-729fc00fafa6","body_text":"Amiodarone-Induced Thyrotoxicosis and Clinical Risk Factors for Thyrotoxic Crisis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Amiodarone-Induced Thyrotoxicosis and Clinical Risk Factors for Thyrotoxic Crisis Marianna Bystrianska, Adrian Bystriansky, Iveta Wildova, Zuzana Mesarošova, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8816835/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Background Amiodarone-induced thyrotoxicosis (AIT) is a serious complication of long-term amiodarone therapy. Its most severe manifestation is thyrotoxic crisis (TxC), a rare but life-threatening condition associated with high morbidity and mortality. Aim To analyze patients with AIT, identify demographic and clinical parameters, evaluate diagnostic and therapeutic approaches, and determine predictive risk factors for TxC. Methods A retrospective study of 55 consecutive patients with confirmed AIT followed between 2005 and 2024. Baseline characteristics, laboratory findings, thyroid ultrasound, clinical presentation, therapy and outcomes were analyzed. Patients were classified into AIT type I, type II, or mixed type. TxC was diagnosed using the Burch–Wartofsky scoring system. Results The cohort included 45 men (82%) and 10 women (18%), mean age 62.3 ± 9.9 years. Amiodarone was prescribed mainly for atrial fibrillation (78%). Mean duration of therapy until AIT onset was 988 ± 502 days. At diagnosis, mean fT4 was 43.2 ± 18.3 pmol/L and mean TSH 0.017 ± 0.052 mIU/L. Thyroid volume averaged 18.1 ± 8.7 mL, and goiter was present in 47% of patients. AIT types were distributed as follows: type I in 23%, type II in 44%, and mixed type in 33%. Six patients (11%) developed TxC, all men, with higher maximum fT4 (> 74.5 pmol/L), larger thyroid volume (> 19 mL), and more frequent atrial fibrillation with rapid ventricular response. Urgent thyroidectomy was required in 5 of 6 cases with TxC. Conclusion AIT is a clinically important complication of amiodarone therapy. Male sex, younger age, large thyroid volume, high maximum fT4, mixed AIT type, and cardiac decompensation are supposed clinical risk factors for TxC. Early recognition and interdisciplinary management are crucial to improve outcomes. Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Amiodarone remains one of the most effective antiarrhythmic agents, used across a wide range of supraventricular and ventricular arrhythmias. Although its clinical efficacy is well established, its use is limited by a considerable burden of extracardiac adverse effects. Despite extensive efforts to develop safer alternatives, no agent has demonstrated comparable efficacy in routine clinical practice. Expectations for new molecules, including amiodarone substitutes such as dronedarone, celivarone, or budiodarone, have not been fulfilled in clinical practice. Thus, in addition to sophisticated non-pharmacological treatments, amiodarone remains one of the most widely used antiarrhythmic drugs today (1). The pharmacological profile of amiodarone is characterized by multichannel blockade, resulting in prolongation of myocardial repolarization and refractoriness and accounting for its broad clinical use in the management of cardiac arrhythmias. However, its therapeutic efficacy is offset by a substantial risk of extracardiac adverse effects, including pulmonary toxicity, hepatotoxicity, and thyroid dysfunction (2). Althought new molecules like dronedarone, celivarone, and budiodarone have been developed to minimize these adverse effects, clinical studies have not demonstrated their significant advantage over amiodarone. Dronedarone, for instance, was initially developed as a less toxic alternative to amiodarone, but its efficacy in treating atrial fibrillation was lower, and its use is limited due to the risk of hepatotoxicity (3). Celivarone, although promising in preclinical studies, has not shown sufficient efficacy in clinical trials (4). Despite major advances in catheter ablation and implantable cardioverter-defibrillator therapy, amiodarone remains indispensable in contemporary arrhythmia management. Amiodarone-Induced Thyrotoxicosis Amiodarone-induced thyrotoxicosis (AIT) is one of the most feared complications of therapy. It may occur early during treatment, after long-term use, or even following drug discontinuation due to the drug’s high lipophilicity and prolonged biological half-life. According to published data, the incidence of thyrotoxicosis peaks between the second and third year of treatment (5,6). Trip et al. reported AIT in 2.5% of patients after 18 months and in up to 33.5% after 48 months of therapy. The occurrence of AIT appears independent of both the daily and cumulative dose of amiodarone, with a male predominance of approximately 3:1 (6). Type I AIT most commonly arises in the setting of preexisting thyroid disease. Thyrotoxicosis is predominantly triggered by an iodine-induced mechanism and typically occurs in latent Graves’ disease or nodular goiter. Patients usually present with nodular or diffuse goiter (> 15 g) or positive TSH-receptor antibodies. Ultrasound (USG) typically demonstrates structural changes of the thyroid gland with normal or increased vascularity (flow grade I–III) (7,8). Twenty-four-hour radioactive iodine uptake (RAIU) is normal or greater than 8% (1,7,8). Type II AIT occurs in patients without previous structural or functional thyroid disease. USG typically reveals a normal thyroid gland or a small diffuse goiter (≤ 15 g), TSH-receptor antibodies are negative, vascularity is absent (flow grade 0), and RAIU is markedly reduced or absent. The underlying mechanism reflects a cytotoxic effect of amiodarone on thyrocytes with sterile inflammatory changes; interleukin-6 (IL-6) may be elevated (4,9). Mixed AIT is diagnosed when patients exhibit features of both Type I (e.g., nodular or large diffuse goiter, or positive TSH-receptor antibodies) and Type II (reduced vascularity on USG and low RAIU) (8–10). Clinical Manifestation of AIT AIT presents across a spectrum from oligosymptomatic disease to overt thyrotoxicosis; rarely, it progresses to life-threatening thyrotoxic crisis (TxC). In polymorbid cardiac patients receiving beta-blockers or other rate-controlling therapies, classical hyperthyroid signs may be blunted. However, when these patients limited adaptive mechanisms are overwhelmed, AIT can significantly increase their risk of morbidity and mortality. Because of amiodarone’s pharmacokinetics, AIT may develop at any time during therapy or several months after withdrawal. (6,7). Treatment of AIT The treatment of AIT is complex and based on the clinical condition of the patient. Spontaneous remission of the disease is rare and occurs only in cases of mild AIT type II. In accordance with current European Thyroid Association (ETA) recommendations, the primary focus is on early differentiation of the patient's AIT type, which creates a prerequisite for adequate therapy (7,8). Continuation vs discontinuation of amiodarone remains debated. Once AIT is diagnosed, it is logical to discontinue amiodarone therapy because it is directly involved in the pathogenesis of the disease. However, in certain cases, discontinuation of amiodarone treatment represents a complex and serious decision that should be preceded by an interdisciplinary consortium with an individualized risk-benefit assessment. These are mainly cases with severe ventricular, life-threatening tachycardias and multimorbid patients with severe heart failure and high cardiovascular risk (11,12,13). The specific therapeutic management of a patient depends on the type of AIT. Treatment of AIT Type I Type I AIT is characterized by increased thyroid hormone synthesis, making thionamides the treatment of choice. Higher initial doses are recommended compared with other causes of thyrotoxicosis, such as Graves’ disease (7,8,13). Suggested regimens include: thiamazole 30–40 mg/day, methimazole 40–60 mg/day, or propylthiouracil 300–600 mg/day. Dosage and duration should be guided by the clinical course, decline in thyroid hormone levels, and achievement of remission (7,13). Potassium perchlorate (250 mg four times daily) may be added. This drug has been used since the 1950s and competitively inhibits iodine uptake, thereby promoting intrathyroidal iodine clearance. Its use is limited by potential toxicity, including agranulocytosis and aplastic anemia, which may be fatal. The maximum daily dose should not exceed 1 g, and treatment duration should be limited to 30 days (14,15). Clinical remission occurs earlier with combined thionamide–perchlorate therapy than with thionamides alone. Most patients improve within 2–3 months. Average treatment duration is 6–18 months, after which thyrostatics may be tapered (13). If no improvement is observed within 4–6 weeks, glucocorticoids should be added and the diagnosis reconsidered, particularly with regard to mixed AIT (8). Treatment of AIT Type II Type II AIT may present with mild symptoms and occasionally undergo spontaneous remission, though it carries a risk of cardiac deterioration. Its pathophysiology is consistent with destructive thyroiditis; therefore, glucocorticoids are the treatment of choice. Prednisone is recommended at 0.5–0.7 mg/kg/day (average 30–40 mg/day). High doses are typically administered for 4–6 weeks, followed by gradual tapering. With early initiation, the therapeutic response is usually rapid and favorable. Treatment should continue until complete remission, with a mean duration of 2–3 months. Thionamides are not considered first-line therapy for Type II AIT (7,8). Treatment of Mixed AIT In cases of mixed AIT, or when the subtype cannot be clearly defined, combination therapy is recommended. This includes thionamides (40–60 mg/day) and prednisone (40–50 mg/day). Most mixed cases resemble Type II AIT; therefore, corticosteroid administration is essential (7,8). In patients with severe heart failure where rapid remission is required, combined therapy should be initiated regardless of subtype (9,10). Additional Therapies Beta-blockers are indicated in all types of AIT, with nonselective agents preferred due to their additional inhibition of peripheral thyroxine-to-triiodothyronine conversion. Lithium may also inhibit thyroid hormone production and release, but its use is limited by adverse effects such as diabetes insipidus and arrhythmias (8,9). Plasmapheresis can transiently reduce circulating thyroid hormone levels, but its clinical benefit remains controversial. It should be considered only when medical therapy fails and urgent thyroidectomy is planned (7,16). Total thyroidectomy is indicated in when medical therapy is ineffective, when there is a marked reduction in left ventricular ejection fraction associate with cardiac decompensation, when amiodarone reintroduction is required, or in patients with a large goiter causing airway compression (17,18). The procedure results in rapid achievement of euthyroidism, significantly improving prognosis and cardiac status. Surgery may be elective, urgent, or emergency, particularly in the context of thyrotoxic crisis. According to the 2018 European Thyroid Association guidelines, indications for elective thyroidectomy in AIT include: a) definitive treatment of thyrotoxicosis, b) continuation of amiodarone therapy in patients with severe arrhythmias, c) c) adverse effects of AIT therapy (7). Urgent thyroidectomy should be considered in: • progressive heart failure despite optimal medical therapy, especially with severe systolic dysfunction (mortality risk 30–50%), • unstable arrhythmias refractory to medication, • inadequate response to comprehensive medical management. These cases require careful risk–benefit assessment by a multidisciplinary team, including endocrinologists, cardiologists, anesthesiologists, and surgeons (7,8,19). Methodology and Patient Cohort Characteristics For this study, we adhered to the Declaration of Helsinki, 2013, Good Clinical Practice, and obtained approval from the institutional Ethics Review Board of University Hospital F.D. Roosevelt Banska Bystrica (Reference number 17/2024) Slovak Republic. Written informed consent was obtained from all patients involved in the study. The retrospective study cohort consisted of 55 patients with amiodarone-induced thyrotoxicosis (AIT) who were followed up between 2005 and 2024. All consecutive patients with confirmed AIT were included. Patients with other forms of hyperthyroidism or thyrotoxicosis of different etiology were excluded. All patients were diagnosed and treated at the Endocrinology Outpatient Department of the University Hospital F.D. Roosevelt, Banska Bystrica. If the severity of their condition required hospitalization, they were admitted to the II. Department of Internal Medicine, University Hospital F.D. Roosevelt, or to the Department of Cardiology, Slovak Health University, Middle-Slovakian Institute of Heart and Vascular Diseases, Banska Bystrica. After stabilization, patients were followed up in the Endocrinology Outpatient Clinic. Clinical history data were obtained directly from patients and supplemented by hospital records. Each patient underwent initial clinical evaluation, standard laboratory testing, and thyroid USG. Additional diagnostic procedures and specialist consultations were performed as indicated. The differential diagnosis of AIT type was made according to standard diagnostic criteria. The following parameters were evaluated: pre-existing thyroid disease, thyroid autoantibody status, USG morphology and vascularity, presence of nodules. medications administered, and therapeutic response. Thyroid volume was measured by USG using the ellipsoid model. Venous blood samples were collected into serum separation tubes containing a gel separator (4.9 mL). Serum levels of TSH, fT4, anti-TPO, and anti-Tg were determined by chemiluminescent immunoassay (ECLIA) using the DxI 9000 system (Beckman Coulter), while anti-TSH receptor antibodies (TRAb) were measured on the Cobas e 411 analyzer (Roche Diagnostics). Reference laboratory ranges were as follows: free thyroxine (fT4), 7.8–14.4 pmol/L; thyroid-stimulating hormone (TSH), 0.35–5.33 mU/L. Remission of AIT was defined as normalization of fT4 values within the reference range. The frequency of clinical and laboratory follow-ups was individualized according to disease severity. For long-term assessment, patient status was evaluated at the most recent outpatient visit. Statistical Analysis Descriptive statistics were used for quantitative parameters. Normality of distribution was tested using the Shapiro–Wilk test. Homogeneity of variance was assessed with Fisher’s two-tailed test. Depending on distribution, comparisons between groups were performed with either the unpaired t-test or the nonparametric Mann–Whitney U test. Categorical variables were analyzed using Pearson’s χ² test. The correlation analysis was performed using Spearman’s rank correlation test. Statistical significance was defined as p < 0.05. Results are presented as absolute numbers and percentages for categorical variables, and as mean ± standard deviation for continuous variables. Statistical analyses were performed using GraphPad Prism 10. Results The study cohort included 55 patients diagnosed with AIT between 2005 and 2024. The majority were men (n = 45; 82%), while 10 patients were women (18%). The mean age at diagnosis was 62.3 ± 9.9 years. Male patients were significantly younger than female patients (60.8 ± 6.5 vs. 69.0 ± 8.3 years, p < 0.05). The mean follow-up duration was 2.8 years. The mean time to remission with conservative therapy in 46 patients was 106.7 ± 62.1 days, while 9 patients who underwent acute total thyroidectomy reached remission after 72.4 ± 18.3 days. Comorbidities and indications for amiodarone Arterial hypertension was present in all patients (100%). Coronary artery disease was diagnosed in 42% (n = 23), of whom 18% (n = 10) had a history of myocardial infarction. A total of 64% (n = 35) had heart failure, and 20% (n = 11) had an implanted cardioverter-defibrillator (ICD). Diabetes mellitus was present in 18% (n = 10). The main indication for amiodarone therapy was atrial fibrillation (n = 43; 78%). Other indications included ventricular tachyarrhythmias (n = 7; 13%) and frequent ventricular extrasystoles (n = 5; 9%). Table.1 Laboratory and thyroid findings At the time of AIT diagnosis, the mean daily dose of amiodarone was 169.4 ± 29.2 mg, and the mean cumulative dose was 170.0 ± 86.1 g. The average duration of amiodarone therapy before AIT onset was 988.5 ± 502 days. Laboratory evaluation at the time of AIT diagnosis showed a mean serum TSH of 0.017 ± 0.052 mIU/L and a mean fT4 of 43.2 ± 18.3 pmol/L (median 39.3 pmol/L; range: 15.6–90.0 pmol/L). In patients who developed thyrotoxic crisis (TxC), the maximum fT4 concentration reached 74.5 ± 12.6 pmol/L (median 73.7 pmol/L; range 60.5–91.0 pmol/L). The maximum fT4 values in the entire cohort of patients with AIT were 49.5 ± 24.0 pmol/L (median 45.0 pmol/L; range 16.6–124.6 pmol/L). The fT4 concentration alone did not predict the severity of the disease or the development of thyrotoxic crisis. Ultrasonographic evaluation revealed a mean thyroid volume of 18.1 ± 8.7 mL. Goiter was present in 47% of patients (n = 26), more frequently in women (80%) than in men (40%) (p < 0.05). More detailed characteristics of patients with AIT presented in Table.2. In the comparison between male and female patients, a statistically significant difference was observed in the prevalence of goiter, which was present in 8 women (80%) compared with 18 men (40%). Statistically significant differences were also found in body weight and in systolic blood pressure. A weak but statistically significant positive correlation was identified between maximum fT4 levels and heart rate (Spearman’s correlation coefficient rₛ = 0.33, p = 0.014) (graf 1) and non-significant correlation between fT4 levels and heart rate (Spearman’s correlation coefficient rₛ = 0.24, p = 0.076) (graf 2). Types of AIT Based on established diagnostic criteria, patients were classified into three subtypes according to TSH receptor antibody positivity, as well as structural, vascular, and volumetric characteristics of the thyroid gland. Type I AIT was identified in 13 patients (23%), Type II AIT in 24 patients (44%), and mixed AIT in 18 patients (33%). Women were more frequently diagnosed with Type I AIT (50% of women vs. 18% of men), while Type II was more common among men (47% vs. 30%). Mixed forms were present in both sexes but predominated in men (35% vs. 20%). Table 3 . Table 1 Basic characteristics of patients with amiodarone-induced thyrotoxicosis (AIT). Parameter Value Number of patients, n 55 Age, years (mean ± SD) 62.3 ± 9.9 Men, n (%) 45 (82%) Women, n (%) 10 (18%) Age – men (years) 60.8 ± 6.5 Age – women (years) 69.0 ± 8.3 Comorbidities Hypertension, n (%) 55 (100%) Diabetes mellitus, n (%) 10 (18%) Coronary artery disease, n (%) 23 (42%) Prior myocardial infarction, n (%) 10 (18%) Heart failure, n (%) 35 (64%) ICD implanted, n (%) 11 (20%) Indications for amiodarone Atrial fibrillation, n (%) 43 (78%) Ventricular tachyarrhythmias, n (%) 7 (13%) Frequent ventricular extrasystoles, n (%) 5 (9%) Abbreviations: AIT – amiodarone-induced thyrotoxicosis; ICD – implantable cardioverter-defibrillator. Table 2 Clinical, laboratory, and ultrasonographic characteristics at AIT diagnosis by sex. Parameter Men (n = 45) Women (n = 10) p All (n = 55) Duration until AIT (days) 945.3 ± 359.2 1234 ± 896.8 0.340 988.5 ± 502.0 fT4 at diagnosis (pmol/L) 43.4 ± 18.8 42.2 ± 16.9 0.856 43.2 ± 18.3 TSH at diagnosis (mIU/L) 0.016 ± 0.055 0.021 ± 0.042 0.802 0.017 ± 0.052 Thyroid volume (mL) 18.2 ± 9.0 17.9 ± 7.1 0.932 18.1 ± 8.7 Goiter, n (%) 18 (40%) 8 (80%) 0.025 26 (47%) Hospitalized, n (%) 26 (58%) 7 (70%) 0.476 33 (60%) Weight (kg) 90.2 ± 12.8 78.3 ± 13.3 0.011 88.1 ± 13.6 Systolic BP (mmHg) 130.4 ± 13.7 139.5 ± 13.0 0.059 132.0 ± 13.9 Diastolic BP (mmHg) 79.6 ± 9.7 81.5 ± 8.8 0.575 80.0 ± 9.5 Heart rate (/min) 88.0 ± 22.8 85.8 ± 10.7 0.649 87.6 ± 21.0 AF on ECG, n (%) 28 (62%) 7 (70%) 0.463 35 (64%) Abbreviations: AIT – amiodarone-induced thyrotoxicosis; USG – ultrasonography; fT4 – free thyroxine; TSH – thyroid-stimulating hormone; BP – blood pressure; AF – atrial fibrillation; ECG – electrocardiogram. Table 3 Distribution of AIT types AIT type Men (n = 45) Women (n = 10) All (n = 55) Type I, n (%) 8 (18%) 5 (50%) 13 (23%) Type II, n (%) 21 (47%) 3 (30%) 24 (44%) Mixed type, n (%) 16 (35%) 2 (20%) 18 (33%) Abbreviations: AIT – amiodarone-induced thyrotoxicosis. Thyrotoxic crisis (TxC) Thyrotoxic crisis was confirmed in 6 patients (11% of the cohort). All affected patients were men. Their mean age was lower compared with patients without TxC (57.0 ± 5.4 vs. 62.9 ± 10.2 years), though the difference did not reach statistical significance (p = 0.085). The mean Burch–Wartofsky score (BWs) at AIT onset was 40 ± 11.7, increasing significantly during crisis to 85.8 ± 16.6 (range 65–110). Clinical presentation was uniform: all patients developed tachycardia (mean heart rate 127.5 ± 12.5/min), central nervous system symptoms, gastrointestinal/hepatic involvement, heart failure, and fever > 38°C. The results of TxC are summarized in Table 4 . Table 4 Diagnosis and management of thyrotoxic crisis (TxC) in patients with AIT Parameter #1 #2 #3 #4 #5 #6 All (n, %) / Mean ± SD CNS symptoms + + + + + + 6 (100) Hypertension + + + + + + 6 (100) Heart failure in history + – – + + – 3 (50) Congestive HF (NYHA) IV IV III IV IV III 6 (100) Tachycardia (max/min) 140–150 180–200 130–140 130–140 150–160 170–180 6 (100) CAD/MI – – – + – – 1 (17) ICD implantation + – – + – – 2 (33) GIT/hepatic symptoms + + + + + + 6 (100) Temperature (°C) 39.1 38.2 37.4 37.6 39.3 38.2 – Burch–Wartofsky score 95 90 70 65 110 85 85.8 ± 16.6 Corticosteroids + thionamides + + + + + + 6 (100) Max. daily dose of thyrostatics (mg/day) 800 PU 80 TM 90 TM 60 TM 600 PU 60 TM – Max. daily prednisone dose (mg/kg) 30 40 60 30 20 50 – Remission on conservative therapy – – – + – – 1 (17) Acute thyroidectomy + + + – + + 5 (83) Time from AIT to TxC (days) 43 70 59 50 57 107 64.3 ± 22.8 Duration of TxC (days) 4 8 4 8 18 3 7.5 ± 5.6 Time from AIT diagnosis to thyroidectomy (days) 47 78 63 – 75 110 74.6 ± 23.2 Abbreviations: A, amiodarone; AIT, amiodarone-induced thyrotoxicosis; TxC, thyrotoxic crisis; CAD, coronary artery disease; CNS, central nervous system; ECG, electrocardiogram; AF, atrial fibrillation; fT4, free thyroxine; GIT, gastrointestinal tract; ICD, implantable cardioverter-defibrillator; MI, myocardial infarction; HF, heart failure; NYHA, New York Heart Association; TG, thyroid gland; BP, blood pressure; TSH, thyroid-stimulating hormone; USG, ultrasonography; PU, propylthiouracil; TM, thiamazole; MT, methimazole The precipitating factor for thyrotoxic crisis is not always clearly identifiable. We consider that in two patients the trigger was administration of an iodine-based contrast agent during coronary angiography, in another patient sepsis combined with contrast administration for abdominal CT imaging (colonic abscess), another patient experienced a severe viral infection, and in one case the exact precipitating factor was not determined—most likely insufficient treatment of AIT and progression of cardiac failure. In the last patient, crisis was precipitated by worsening heart failure in the context of end-stage disease (the patient was listed for heart transplantation). Comparison of patients with and without TxC The main clinical, biochemical, and therapeutic differences between patients with and without TxC are summarized in Table 5 . Table 5 Characteristics of thyrotoxic crisis in patients with amiodarone-induced thyrotoxicosis (AIT) Parameter TxC (n = 6) No TxC (n = 49) p-value Significance Number of patients, n 6 49 – – Age (years ± SD) 57.0 ± 5.4 62.9 ± 10.2 0.085 ns Men, n (%) 6 (100.0) 39 (79.6) 0.281 ns Duration of therapy (days ± SD) 1000.2 ± 179.0 998.3 ± 529.6 0.986 ns Daily dose (mg) 171.0 ± 31.8 169.2 ± 29.2 0.890 ns Cumulative dose (g) 169.1 ± 35.4 170.1 ± 90.7 0.960 ns fT4 (pmol/L ± SD) 57.6 ± 18.5 41.4 ± 17.7 0.040 * Maximum fT4 (pmol/L ± SD) 74.5 ± 12.6 41.4 ± 17.7 0.0001 ** TSH (mIU/L ± SD) 0.006 ± 0.008 0.018 ± 0.060 0.154 ns Thyroid volume (mL) 20.0 ± 5.2 17.9 ± 9.0 0.581 ns Nodular goiter, n (%) 1 (16.7) 10 (20.4) 0.609 ns Diffuse goiter, n (%) 3 (50.0) 13 (26.5) 0.338 ns Hospitalization, n (%) 6 (100.0) 27 (55.1) 0.038 * Weight (kg) 86.3 ± 6.8 88.3 ± 14.2 0.106 ns Weight loss (kg) –8.2 ± 3.8 –5.8 ± 6.0 0.310 ns Systolic BP (mmHg) 132.5 ± 17.8 132.0 ± 13.9 0.929 ns Diastolic BP (mmHg) 78.3 ± 11.7 80.1 ± 9.3 0.677 ns Heart rate (beats/min) 127.5 ± 12.5 83.4 ± 16.7 < 0.0001 *** AF on ECG, n (%) 6 (100.0) 29 (59.2) 0.059 ns Corticosteroids + thionamides, n (%) 6 (100.0) 23 (46.9) 0.016 * Conservative therapy, n (%) 1 (16.7) 33 (67.3) 0.044 * Acute thyroidectomy, n (%) 5 (83.3) 4 (8.2) 0.0002 *** Elective thyroidectomy, n (%) 0 (0.0) 8 (16.3) 0.323 ns Abbreviations: A, amiodarone; AIT, amiodarone-induced thyrotoxicosis; TxC, thyrotoxic crisis; USG, ultrasonography; fT4, free thyroxine; TSH, thyroid-stimulating hormone; TG, thyroid gland; BP, blood pressure; AF, atrial fibrillation; ECG, electrocardiogram; SD, standard deviation. No differences were found in the duration of amiodarone use until AIT onset (1000.2 ± 179.0 vs. 998.3 ± 529.6 days; p = 0.986), daily dose (171.0 ± 31.8 vs. 169.2 ± 29.2 mg; p = 0.890), or cumulative dose (169.1 ± 35.4 vs. 170.1 ± 90.7 g; p = 0.960). Biochemically, TxC patients had significantly higher maximum fT4 values (74.5 ± 12.6 vs. 41.4 ± 17.6 pmol/L; p = 0.0001). Graf 3–5 show the dynamic changes in free thyroxine levels during follow-up of patients with amiodarone-induced thyrotoxicosis, with and without thyroid storm. Graf 4 and 5 demonstrate higher fT4 levels in patients with thyroid storm (n = 6) compared with those without thyroid storm (n = 49). Table 6 presents the frequency of laboratory monitoring of free thyroxine (fT4) in the patients studied. Laboratory assessments were significantly more frequent in patients with thyroid storm. Table 6 Longitudinal changes in thyroxine levels during clinical follow up in all patients with Amiodarone induced thyrotoxicosis. Dg of AIT FU 1 FU 2 FU 3 FU 4 FU 5 FU 6 last FU All patients whith Amiodarone induced Thyrotoxicosis (n = 55) days ± SD 0 34 ± 14 69 ± 23 117 ± 42 183 ± 73 279 ± 110 382 ± 146 724 ± 698 Average fT4 ± SD (mmol/L) 43.2 ± 18.3 36.6 ± 23.9 27.3 ± 18.2 17.6 ± 10.6 14.6 ± 10.2 14.5 ± 4.8 13.5 ± 4.0 13.4 ± 3.1 Median fT4 (mmlo/L) 39.3 26.9 21.0 13.7 12.8 14.4 13.8 13.5 TxC AIT patients whith Thyrotoxic Crisis (n = 6) days ± SD 0 21 ± 11 44 ± 13 74 ± 24 126 ± 52 244 ± 188 282 ± 225 705 ± 935 p-value: TxC vs No 0.02693 0.00294 0.00593 0.04386 0.00000 0.31795 0.94469 Significance - * ** ** * *** ns ns Average fT4 ± SD (mmol/L) 57.6 ± 18.5 57.4 ± 21.5 45.8 ± 22.6 34.0 ± 21.5 24.8 ± 27.9 16.9 ± 9.1 10.8 ± 3.9 12.9 ± 3.4 p-value: TxC vs No 0.03963 0.02427 0.00715 0.00000 0.00000 0.00000 0.31501 0.68308 Significance * * ** *** *** *** ns ns Median fT4 (mmlo/L) 59.0 55.0 42.5 35.0 11.4 13.7 10.8 13.9 No TxC AIT patients without TxC (n = 49) days ± SD 0 35 ± 14 72 ± 22 121 ± 39 189 ± 72 286 ± 90 397 ± 137 726 ± 675 Average fT4 ± SD (mmol/L) 41.4 ± 17.7 34.4 ± 23.2 25.0 ± 16.5 15.5 ± 6.2 13.3 ± 4.3 14.0 ± 3.4 14.0 ± 4.0 13.5 ± 3.1 Median fT4 (mmol/L) 38.1 25.7 20.0 13.3 12.8 14.5 13.9 13.7 Abbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; FU – follow up; TxC – Thyrotoxic crisis; SD – standard deviation Mean thyroid volume was comparable (20.0 ± 5.2 vs. 17.9 ± 9.0 mL; p = 0.581). Clinically, atrial fibrillation was more frequent in TxC patients (100% vs. 59%, p = 0.059). Mean heart rate was significantly higher (127.5 ± 12.5 vs. 83.4 ± 16.7/min; p < 0.0001). Hospitalization was required in all TxC patients (100% vs. 55%; p = 0.038). Regarding therapy, all TxC patients received combination treatment with corticosteroids and thionamides (100% vs. 47%; p = 0.016). The mean time from the onset of AIT to the development of TxC was 55.8 ± 10.1 days (median 57 days). The mean duration of thyrotoxic crisis until either acute thyroidectomy or remission was 8.4 ± 5.7 days (median 8 days). Urgent thyroidectomy was necessary in 83% of TxC patients compared with 8% in the non-TxC group (p = 0.0002). Elective thyroidectomy underwent 8 (18%) patients from non-TxC group. Discussion The number of studies specifically addressing amiodarone-induced thyrotoxic crisis (TxC) remains very limited. Most available evidence focuses either on patients with AIT or on TxC of other etiologies (20). Although progression of AIT to TxC is rare, it represents a serious clinical scenario described mainly in isolated case reports. Systematic analyses of epidemiological, demographic, clinical, and therapeutic aspects would require long-term patient enrollment and prospective registries, which likely explains the scarcity of robust data and reviews. Moreover, the majority of published studies are retrospective, often spanning many years, which contributes to heterogeneity in patient populations, diagnostic criteria, and treatment strategies. Our findings confirm the rarity of TxC in the context of AIT. Over a 20-year period, 55 patients with AIT were referred to our center, corresponding to an average of 2.8 ± 1.9 cases per year (median 3/year). TxC was diagnosed in 6 patients (11%), with a mean incidence of 0.3 ± 0.5 cases per year. Men constituted the majority of AIT patients overall (82%), and all TxC cases occurred in men. Angell et al. ( 2015 ) retrospectively analyzed 150 patients with thyrotoxicosis, of whom 25 developed TxC. The male-to-female ratio was 53:97 in the entire cohort and 9:16 in the TxC subgroup. Reported etiologies included 75 patients with Graves–Basedow disease, 2 with AIT, 1 with toxic adenoma, 1 with multinodular goiter, and 80 without a determined cause. Female predominance was explained by the underlying etiologies, particularly autoimmune thyroid disease (20). In contrast, Kaderli et al. ( 2016 ) retrospectively analyzed 11 patients with AIT who underwent total thyroidectomy, all of whom were men. Reported thyroid function parameters at diagnosis were TSH < 0.03 mIU/L and mean fT4 58.9 pmol/L (21). Our cohort showed similar findings, with mean TSH 0.006 ± 0.008 mIU/L and mean fT4 57.6 ± 18.5 pmol/L. In our TxC subgroup, 5 of 6 patients underwent urgent thyroidectomy. The mean interval from TxC onset to surgery was 7.6 ± 5.6 days during florid thyrotoxicosis and severe cardiac failure. Remission with conservative therapy was achieved in one patient. Similarly, Kaderli et al. reported 11 AIT patients treated with total thyroidectomy after preoperative carbimazole, corticosteroids, and beta-blockers; plasmapheresis was used in one case. Only one patient was euthyroid before surgery. No major intra- or postoperative complications were observed, and none of the patients developed TxC or died (21). Tomisti et al. ( 2012 ) retrospectively studied 24 patients with AIT and left ventricular systolic dysfunction treated between 1997 and 2010. The mean age was 61 years, and overall mortality risk was high. Total thyroidectomy resulted in rapid improvement of clinical status, recovery of systolic function, and reduced mortality (22). In our cohort, the mean age was 57 years, and we also observed that urgent thyroidectomy in patients with TxC and advanced heart failure was associated with improved outcomes. Remission of TxC and AIT led to gradual recovery of left ventricular systolic function (22). Capellani et al. (2020) retrospectively evaluated 207 AIT patients, including 51 who underwent thyroidectomy and 156 managed conservatively over a 20-year period. All causes and cardiac mortality at 5 and 10 years were significantly lower in the surgical group, particularly among patients with moderate-to-severe left ventricular dysfunction. In contrast, in those with preserved or only mildly reduced ejection fraction, mortality did not differ between surgical and medical management (23). More recent data support the role of early surgical intervention in selected high-risk patients with amiodarone-induced thyrotoxicosis. A contemporary cohort study by Frey et al. demonstrated that outcomes after total thyroidectomy are strongly influenced by baseline left ventricular systolic function, with the greatest benefit observed in patients with moderate-to-severe impairment of ejection fraction. These findings are consistent with our experience and suggest that, in patients with advanced cardiac disease, definitive surgical management may be advantageous when rapid control of thyrotoxicosis is required (24,25). Finally, a French multicenter retrospective study (2020) analyzed 270 patients with thyrotoxicosis admitted to 31 intensive care units, 92 of whom developed TxC. Amiodarone exposure was the leading cause (n = 30), followed by Graves–Basedow disease (n = 24), toxic adenoma or multinodular goiter (n = 38), autoimmune thyroiditis, and other etiologies. This large-scale analysis demonstrated that AIT constitutes a major risk factor for the development of TxC (25). Conclusion Despite ongoing research into new anti-arhythmic agents, amiodarone remains irreplaceable in clinical practice. Owing to its high iodine content, it predisposes susceptible individuals to thyroid dysfunction, with amiodarone-induced thyroid disorders among the most important complications of this otherwise highly effective drug. Amiodarone-induced thyrotoxic crisis (TxC) is an extremely rare condition associated with exceptionally high clinical risk and significant mortality. Early recognition and prompt, comprehensive therapeutic intervention are decisive for patient survival. Combination therapy with antithyroid agents and corticosteroids forms the basis of treatment, while in selected cases acute thyroidectomy remains the only viable life-saving option. Optimal management requires close multidisciplinary collaboration and strict coordination of care to stabilize vital functions and address the underlying endocrine and cardiac pathology. Patients with AIT are frequently burdened by advanced cardiac disease, which represents the key limiting factor for survival in the setting of TxC and restricts therapeutic options. Given the relatively small number of patients included in our cohort and the limited number of TxC cases, predictive factors cannot be confirmed with certainty. However, our findings suggest several potential clinical risk factors for the development of TxC in AIT: male sex, younger age, markedly elevated maximum fT4 values (> 74.5 pmol/L), thyroid volume > 19 mL, mixed type of AIT, acute decompensation of preexisting cardiac disease, and atrial fibrillation with rapid ventricular response. No association was observed with the duration of amiodarone therapy, nor with average daily or cumulative dose. Early recognition and treatment of AIT are therefore essential to prevent progression to TxC, which remains a major clinical challenge for internists and cardiologists. Once TxC develops, only immediate and comprehensive interdisciplinary management can significantly improve its otherwise poor prognosis. Regular monitoring of TSH, fT4, and fT3 in patients receiving amiodarone is therefore essential, as it enables the early detection of subclinical thyrotoxicosis and significantly influences disease severity and clinical outcomes. Declarations Author Contribution M.B. wrote the main text of the manuscript. M.B and A.B. conceived and designed the underlying scientific project.M.B and I.W. and Z.M. selected patients for inclusion and contributed with clinical management of patients. A.B. contributed with cardiology intensive care consultations and patients inclusion; performed the statistical analyses and preparate tables and graphs.N.P. contributed with scientific writing and analysis collected the scientific data.All authors reviewed the manuscript.All authors have read and agreed to the published version of the manuscript. Data Availability All data generated or analyzed during this study are included in this published article. References Florek JB, Lucas A, Girzadas D. Amiodarone. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Șorodoc V, Indrei L, Dobroghii C, Asaftei A, Ceasovschih A, Constantin M, et al. Amiodarone therapy: updated practical insights. J Clin Med. 2024;13(20):6094. Brophy JM, Nadeau L. Amiodarone vs dronedarone for atrial fibrillation: a retrospective cohort study. CJC Open. 2022;5(1):8–14. Khitri AR, Aliot EM, Capucci A, Connolly SJ, Crijns H, Hohnloser SH, et al. Celivarone for maintenance of sinus rhythm and conversion of atrial fibrillation/flutter. J Cardiovasc Electrophysiol. 2012;23(5):462–72. Dan GA, Martinez-Rubio A, Agewall S, et al. Antiarrhythmic drugs-clinical use and clinical decision making: a consensus document from the EHRA and ESC. Europace. 2018;20(5):738–45. Tomisti L, Rossi G, Bartalena L, Martino E, et al. The onset time of amiodarone-induced thyrotoxicosis depends on AIT type. Eur J Endocrinol. 2014;171:363–8. Bartalena L, Bogazzi F, Chiovato L, et al. European Thyroid Association guidelines for the management of amiodarone-associated thyroid dysfunction. Eur Thyroid J. 2018;7(2):55–66. Shifrin AL, et al. Endocrine emergencies. 1st ed. Philadelphia: Elsevier; 2022. Ylli D, Wartofsky L, Burman KD. Evaluation and treatment of amiodarone-induced thyroid disorders. J Clin Endocrinol Metab. 2021;106(1):226–36. Ross DS, Burch HB, Cooper DS, Greenlee MC, Laurberg P, Maia AL, et al. 2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis. Thyroid. 2016;26(10):1343–421. Jameson JL, De Groot LJ. Endocrinology: adult and pediatric. 7th ed. Philadelphia: Elsevier; 2016. Medic F, Bakula M, Alfirevic M, Bakula M, Mucic K, Maric N. Amiodarone and thyroid dysfunction. Acta Clin Croat. 2022;61(2):327–41. Hudzik B, Zubelewicz-Szkodzinska B. Amiodarone-related thyroid dysfunction. Intern Emerg Med. 2014;9(8):829–39. Tsang W, Houlden RL. Amiodarone-induced thyrotoxicosis: a review. Can J Cardiol. 2009;25(7):421–4. O’Sullivan AJ, Lewis M, Diamond T. Amiodarone-induced thyrotoxicosis: left ventricular dysfunction is associated with increased mortality. Eur J Endocrinol. 2006;154(4):533–6. Vinan-Vega M, Mantilla B, Jahan N, Peminda C, Nugent K, Lado-Abeal J, et al. Usefulness of plasmapheresis in patients with severe complicated thyrotoxicosis. Proc Bayl Univ Med Cent. 2020;34(2):279–82. Podoba J, Zajacová H. Amiodaron a poruchy funkcie štítnej žľazy. Cardiology. 2000;9:20–4. Maqdasy S, Benichou T, Dallel S, Roche B, Desbiez F, Montanier N, et al. Issues in amiodarone-induced thyrotoxicosis: update and review. Ann Endocrinol (Paris). 2019;80(1):54–60. Akamizu T, Satoh T, Isozaki O, et al. Diagnostic criteria, clinical features, and incidence of thyroid storm based on nationwide surveys. Thyroid. 2012;22(7):661–79. Angell TE, Lechner MG, Nguyen CT, et al. Clinical features and hospital outcomes in thyroid storm: a retrospective cohort study. J Clin Endocrinol Metab. 2015;100(2):451–9. Kaderli RM, Fahrner R, Christ ER, et al. Total thyroidectomy for amiodarone-induced thyrotoxicosis in the hyperthyroid state. Exp Clin Endocrinol Diabetes. 2016;124(1):45–8. Tomisti L, Materazzi G, Bartalena L, et al. Total thyroidectomy in patients with amiodarone-induced thyrotoxicosis and severe LV dysfunction. J Clin Endocrinol Metab. 2012;97(10):3515–21. Cappellani D, Papini P, Pingitore A, et al. Comparison between total thyroidectomy and medical therapy for amiodarone-induced thyrotoxicosis. J Clin Endocrinol Metab. 2020;105(1):41–9. Frey S, Kaderli RM, Christ ER, et al. Mortality after total thyroidectomy for amiodarone-induced thyrotoxicosis according to left ventricular ejection fraction. Eur J Endocrinol. 2023;188(6):789–798. Frey S, Kaderli RM, Staub JJ, et al. Amiodarone-induced thyrotoxicosis: is surgery underutilized in high-risk patients? Am J Cardiol. 2024;195:112–119. Bourcier S, Coutrot M, Kimmoun A, et al. Thyroid storm in the ICU: a retrospective multicenter study. Crit Care Med. 2020;48(1):83–90. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 02 Mar, 2026 Reviews received at journal 25 Feb, 2026 Reviewers agreed at journal 24 Feb, 2026 Reviewers agreed at journal 11 Feb, 2026 Reviewers invited by journal 10 Feb, 2026 Editor assigned by journal 09 Feb, 2026 Submission checks completed at journal 09 Feb, 2026 First submitted to journal 07 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-8816835\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":589861138,\"identity\":\"89dba13d-5d50-4213-9db0-0823766e5547\",\"order_by\":0,\"name\":\"Marianna Bystrianska\",\"email\":\"data:image/png;base64,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\",\"orcid\":\"\",\"institution\":\"University Hospital F.D. 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Roosevelt\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Iveta\",\"middleName\":\"\",\"lastName\":\"Wildova\",\"suffix\":\"\"},{\"id\":589861143,\"identity\":\"57cbffb4-6a92-4bde-95d4-789b1e13e832\",\"order_by\":3,\"name\":\"Zuzana Mesarošova\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University Hospital F.D. Roosevelt\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Zuzana\",\"middleName\":\"\",\"lastName\":\"Mesarošova\",\"suffix\":\"\"},{\"id\":589861145,\"identity\":\"ecd096b2-fcc9-405d-9869-39fa67c65328\",\"order_by\":4,\"name\":\"Nadezda Petejova\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"University of Ostrava\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Nadezda\",\"middleName\":\"\",\"lastName\":\"Petejova\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2026-02-07 16:23:13\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-8816835/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-8816835/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":102738537,\"identity\":\"97b071c8-5554-4b7b-8e06-2c6d72752dc5\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 06:59:45\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":67036,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eGraf 1. Correlation between max. fT4 and heart rate in AIT patients.\\u003c/p\\u003e\\n\\u003cp\\u003eCorrelation analysis (Spearman rₛ = 0.33; p = 0.014).\\u003c/p\\u003e\\n\\u003cp\\u003eAbbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; bpm – beat per minute\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/10197256edd6459984698dd9.png\"},{\"id\":102738539,\"identity\":\"26acac7c-6e4b-465f-8d97-73ade8efb5e8\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 06:59:45\",\"extension\":\"png\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":65668,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eGraf 2. Correlation between fT4 level and heart rate in AIT patients.\\u003c/p\\u003e\\n\\u003cp\\u003eCorrelation analysis (Spearman rₛ = 0.24; p = 0.076).\\u003c/p\\u003e\\n\\u003cp\\u003eAbbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; bpm – beat per minute\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage2.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/ccfb064da5ce7c67c4e341d0.png\"},{\"id\":102738541,\"identity\":\"5f0f8320-9400-4e74-9424-b3265a72a626\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 06:59:45\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":105449,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eGraf 3. Longitudinal changes in thyroxine levels during clinical follow up in all patients with Amiodarone induced thyrotoxicosis.\\u003c/p\\u003e\\n\\u003cp\\u003eAbbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; FU – follow up; TxC – Thyrotoxic crisis; SD – standard deviation\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage3.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/118c38ab38b83c4b3c87da33.png\"},{\"id\":102738540,\"identity\":\"571fc190-ac13-4679-9a78-aa38a0d975f0\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 06:59:45\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":107760,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eGraf 4. Longitudinal changes in thyroxine levels during clinical follow up in all patients with thyrotoxic crisis.\\u003c/p\\u003e\\n\\u003cp\\u003eAbbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; FU – follow up; TxC – Thyrotoxic crisis; SD – standard deviation\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/9b2d760c9fa97a32e57c6125.png\"},{\"id\":102749169,\"identity\":\"b1bc7da4-5131-42b3-ad47-2f659ccf09e3\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 09:12:09\",\"extension\":\"png\",\"order_by\":5,\"title\":\"Figure 5\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":97611,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eGraf 5. Longitudinal changes in thyroxine levels during clinical follow up in AIT patients without TxC.\\u003c/p\\u003e\\n\\u003cp\\u003eAbbreviations: AIT – amiodarone-induced thyrotoxicosis; fT4 – free thyroxine; FU – follow up; TxC – Thyrotoxic crisis; SD – standard deviation\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/22bddcc41c31af411b7cbe59.png\"},{\"id\":102751214,\"identity\":\"cb9c32e7-0176-44a1-ad13-b10215b454aa\",\"added_by\":\"auto\",\"created_at\":\"2026-02-16 09:24:21\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1609028,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8816835/v1/ee361b5c-bc46-40db-9651-4a943e39861f.pdf\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Amiodarone-Induced Thyrotoxicosis and Clinical Risk Factors for Thyrotoxic Crisis\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eAmiodarone remains one of the most effective antiarrhythmic agents, used across a wide range of supraventricular and ventricular arrhythmias. Although its clinical efficacy is well established, its use is limited by a considerable burden of extracardiac adverse effects. Despite extensive efforts to develop safer alternatives, no agent has demonstrated comparable efficacy in routine clinical practice. Expectations for new molecules, including amiodarone substitutes such as dronedarone, celivarone, or budiodarone, have not been fulfilled in clinical practice. Thus, in addition to sophisticated non-pharmacological treatments, amiodarone remains one of the most widely used antiarrhythmic drugs today (1).\\u003c/p\\u003e \\u003cp\\u003eThe pharmacological profile of amiodarone is characterized by multichannel blockade, resulting in prolongation of myocardial repolarization and refractoriness and accounting for its broad clinical use in the management of cardiac arrhythmias. However, its therapeutic efficacy is offset by a substantial risk of extracardiac adverse effects, including pulmonary toxicity, hepatotoxicity, and thyroid dysfunction (2). Althought new molecules like dronedarone, celivarone, and budiodarone have been developed to minimize these adverse effects, clinical studies have not demonstrated their significant advantage over amiodarone. Dronedarone, for instance, was initially developed as a less toxic alternative to amiodarone, but its efficacy in treating atrial fibrillation was lower, and its use is limited due to the risk of hepatotoxicity (3). Celivarone, although promising in preclinical studies, has not shown sufficient efficacy in clinical trials (4).\\u003c/p\\u003e \\u003cp\\u003eDespite major advances in catheter ablation and implantable cardioverter-defibrillator therapy, amiodarone remains indispensable in contemporary arrhythmia management.\\u003c/p\\u003e\\n\\u003ch3\\u003eAmiodarone-Induced Thyrotoxicosis\\u003c/h3\\u003e\\n\\u003cp\\u003eAmiodarone-induced thyrotoxicosis (AIT) is one of the most feared complications of therapy. It may occur early during treatment, after long-term use, or even following drug discontinuation due to the drug\\u0026rsquo;s high lipophilicity and prolonged biological half-life. According to published data, the incidence of thyrotoxicosis peaks between the second and third year of treatment (5,6). Trip et al. reported AIT in 2.5% of patients after 18 months and in up to 33.5% after 48 months of therapy. The occurrence of AIT appears independent of both the daily and cumulative dose of amiodarone, with a male predominance of approximately 3:1 (6).\\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003eType I AIT\\u003c/b\\u003e most commonly arises in the setting of preexisting thyroid disease. Thyrotoxicosis is predominantly triggered by an iodine-induced mechanism and typically occurs in latent Graves\\u0026rsquo; disease or nodular goiter. Patients usually present with nodular or diffuse goiter (\\u0026gt;\\u0026thinsp;15 g) or positive TSH-receptor antibodies. Ultrasound (USG) typically demonstrates structural changes of the thyroid gland with normal or increased vascularity (flow grade I\\u0026ndash;III) (7,8). Twenty-four-hour radioactive iodine uptake (RAIU) is normal or greater than 8% (1,7,8).\\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003eType II AIT\\u003c/b\\u003e occurs in patients without previous structural or functional thyroid disease. USG typically reveals a normal thyroid gland or a small diffuse goiter (\\u0026le;\\u0026thinsp;15 g), TSH-receptor antibodies are negative, vascularity is absent (flow grade 0), and RAIU is markedly reduced or absent. The underlying mechanism reflects a cytotoxic effect of amiodarone on thyrocytes with sterile inflammatory changes; interleukin-6 (IL-6) may be elevated (4,9).\\u003c/p\\u003e \\u003cp\\u003e \\u003cb\\u003eMixed AIT\\u003c/b\\u003e is diagnosed when patients exhibit features of both Type I (e.g., nodular or large diffuse goiter, or positive TSH-receptor antibodies) and Type II (reduced vascularity on USG and low RAIU) (8\\u0026ndash;10).\\u003c/p\\u003e \\u003cdiv id=\\\"Sec3\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eClinical Manifestation of AIT\\u003c/h2\\u003e \\u003cp\\u003eAIT presents across a spectrum from oligosymptomatic disease to overt thyrotoxicosis; rarely, it progresses to life-threatening thyrotoxic crisis (TxC). In polymorbid cardiac patients receiving beta-blockers or other rate-controlling therapies, classical hyperthyroid signs may be blunted. However, when these patients limited adaptive mechanisms are overwhelmed, AIT can significantly increase their risk of morbidity and mortality. Because of amiodarone\\u0026rsquo;s pharmacokinetics, AIT may develop at any time during therapy or several months after withdrawal. (6,7).\\u003c/p\\u003e \\u003c/div\\u003e\\n\\u003ch3\\u003eTreatment of AIT\\u003c/h3\\u003e\\n\\u003cp\\u003eThe treatment of AIT is complex and based on the clinical condition of the patient. Spontaneous remission of the disease is rare and occurs only in cases of mild AIT type II.\\u003c/p\\u003e \\u003cp\\u003eIn accordance with current European Thyroid Association (ETA) recommendations, the primary focus is on early differentiation of the patient's AIT type, which creates a prerequisite for adequate therapy (7,8).\\u003c/p\\u003e \\u003cp\\u003eContinuation vs discontinuation of amiodarone remains debated. Once AIT is diagnosed, it is logical to discontinue amiodarone therapy because it is directly involved in the pathogenesis of the disease. However, in certain cases, discontinuation of amiodarone treatment represents a complex and serious decision that should be preceded by an interdisciplinary consortium with an individualized risk-benefit assessment. These are mainly cases with severe ventricular, life-threatening tachycardias and multimorbid patients with severe heart failure and high cardiovascular risk (11,12,13). The specific therapeutic management of a patient depends on the type of AIT.\\u003c/p\\u003e\\n\\u003ch3\\u003eTreatment of AIT Type I\\u003c/h3\\u003e\\n\\u003cp\\u003eType I AIT is characterized by increased thyroid hormone synthesis, making thionamides the treatment of choice. Higher initial doses are recommended compared with other causes of thyrotoxicosis, such as Graves\\u0026rsquo; disease (7,8,13). Suggested regimens include: thiamazole 30\\u0026ndash;40 mg/day, methimazole 40\\u0026ndash;60 mg/day, or propylthiouracil 300\\u0026ndash;600 mg/day. Dosage and duration should be guided by the clinical course, decline in thyroid hormone levels, and achievement of remission (7,13).\\u003c/p\\u003e \\u003cp\\u003ePotassium perchlorate (250 mg four times daily) may be added. This drug has been used since the 1950s and competitively inhibits iodine uptake, thereby promoting intrathyroidal iodine clearance. Its use is limited by potential toxicity, including agranulocytosis and aplastic anemia, which may be fatal. The maximum daily dose should not exceed 1 g, and treatment duration should be limited to 30 days (14,15). Clinical remission occurs earlier with combined thionamide\\u0026ndash;perchlorate therapy than with thionamides alone.\\u003c/p\\u003e \\u003cp\\u003eMost patients improve within 2\\u0026ndash;3 months. Average treatment duration is 6\\u0026ndash;18 months, after which thyrostatics may be tapered (13). If no improvement is observed within 4\\u0026ndash;6 weeks, glucocorticoids should be added and the diagnosis reconsidered, particularly with regard to mixed AIT (8).\\u003c/p\\u003e\\n\\u003ch3\\u003eTreatment of AIT Type II\\u003c/h3\\u003e\\n\\u003cp\\u003eType II AIT may present with mild symptoms and occasionally undergo spontaneous remission, though it carries a risk of cardiac deterioration. Its pathophysiology is consistent with destructive thyroiditis; therefore, glucocorticoids are the treatment of choice. Prednisone is recommended at 0.5\\u0026ndash;0.7 mg/kg/day (average 30\\u0026ndash;40 mg/day). High doses are typically administered for 4\\u0026ndash;6 weeks, followed by gradual tapering. With early initiation, the therapeutic response is usually rapid and favorable. Treatment should continue until complete remission, with a mean duration of 2\\u0026ndash;3 months. Thionamides are not considered first-line therapy for Type II AIT (7,8).\\u003c/p\\u003e\\n\\u003ch3\\u003eTreatment of Mixed AIT\\u003c/h3\\u003e\\n\\u003cp\\u003eIn cases of mixed AIT, or when the subtype cannot be clearly defined, combination therapy is recommended. This includes thionamides (40\\u0026ndash;60 mg/day) and prednisone (40\\u0026ndash;50 mg/day). Most mixed cases resemble Type II AIT; therefore, corticosteroid administration is essential (7,8). In patients with severe heart failure where rapid remission is required, combined therapy should be initiated regardless of subtype (9,10).\\u003c/p\\u003e \\u003cdiv id=\\\"Sec8\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eAdditional Therapies\\u003c/h2\\u003e \\u003cp\\u003eBeta-blockers are indicated in all types of AIT, with nonselective agents preferred due to their additional inhibition of peripheral thyroxine-to-triiodothyronine conversion. Lithium may also inhibit thyroid hormone production and release, but its use is limited by adverse effects such as diabetes insipidus and arrhythmias (8,9).\\u003c/p\\u003e \\u003cp\\u003ePlasmapheresis can transiently reduce circulating thyroid hormone levels, but its clinical benefit remains controversial. It should be considered only when medical therapy fails and urgent thyroidectomy is planned (7,16).\\u003c/p\\u003e \\u003cp\\u003eTotal thyroidectomy is indicated in when medical therapy is ineffective, when there is a marked reduction in left ventricular ejection fraction associate with cardiac decompensation, when amiodarone reintroduction is required, or in patients with a large goiter causing airway compression (17,18). The procedure results in rapid achievement of euthyroidism, significantly improving prognosis and cardiac status. Surgery may be elective, urgent, or emergency, particularly in the context of thyrotoxic crisis. According to the 2018 European Thyroid Association guidelines, indications for elective thyroidectomy in AIT include:\\u003c/p\\u003e \\u003cp\\u003ea) definitive treatment of thyrotoxicosis,\\u003c/p\\u003e \\u003cp\\u003eb) continuation of amiodarone therapy in patients with severe arrhythmias,\\u003c/p\\u003e \\u003cp\\u003ec) c) adverse effects of AIT therapy (7).\\u003c/p\\u003e \\u003cp\\u003eUrgent thyroidectomy should be considered in:\\u003c/p\\u003e \\u003cp\\u003e\\u0026bull; progressive heart failure despite optimal medical therapy, especially with severe systolic dysfunction (mortality risk 30\\u0026ndash;50%),\\u003c/p\\u003e \\u003cp\\u003e\\u0026bull; unstable arrhythmias refractory to medication,\\u003c/p\\u003e \\u003cp\\u003e\\u0026bull; inadequate response to comprehensive medical management.\\u003c/p\\u003e \\u003cp\\u003eThese cases require careful risk\\u0026ndash;benefit assessment by a multidisciplinary team, including endocrinologists, cardiologists, anesthesiologists, and surgeons (7,8,19).\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Methodology and Patient Cohort Characteristics\",\"content\":\"\\u003cp\\u003e For this study, we adhered to the Declaration of Helsinki, 2013, Good Clinical Practice, and obtained approval from the institutional Ethics Review Board of University Hospital F.D. Roosevelt Banska Bystrica (Reference number 17/2024) Slovak Republic. Written informed consent was obtained from all patients involved in the study.\\u003c/p\\u003e \\u003cp\\u003eThe retrospective study cohort consisted of 55 patients with amiodarone-induced thyrotoxicosis (AIT) who were followed up between 2005 and 2024. All consecutive patients with confirmed AIT were included. Patients with other forms of hyperthyroidism or thyrotoxicosis of different etiology were excluded.\\u003c/p\\u003e \\u003cp\\u003eAll patients were diagnosed and treated at the Endocrinology Outpatient Department of the University Hospital F.D. Roosevelt, Banska Bystrica. If the severity of their condition required hospitalization, they were admitted to the II. Department of Internal Medicine, University Hospital F.D. Roosevelt, or to the Department of Cardiology, Slovak Health University, Middle-Slovakian Institute of Heart and Vascular Diseases, Banska Bystrica. After stabilization, patients were followed up in the Endocrinology Outpatient Clinic. Clinical history data were obtained directly from patients and supplemented by hospital records.\\u003c/p\\u003e \\u003cp\\u003eEach patient underwent initial clinical evaluation, standard laboratory testing, and thyroid USG. Additional diagnostic procedures and specialist consultations were performed as indicated. The differential diagnosis of AIT type was made according to standard diagnostic criteria. The following parameters were evaluated: pre-existing thyroid disease, thyroid autoantibody status, USG morphology and vascularity, presence of nodules. medications administered, and therapeutic response. Thyroid volume was measured by USG using the ellipsoid model.\\u003c/p\\u003e \\u003cp\\u003eVenous blood samples were collected into serum separation tubes containing a gel separator (4.9 mL). Serum levels of TSH, fT4, anti-TPO, and anti-Tg were determined by chemiluminescent immunoassay (ECLIA) using the DxI 9000 system (Beckman Coulter), while anti-TSH receptor antibodies (TRAb) were measured on the Cobas e 411 analyzer (Roche Diagnostics).\\u003c/p\\u003e \\u003cp\\u003eReference laboratory ranges were as follows: free thyroxine (fT4), 7.8\\u0026ndash;14.4 pmol/L; thyroid-stimulating hormone (TSH), 0.35\\u0026ndash;5.33 mU/L. Remission of AIT was defined as normalization of fT4 values within the reference range. The frequency of clinical and laboratory follow-ups was individualized according to disease severity. For long-term assessment, patient status was evaluated at the most recent outpatient visit.\\u003c/p\\u003e \\u003cdiv id=\\\"Sec10\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStatistical Analysis\\u003c/h2\\u003e \\u003cp\\u003eDescriptive statistics were used for quantitative parameters. Normality of distribution was tested using the Shapiro\\u0026ndash;Wilk test. Homogeneity of variance was assessed with Fisher\\u0026rsquo;s two-tailed test. Depending on distribution, comparisons between groups were performed with either the unpaired t-test or the nonparametric Mann\\u0026ndash;Whitney U test. Categorical variables were analyzed using Pearson\\u0026rsquo;s χ\\u0026sup2; test. The correlation analysis was performed using Spearman\\u0026rsquo;s rank correlation test. Statistical significance was defined as p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05.\\u003c/p\\u003e \\u003cp\\u003eResults are presented as absolute numbers and percentages for categorical variables, and as mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;standard deviation for continuous variables. Statistical analyses were performed using GraphPad Prism 10.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eThe study cohort included 55 patients diagnosed with AIT between 2005 and 2024. The majority were men (n\\u0026thinsp;=\\u0026thinsp;45; 82%), while 10 patients were women (18%). The mean age at diagnosis was 62.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.9 years. Male patients were significantly younger than female patients (60.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;6.5 vs. 69.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.3 years, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05). The mean follow-up duration was 2.8 years. The mean time to remission with conservative therapy in 46 patients was 106.7\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;62.1 days, while 9 patients who underwent acute total thyroidectomy reached remission after 72.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.3 days.\\u003c/p\\u003e \\u003cdiv id=\\\"Sec12\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eComorbidities and indications for amiodarone\\u003c/h2\\u003e \\u003cp\\u003eArterial hypertension was present in all patients (100%). Coronary artery disease was diagnosed in 42% (n\\u0026thinsp;=\\u0026thinsp;23), of whom 18% (n\\u0026thinsp;=\\u0026thinsp;10) had a history of myocardial infarction. A total of 64% (n\\u0026thinsp;=\\u0026thinsp;35) had heart failure, and 20% (n\\u0026thinsp;=\\u0026thinsp;11) had an implanted cardioverter-defibrillator (ICD). Diabetes mellitus was present in 18% (n\\u0026thinsp;=\\u0026thinsp;10).\\u003c/p\\u003e \\u003cp\\u003eThe main indication for amiodarone therapy was atrial fibrillation (n\\u0026thinsp;=\\u0026thinsp;43; 78%). Other indications included ventricular tachyarrhythmias (n\\u0026thinsp;=\\u0026thinsp;7; 13%) and frequent ventricular extrasystoles (n\\u0026thinsp;=\\u0026thinsp;5; 9%). Table.1\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec13\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eLaboratory and thyroid findings\\u003c/h2\\u003e \\u003cp\\u003eAt the time of AIT diagnosis, the mean daily dose of amiodarone was 169.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;29.2 mg, and the mean cumulative dose was 170.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;86.1 g. The average duration of amiodarone therapy before AIT onset was 988.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;502 days.\\u003c/p\\u003e \\u003cp\\u003eLaboratory evaluation at the time of AIT diagnosis showed a mean serum TSH of 0.017\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.052 mIU/L and a mean fT4 of 43.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.3 pmol/L (median 39.3 pmol/L; range: 15.6\\u0026ndash;90.0 pmol/L). In patients who developed thyrotoxic crisis (TxC), the maximum fT4 concentration reached 74.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.6 pmol/L (median 73.7 pmol/L; range 60.5\\u0026ndash;91.0 pmol/L). The maximum fT4 values in the entire cohort of patients with AIT were 49.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;24.0 pmol/L (median 45.0 pmol/L; range 16.6\\u0026ndash;124.6 pmol/L). The fT4 concentration alone did not predict the severity of the disease or the development of thyrotoxic crisis. Ultrasonographic evaluation revealed a mean thyroid volume of 18.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.7 mL. Goiter was present in 47% of patients (n\\u0026thinsp;=\\u0026thinsp;26), more frequently in women (80%) than in men (40%) (p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05). More detailed characteristics of patients with AIT presented in Table.2.\\u003c/p\\u003e \\u003cp\\u003eIn the comparison between male and female patients, a statistically significant difference was observed in the prevalence of goiter, which was present in 8 women (80%) compared with 18 men (40%). Statistically significant differences were also found in body weight and in systolic blood pressure. A weak but statistically significant positive correlation was identified between maximum fT4 levels and heart rate (Spearman\\u0026rsquo;s correlation coefficient rₛ = 0.33, p\\u0026thinsp;=\\u0026thinsp;0.014) (graf 1) and non-significant correlation between fT4 levels and heart rate (Spearman\\u0026rsquo;s correlation coefficient rₛ = 0.24, p\\u0026thinsp;=\\u0026thinsp;0.076) (graf 2).\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec14\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eTypes of AIT\\u003c/h2\\u003e \\u003cp\\u003eBased on established diagnostic criteria, patients were classified into three subtypes according to TSH receptor antibody positivity, as well as structural, vascular, and volumetric characteristics of the thyroid gland. Type I AIT was identified in 13 patients (23%), Type II AIT in 24 patients (44%), and mixed AIT in 18 patients (33%).\\u003c/p\\u003e \\u003cp\\u003eWomen were more frequently diagnosed with Type I AIT (50% of women vs. 18% of men), while Type II was more common among men (47% vs. 30%). Mixed forms were present in both sexes but predominated in men (35% vs. 20%). Table\\u0026nbsp;\\u003cspan refid=\\\"Tab3\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab1\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 1\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eBasic characteristics of patients with amiodarone-induced thyrotoxicosis (AIT).\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"2\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eParameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eValue\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNumber of patients, n\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e55\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAge, years (mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e62.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMen, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e45 (82%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eWomen, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e10 (18%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAge \\u0026ndash; men (years)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e60.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;6.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAge \\u0026ndash; women (years)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e69.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eComorbidities\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHypertension, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e55 (100%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDiabetes mellitus, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e10 (18%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCoronary artery disease, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e23 (42%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003ePrior myocardial infarction, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e10 (18%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHeart failure, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e35 (64%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eICD implanted, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11 (20%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eIndications for amiodarone\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAtrial fibrillation, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e43 (78%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eVentricular tachyarrhythmias, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e7 (13%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eFrequent ventricular extrasystoles, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5 (9%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"2\\\"\\u003eAbbreviations: AIT \\u0026ndash; amiodarone-induced thyrotoxicosis; ICD \\u0026ndash; implantable cardioverter-defibrillator.\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab2\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 2\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eClinical, laboratory, and ultrasonographic characteristics at AIT diagnosis by sex.\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"5\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eParameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eMen (n\\u0026thinsp;=\\u0026thinsp;45)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eWomen (n\\u0026thinsp;=\\u0026thinsp;10)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003ep\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eAll (n\\u0026thinsp;=\\u0026thinsp;55)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDuration until AIT (days)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e945.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;359.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1234\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;896.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.340\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e988.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;502.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003efT4 at diagnosis (pmol/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e43.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e42.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;16.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.856\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e43.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTSH at diagnosis (mIU/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.016\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.055\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.021\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.042\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.802\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.017\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.052\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eThyroid volume (mL)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e18.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e17.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;7.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.932\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e18.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eGoiter, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e18 (40%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e8 (80%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.025\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e26 (47%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHospitalized, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e26 (58%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e7 (70%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.476\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e33 (60%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eWeight (kg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e90.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e78.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.011\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e88.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSystolic BP (mmHg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e130.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e139.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.059\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e132.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDiastolic BP (mmHg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e79.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e81.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.575\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e80.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHeart rate (/min)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e88.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;22.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e85.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;10.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.649\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e87.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;21.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAF on ECG, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e28 (62%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e7 (70%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.463\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e35 (64%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"5\\\"\\u003eAbbreviations: AIT \\u0026ndash; amiodarone-induced thyrotoxicosis; USG \\u0026ndash; ultrasonography; fT4 \\u0026ndash; free thyroxine; TSH \\u0026ndash; thyroid-stimulating hormone; BP \\u0026ndash; blood pressure; AF \\u0026ndash; atrial fibrillation; ECG \\u0026ndash; electrocardiogram.\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab3\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 3\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eDistribution of AIT types\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"4\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAIT type\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eMen (n\\u0026thinsp;=\\u0026thinsp;45)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eWomen (n\\u0026thinsp;=\\u0026thinsp;10)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eAll (n\\u0026thinsp;=\\u0026thinsp;55)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eType I, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e8 (18%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5 (50%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e13 (23%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eType II, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e21 (47%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e3 (30%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e24 (44%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMixed type, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e16 (35%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2 (20%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e18 (33%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"4\\\"\\u003eAbbreviations: AIT \\u0026ndash; amiodarone-induced thyrotoxicosis.\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec15\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eThyrotoxic crisis (TxC)\\u003c/h2\\u003e \\u003cp\\u003eThyrotoxic crisis was confirmed in 6 patients (11% of the cohort). All affected patients were men. Their mean age was lower compared with patients without TxC (57.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.4 vs. 62.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;10.2 years), though the difference did not reach statistical significance (p\\u0026thinsp;=\\u0026thinsp;0.085).\\u003c/p\\u003e \\u003cp\\u003eThe mean Burch\\u0026ndash;Wartofsky score (BWs) at AIT onset was 40\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;11.7, increasing significantly during crisis to 85.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;16.6 (range 65\\u0026ndash;110). Clinical presentation was uniform: all patients developed tachycardia (mean heart rate 127.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.5/min), central nervous system symptoms, gastrointestinal/hepatic involvement, heart failure, and fever\\u0026thinsp;\\u0026gt;\\u0026thinsp;38\\u0026deg;C. The results of TxC are summarized in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab4\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab4\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 4\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eDiagnosis and management of thyrotoxic crisis (TxC) in patients with AIT\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eParameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e#1\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e#2\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e#3\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e#4\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e#5\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e#6\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003eAll (n, %) / Mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCNS symptoms\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHypertension\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHeart failure in history\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e3 (50)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCongestive HF (NYHA)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eIV\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eIV\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eIII\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eIV\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eIV\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eIII\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTachycardia (max/min)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e140\\u0026ndash;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e180\\u0026ndash;200\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e130\\u0026ndash;140\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e130\\u0026ndash;140\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e150\\u0026ndash;160\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e170\\u0026ndash;180\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCAD/MI\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1 (17)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eICD implantation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2 (33)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eGIT/hepatic symptoms\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTemperature (\\u0026deg;C)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e39.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e38.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e37.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e37.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e39.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e38.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eBurch\\u0026ndash;Wartofsky score\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e95\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e90\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e70\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e65\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e110\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e85\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e85.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;16.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCorticosteroids\\u0026thinsp;+\\u0026thinsp;thionamides\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e6 (100)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMax. daily dose of thyrostatics (mg/day)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e800 PU\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e80 TM\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e90 TM\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e60 TM\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e600 PU\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e60 TM\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMax. daily prednisone dose (mg/kg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e30\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e40\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e60\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e30\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e20\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e50\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eRemission on conservative therapy\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1 (17)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAcute thyroidectomy\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e+\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e5 (83)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTime from AIT to TxC (days)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e43\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e70\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e59\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e50\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e57\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e107\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e64.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;22.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDuration of TxC (days)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e18\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e7.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTime from AIT diagnosis to thyroidectomy (days)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e47\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e78\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e63\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e75\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e110\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e74.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;23.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"8\\\"\\u003eAbbreviations: A, amiodarone; AIT, amiodarone-induced thyrotoxicosis; TxC, thyrotoxic crisis; CAD, coronary artery disease; CNS, central nervous system; ECG, electrocardiogram; AF, atrial fibrillation; fT4, free thyroxine; GIT, gastrointestinal tract; ICD, implantable cardioverter-defibrillator; MI, myocardial infarction; HF, heart failure; NYHA, New York Heart Association; TG, thyroid gland; BP, blood pressure; TSH, thyroid-stimulating hormone; USG, ultrasonography; PU, propylthiouracil; TM, thiamazole; MT, methimazole\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eThe precipitating factor for thyrotoxic crisis is not always clearly identifiable. We consider that in two patients the trigger was administration of an iodine-based contrast agent during coronary angiography, in another patient sepsis combined with contrast administration for abdominal CT imaging (colonic abscess), another patient experienced a severe viral infection, and in one case the exact precipitating factor was not determined\\u0026mdash;most likely insufficient treatment of AIT and progression of cardiac failure. In the last patient, crisis was precipitated by worsening heart failure in the context of end-stage disease (the patient was listed for heart transplantation).\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec16\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eComparison of patients with and without TxC\\u003c/h2\\u003e \\u003cp\\u003eThe main clinical, biochemical, and therapeutic differences between patients with and without TxC are summarized in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab5\\\" class=\\\"InternalRef\\\"\\u003e5\\u003c/span\\u003e.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab5\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 5\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eCharacteristics of thyrotoxic crisis in patients with amiodarone-induced thyrotoxicosis (AIT)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"5\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eParameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eTxC (n\\u0026thinsp;=\\u0026thinsp;6)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eNo TxC (n\\u0026thinsp;=\\u0026thinsp;49)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003ep-value\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eSignificance\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNumber of patients, n\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e49\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u0026ndash;\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAge (years\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e57.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e62.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;10.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.085\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMen, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6 (100.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e39 (79.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.281\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDuration of therapy (days\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1000.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;179.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e998.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;529.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.986\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDaily dose (mg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e171.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;31.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e169.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;29.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.890\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCumulative dose (g)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e169.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;35.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e170.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;90.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.960\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003efT4 (pmol/L\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e57.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e41.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;17.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.040\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMaximum fT4 (pmol/L\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e74.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e41.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;17.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.0001\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e**\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTSH (mIU/L\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.006\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.008\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.018\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.060\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.154\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eThyroid volume (mL)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e20.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e17.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.581\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNodular goiter, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1 (16.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e10 (20.4)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.609\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDiffuse goiter, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e3 (50.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e13 (26.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.338\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHospitalization, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6 (100.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e27 (55.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.038\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eWeight (kg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e86.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;6.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e88.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;14.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.106\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eWeight loss (kg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u0026ndash;8.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;3.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u0026ndash;5.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;6.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.310\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSystolic BP (mmHg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e132.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;17.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e132.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.929\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDiastolic BP (mmHg)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e78.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;11.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e80.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.677\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHeart rate (beats/min)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e127.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e83.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;16.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u0026lt;\\u0026thinsp;0.0001\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAF on ECG, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6 (100.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e29 (59.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.059\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCorticosteroids\\u0026thinsp;+\\u0026thinsp;thionamides, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6 (100.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e23 (46.9)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.016\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eConservative therapy, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1 (16.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e33 (67.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.044\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAcute thyroidectomy, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5 (83.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e4 (8.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.0002\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eElective thyroidectomy, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0 (0.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e8 (16.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.323\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"5\\\"\\u003eAbbreviations: A, amiodarone; AIT, amiodarone-induced thyrotoxicosis; TxC, thyrotoxic crisis; USG, ultrasonography; fT4, free thyroxine; TSH, thyroid-stimulating hormone; TG, thyroid gland; BP, blood pressure; AF, atrial fibrillation; ECG, electrocardiogram; SD, standard deviation.\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eNo differences were found in the duration of amiodarone use until AIT onset (1000.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;179.0 vs. 998.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;529.6 days; p\\u0026thinsp;=\\u0026thinsp;0.986), daily dose (171.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;31.8 vs. 169.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;29.2 mg; p\\u0026thinsp;=\\u0026thinsp;0.890), or cumulative dose (169.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;35.4 vs. 170.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;90.7 g; p\\u0026thinsp;=\\u0026thinsp;0.960).\\u003c/p\\u003e \\u003cp\\u003eBiochemically, TxC patients had significantly higher maximum fT4 values (74.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.6 vs. 41.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;17.6 pmol/L; p\\u0026thinsp;=\\u0026thinsp;0.0001).\\u003c/p\\u003e \\u003cp\\u003eGraf 3\\u0026ndash;5 show the dynamic changes in free thyroxine levels during follow-up of patients with amiodarone-induced thyrotoxicosis, with and without thyroid storm. Graf 4 and 5 demonstrate higher fT4 levels in patients with thyroid storm (n\\u0026thinsp;=\\u0026thinsp;6) compared with those without thyroid storm (n\\u0026thinsp;=\\u0026thinsp;49).\\u003c/p\\u003e \\u003cp\\u003eTable\\u0026nbsp;\\u003cspan refid=\\\"Tab6\\\" class=\\\"InternalRef\\\"\\u003e6\\u003c/span\\u003e presents the frequency of laboratory monitoring of free thyroxine (fT4) in the patients studied. Laboratory assessments were significantly more frequent in patients with thyroid storm.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab6\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 6\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eLongitudinal changes in thyroxine levels during clinical follow up in all patients with Amiodarone induced thyrotoxicosis.\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"9\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c9\\\" colnum=\\\"9\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eDg of AIT\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eFU 1\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eFU 2\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eFU 3\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eFU 4\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eFU 5\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003eFU 6\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003elast FU\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"8\\\" nameend=\\\"c9\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003eAll patients whith Amiodarone induced Thyrotoxicosis (n\\u0026thinsp;=\\u0026thinsp;55)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003edays\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e34\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;14\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e69\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;23\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e117\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;42\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e183\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;73\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e279\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;110\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e382\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;146\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e724\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;698\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAverage fT4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/b\\u003e (mmol/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e43.2\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;18.3\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e36.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;23.9\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e27.3\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;18.2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e17.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;10.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e14.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;10.2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e14.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;4.8\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e13.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;4.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e13.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;3.1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMedian fT4 (mmlo/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e39.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e26.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e21.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e13.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e12.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e14.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e13.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e13.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eTxC\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"8\\\" nameend=\\\"c9\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAIT patients whith Thyrotoxic Crisis (n\\u0026thinsp;=\\u0026thinsp;6)\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003edays\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e21\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;11\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e44\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e74\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;24\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e126\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;52\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e244\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;188\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e282\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;225\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e705\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;935\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003ep-value: TxC vs No\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.02693\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.00294\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.00593\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e0.04386\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e0.00000\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.31795\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e0.94469\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSignificance\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e-\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e**\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e**\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAverage fT4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/b\\u003e (mmol/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e57.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;18.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e57.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;21.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e45.8\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;22.6\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e34.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;21.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e24.8\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;27.9\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e16.9\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;9.1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e10.8\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;3.9\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e12.9\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;3.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003ep-value: TxC vs No\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.03963\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.02427\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.00715\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.00000\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e0.00000\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e0.00000\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.31501\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e0.68308\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSignificance\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e*\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e**\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e***\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003ens\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMedian fT4 (mmlo/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e59.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e55.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e42.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e35.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e11.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e13.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e10.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e13.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eNo TxC\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"8\\\" nameend=\\\"c9\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAIT patients without TxC (n\\u0026thinsp;=\\u0026thinsp;49)\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003edays\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e35\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;14\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e72\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;22\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e121\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;39\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e189\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;72\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e286\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;90\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e397\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;137\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e726\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;675\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAverage fT4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/b\\u003e (mmol/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e41.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;17.7\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e34.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;23.2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e25.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;16.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e15.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;6.2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e13.3\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;4.3\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e14.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;3.4\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e14.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;4.0\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e13.5\\u003c/b\\u003e\\u003c/p\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026plusmn;\\u0026thinsp;3.1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMedian fT4 (mmol/L)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e38.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e25.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e20.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e13.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e12.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e14.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e13.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e13.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003ctfoot\\u003e \\u003ctr\\u003e\\u003ctd colspan=\\\"9\\\"\\u003eAbbreviations: AIT \\u0026ndash; amiodarone-induced thyrotoxicosis; fT4 \\u0026ndash; free thyroxine; FU \\u0026ndash; follow up; TxC \\u0026ndash; Thyrotoxic crisis; SD \\u0026ndash; standard deviation\\u003c/td\\u003e\\u003c/tr\\u003e \\u003c/tfoot\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eMean thyroid volume was comparable (20.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.2 vs. 17.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.0 mL; p\\u0026thinsp;=\\u0026thinsp;0.581).\\u003c/p\\u003e \\u003cp\\u003eClinically, atrial fibrillation was more frequent in TxC patients (100% vs. 59%, p\\u0026thinsp;=\\u0026thinsp;0.059). Mean heart rate was significantly higher (127.5\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.5 vs. 83.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;16.7/min; p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.0001). Hospitalization was required in all TxC patients (100% vs. 55%; p\\u0026thinsp;=\\u0026thinsp;0.038).\\u003c/p\\u003e \\u003cp\\u003eRegarding therapy, all TxC patients received combination treatment with corticosteroids and thionamides (100% vs. 47%; p\\u0026thinsp;=\\u0026thinsp;0.016).\\u003c/p\\u003e \\u003cp\\u003eThe mean time from the onset of AIT to the development of TxC was 55.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;10.1 days (median 57 days). The mean duration of thyrotoxic crisis until either acute thyroidectomy or remission was 8.4\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.7 days (median 8 days). Urgent thyroidectomy was necessary in 83% of TxC patients compared with 8% in the non-TxC group (p\\u0026thinsp;=\\u0026thinsp;0.0002). Elective thyroidectomy underwent 8 (18%) patients from non-TxC group.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eThe number of studies specifically addressing amiodarone-induced thyrotoxic crisis (TxC) remains very limited. Most available evidence focuses either on patients with AIT or on TxC of other etiologies (20). Although progression of AIT to TxC is rare, it represents a serious clinical scenario described mainly in isolated case reports. Systematic analyses of epidemiological, demographic, clinical, and therapeutic aspects would require long-term patient enrollment and prospective registries, which likely explains the scarcity of robust data and reviews. Moreover, the majority of published studies are retrospective, often spanning many years, which contributes to heterogeneity in patient populations, diagnostic criteria, and treatment strategies.\\u003c/p\\u003e \\u003cp\\u003eOur findings confirm the rarity of TxC in the context of AIT. Over a 20-year period, 55 patients with AIT were referred to our center, corresponding to an average of 2.8\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;1.9 cases per year (median 3/year). TxC was diagnosed in 6 patients (11%), with a mean incidence of 0.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.5 cases per year. Men constituted the majority of AIT patients overall (82%), and all TxC cases occurred in men.\\u003c/p\\u003e \\u003cp\\u003eAngell et al. (\\u003cspan citationid=\\\"CR20\\\" class=\\\"CitationRef\\\"\\u003e2015\\u003c/span\\u003e) retrospectively analyzed 150 patients with thyrotoxicosis, of whom 25 developed TxC. The male-to-female ratio was 53:97 in the entire cohort and 9:16 in the TxC subgroup. Reported etiologies included 75 patients with Graves\\u0026ndash;Basedow disease, 2 with AIT, 1 with toxic adenoma, 1 with multinodular goiter, and 80 without a determined cause. Female predominance was explained by the underlying etiologies, particularly autoimmune thyroid disease (20).\\u003c/p\\u003e \\u003cp\\u003eIn contrast, Kaderli et al. (\\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e2016\\u003c/span\\u003e) retrospectively analyzed 11 patients with AIT who underwent total thyroidectomy, all of whom were men. Reported thyroid function parameters at diagnosis were TSH\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.03 mIU/L and mean fT4 58.9 pmol/L (21). Our cohort showed similar findings, with mean TSH 0.006\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.008 mIU/L and mean fT4 57.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.5 pmol/L.\\u003c/p\\u003e \\u003cp\\u003eIn our TxC subgroup, 5 of 6 patients underwent urgent thyroidectomy. The mean interval from TxC onset to surgery was 7.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;5.6 days during florid thyrotoxicosis and severe cardiac failure. Remission with conservative therapy was achieved in one patient. Similarly, Kaderli et al. reported 11 AIT patients treated with total thyroidectomy after preoperative carbimazole, corticosteroids, and beta-blockers; plasmapheresis was used in one case. Only one patient was euthyroid before surgery. No major intra- or postoperative complications were observed, and none of the patients developed TxC or died (21).\\u003c/p\\u003e \\u003cp\\u003eTomisti et al. (\\u003cspan citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e2012\\u003c/span\\u003e) retrospectively studied 24 patients with AIT and left ventricular systolic dysfunction treated between 1997 and 2010. The mean age was 61 years, and overall mortality risk was high. Total thyroidectomy resulted in rapid improvement of clinical status, recovery of systolic function, and reduced mortality (22). In our cohort, the mean age was 57 years, and we also observed that urgent thyroidectomy in patients with TxC and advanced heart failure was associated with improved outcomes. Remission of TxC and AIT led to gradual recovery of left ventricular systolic function (22).\\u003c/p\\u003e \\u003cp\\u003eCapellani et al. (2020) retrospectively evaluated 207 AIT patients, including 51 who underwent thyroidectomy and 156 managed conservatively over a 20-year period. All causes and cardiac mortality at 5 and 10 years were significantly lower in the surgical group, particularly among patients with moderate-to-severe left ventricular dysfunction. In contrast, in those with preserved or only mildly reduced ejection fraction, mortality did not differ between surgical and medical management (23).\\u003c/p\\u003e \\u003cp\\u003eMore recent data support the role of early surgical intervention in selected high-risk patients with amiodarone-induced thyrotoxicosis. A contemporary cohort study by Frey et al. demonstrated that outcomes after total thyroidectomy are strongly influenced by baseline left ventricular systolic function, with the greatest benefit observed in patients with moderate-to-severe impairment of ejection fraction. These findings are consistent with our experience and suggest that, in patients with advanced cardiac disease, definitive surgical management may be advantageous when rapid control of thyrotoxicosis is required (24,25).\\u003c/p\\u003e \\u003cp\\u003eFinally, a French multicenter retrospective study (2020) analyzed 270 patients with thyrotoxicosis admitted to 31 intensive care units, 92 of whom developed TxC. Amiodarone exposure was the leading cause (n\\u0026thinsp;=\\u0026thinsp;30), followed by Graves\\u0026ndash;Basedow disease (n\\u0026thinsp;=\\u0026thinsp;24), toxic adenoma or multinodular goiter (n\\u0026thinsp;=\\u0026thinsp;38), autoimmune thyroiditis, and other etiologies. This large-scale analysis demonstrated that AIT constitutes a major risk factor for the development of TxC (25).\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eDespite ongoing research into new anti-arhythmic agents, amiodarone remains irreplaceable in clinical practice. Owing to its high iodine content, it predisposes susceptible individuals to thyroid dysfunction, with amiodarone-induced thyroid disorders among the most important complications of this otherwise highly effective drug.\\u003c/p\\u003e \\u003cp\\u003eAmiodarone-induced thyrotoxic crisis (TxC) is an extremely rare condition associated with exceptionally high clinical risk and significant mortality. Early recognition and prompt, comprehensive therapeutic intervention are decisive for patient survival. Combination therapy with antithyroid agents and corticosteroids forms the basis of treatment, while in selected cases acute thyroidectomy remains the only viable life-saving option. Optimal management requires close multidisciplinary collaboration and strict coordination of care to stabilize vital functions and address the underlying endocrine and cardiac pathology.\\u003c/p\\u003e \\u003cp\\u003ePatients with AIT are frequently burdened by advanced cardiac disease, which represents the key limiting factor for survival in the setting of TxC and restricts therapeutic options. Given the relatively small number of patients included in our cohort and the limited number of TxC cases, predictive factors cannot be confirmed with certainty. However, our findings suggest several potential clinical risk factors for the development of TxC in AIT: \\u003cb\\u003emale sex, younger age, markedly elevated maximum fT4 values (\\u0026gt;\\u0026thinsp;74.5 pmol/L), thyroid volume\\u0026thinsp;\\u0026gt;\\u0026thinsp;19 mL, mixed type of AIT, acute decompensation of preexisting cardiac disease, and atrial fibrillation with rapid ventricular response.\\u003c/b\\u003e No association was observed with the duration of amiodarone therapy, nor with average daily or cumulative dose.\\u003c/p\\u003e \\u003cp\\u003eEarly recognition and treatment of AIT are therefore essential to prevent progression to TxC, which remains a major clinical challenge for internists and cardiologists. Once TxC develops, only immediate and comprehensive interdisciplinary management can significantly improve its otherwise poor prognosis.\\u003c/p\\u003e \\u003cp\\u003eRegular monitoring of TSH, fT4, and fT3 in patients receiving amiodarone is therefore essential, as it enables the early detection of subclinical thyrotoxicosis and significantly influences disease severity and clinical outcomes.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003ch2\\u003eAuthor Contribution\\u003c/h2\\u003e\\u003cp\\u003eM.B. wrote the main text of the manuscript. M.B and A.B. conceived and designed the underlying scientific project.M.B and I.W. and Z.M. selected patients for inclusion and contributed with clinical management of patients. A.B. contributed with cardiology intensive care consultations and patients inclusion; performed the statistical analyses and preparate tables and graphs.N.P. contributed with scientific writing and analysis collected the scientific data.All authors reviewed the manuscript.All authors have read and agreed to the published version of the manuscript.\\u003c/p\\u003e\\u003ch2\\u003eData Availability\\u003c/h2\\u003e\\u003cp\\u003eAll data generated or analyzed during this study are included in this published article.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eFlorek JB, Lucas A, Girzadas D. Amiodarone. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eȘorodoc V, Indrei L, Dobroghii C, Asaftei A, Ceasovschih A, Constantin M, et al. Amiodarone therapy: updated practical insights. J Clin Med. 2024;13(20):6094.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eBrophy JM, Nadeau L. Amiodarone vs dronedarone for atrial fibrillation: a retrospective cohort study. CJC Open. 2022;5(1):8\\u0026ndash;14.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eKhitri AR, Aliot EM, Capucci A, Connolly SJ, Crijns H, Hohnloser SH, et al. Celivarone for maintenance of sinus rhythm and conversion of atrial fibrillation/flutter. J Cardiovasc Electrophysiol. 2012;23(5):462\\u0026ndash;72.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eDan GA, Martinez-Rubio A, Agewall S, et al. Antiarrhythmic drugs-clinical use and clinical decision making: a consensus document from the EHRA and ESC. Europace. 2018;20(5):738\\u0026ndash;45.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eTomisti L, Rossi G, Bartalena L, Martino E, et al. The onset time of amiodarone-induced thyrotoxicosis depends on AIT type. Eur J Endocrinol. 2014;171:363\\u0026ndash;8.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eBartalena L, Bogazzi F, Chiovato L, et al. European Thyroid Association guidelines for the management of amiodarone-associated thyroid dysfunction. Eur Thyroid J. 2018;7(2):55\\u0026ndash;66.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eShifrin AL, et al. Endocrine emergencies. 1st ed. Philadelphia: Elsevier; 2022.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eYlli D, Wartofsky L, Burman KD. Evaluation and treatment of amiodarone-induced thyroid disorders. J Clin Endocrinol Metab. 2021;106(1):226\\u0026ndash;36.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eRoss DS, Burch HB, Cooper DS, Greenlee MC, Laurberg P, Maia AL, et al. 2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis. Thyroid. 2016;26(10):1343\\u0026ndash;421.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eJameson JL, De Groot LJ. Endocrinology: adult and pediatric. 7th ed. Philadelphia: Elsevier; 2016.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eMedic F, Bakula M, Alfirevic M, Bakula M, Mucic K, Maric N. Amiodarone and thyroid dysfunction. Acta Clin Croat. 2022;61(2):327\\u0026ndash;41.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eHudzik B, Zubelewicz-Szkodzinska B. Amiodarone-related thyroid dysfunction. Intern Emerg Med. 2014;9(8):829\\u0026ndash;39.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eTsang W, Houlden RL. Amiodarone-induced thyrotoxicosis: a review. Can J Cardiol. 2009;25(7):421\\u0026ndash;4.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eO\\u0026rsquo;Sullivan AJ, Lewis M, Diamond T. Amiodarone-induced thyrotoxicosis: left ventricular dysfunction is associated with increased mortality. Eur J Endocrinol. 2006;154(4):533\\u0026ndash;6.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eVinan-Vega M, Mantilla B, Jahan N, Peminda C, Nugent K, Lado-Abeal J, et al. Usefulness of plasmapheresis in patients with severe complicated thyrotoxicosis. Proc Bayl Univ Med Cent. 2020;34(2):279\\u0026ndash;82.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003ePodoba J, Zajacov\\u0026aacute; H. Amiodaron a poruchy funkcie št\\u0026iacute;tnej žľazy. Cardiology. 2000;9:20\\u0026ndash;4.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eMaqdasy S, Benichou T, Dallel S, Roche B, Desbiez F, Montanier N, et al. Issues in amiodarone-induced thyrotoxicosis: update and review. Ann Endocrinol (Paris). 2019;80(1):54\\u0026ndash;60.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAkamizu T, Satoh T, Isozaki O, et al. Diagnostic criteria, clinical features, and incidence of thyroid storm based on nationwide surveys. Thyroid. 2012;22(7):661\\u0026ndash;79.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAngell TE, Lechner MG, Nguyen CT, et al. Clinical features and hospital outcomes in thyroid storm: a retrospective cohort study. J Clin Endocrinol Metab. 2015;100(2):451\\u0026ndash;9.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eKaderli RM, Fahrner R, Christ ER, et al. Total thyroidectomy for amiodarone-induced thyrotoxicosis in the hyperthyroid state. Exp Clin Endocrinol Diabetes. 2016;124(1):45\\u0026ndash;8.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eTomisti L, Materazzi G, Bartalena L, et al. Total thyroidectomy in patients with amiodarone-induced thyrotoxicosis and severe LV dysfunction. J Clin Endocrinol Metab. 2012;97(10):3515\\u0026ndash;21.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eCappellani D, Papini P, Pingitore A, et al. Comparison between total thyroidectomy and medical therapy for amiodarone-induced thyrotoxicosis. J Clin Endocrinol Metab. 2020;105(1):41\\u0026ndash;9.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eFrey S, Kaderli RM, Christ ER, et al. Mortality after total thyroidectomy for amiodarone-induced thyrotoxicosis according to left ventricular ejection fraction. Eur J Endocrinol. 2023;188(6):789\\u0026ndash;798.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eFrey S, Kaderli RM, Staub JJ, et al. Amiodarone-induced thyrotoxicosis: is surgery underutilized in high-risk patients? Am J Cardiol. 2024;195:112\\u0026ndash;119.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eBourcier S, Coutrot M, Kimmoun A, et al. Thyroid storm in the ICU: a retrospective multicenter study. Crit Care Med. 2020;48(1):83\\u0026ndash;90.\\u003c/span\\u003e\\u003c/li\\u003e\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bratislava-medical-journal\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"Learn more about [Bratislava Medical Journal](https://link.springer.com/journal/44411)\",\"snPcode\":\"44411\",\"submissionUrl\":\"https://submission.springernature.com/new-submission/44411/3\",\"title\":\"Bratislava Medical Journal\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"stoa\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-8816835/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-8816835/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003ch2\\u003eBackground\\u003c/h2\\u003e \\u003cp\\u003eAmiodarone-induced thyrotoxicosis (AIT) is a serious complication of long-term amiodarone therapy. Its most severe manifestation is thyrotoxic crisis (TxC), a rare but life-threatening condition associated with high morbidity and mortality.\\u003c/p\\u003e\\u003ch2\\u003eAim\\u003c/h2\\u003e \\u003cp\\u003eTo analyze patients with AIT, identify demographic and clinical parameters, evaluate diagnostic and therapeutic approaches, and determine predictive risk factors for TxC.\\u003c/p\\u003e\\u003ch2\\u003eMethods\\u003c/h2\\u003e \\u003cp\\u003eA retrospective study of 55 consecutive patients with confirmed AIT followed between 2005 and 2024. Baseline characteristics, laboratory findings, thyroid ultrasound, clinical presentation, therapy and outcomes were analyzed. Patients were classified into AIT type I, type II, or mixed type. TxC was diagnosed using the Burch\\u0026ndash;Wartofsky scoring system.\\u003c/p\\u003e\\u003ch2\\u003eResults\\u003c/h2\\u003e \\u003cp\\u003eThe cohort included 45 men (82%) and 10 women (18%), mean age 62.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;9.9 years. Amiodarone was prescribed mainly for atrial fibrillation (78%). Mean duration of therapy until AIT onset was 988\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;502 days. At diagnosis, mean fT4 was 43.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;18.3 pmol/L and mean TSH 0.017\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;0.052 mIU/L. Thyroid volume averaged 18.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;8.7 mL, and goiter was present in 47% of patients. AIT types were distributed as follows: type I in 23%, type II in 44%, and mixed type in 33%. Six patients (11%) developed TxC, all men, with higher maximum fT4 (\\u0026gt;\\u0026thinsp;74.5 pmol/L), larger thyroid volume (\\u0026gt;\\u0026thinsp;19 mL), and more frequent atrial fibrillation with rapid ventricular response. Urgent thyroidectomy was required in 5 of 6 cases with TxC.\\u003c/p\\u003e\\u003ch2\\u003eConclusion\\u003c/h2\\u003e \\u003cp\\u003eAIT is a clinically important complication of amiodarone therapy. Male sex, younger age, large thyroid volume, high maximum fT4, mixed AIT type, and cardiac decompensation are supposed clinical risk factors for TxC. Early recognition and interdisciplinary management are crucial to improve outcomes.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Amiodarone-Induced Thyrotoxicosis and Clinical Risk Factors for Thyrotoxic Crisis\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2026-02-16 06:59:41\",\"doi\":\"10.21203/rs.3.rs-8816835/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2026-03-02T15:32:01+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-02-25T14:35:28+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"244991418722955733865831951765535969606\",\"date\":\"2026-02-24T12:11:27+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"188746523921495663889584171820872059980\",\"date\":\"2026-02-11T21:02:52+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2026-02-10T11:04:23+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2026-02-09T13:26:39+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2026-02-09T13:21:19+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Bratislava Medical Journal\",\"date\":\"2026-02-07T16:01:40+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bratislava-medical-journal\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"Learn more about [Bratislava Medical Journal](https://link.springer.com/journal/44411)\",\"snPcode\":\"44411\",\"submissionUrl\":\"https://submission.springernature.com/new-submission/44411/3\",\"title\":\"Bratislava Medical Journal\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"stoa\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"a6827b3e-3f26-47f0-a6e3-e94afcfbd089\",\"owner\":[],\"postedDate\":\"February 16th, 2026\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2026-03-17T11:40:10+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2026-02-16 06:59:41\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-8816835\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-8816835\",\"identity\":\"rs-8816835\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}