Surgical Outcome for Tetralogy of Fallot in an African Setting; a Tanzanian Experience Using Retrospective Analysis of Hospital Data

Surgical Outcome for Tetralogy of Fallot in an African Setting; a Tanzanian Experience Using Retrospective Analysis of Hospital Data | 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 Surgical Outcome for Tetralogy of Fallot in an African Setting; a Tanzanian Experience Using Retrospective Analysis of Hospital Data Naizihijwa Majani, Godwin Sharau, Vivienne Mlawi, Zawadi Kalezi, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4422562/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Sep, 2024 Read the published version in BMC Cardiovascular Disorders → Version 1 posted 13 You are reading this latest preprint version Abstract Background: Tetralogy of Fallot (TOF) is typically treated in infancy but often done late in many resource-limited countries, jeopardizing surgical outcomes. This study examined the results of TOF repair surgery at the Jakaya Kikwete Cardiac Institute (JKCI) in Tanzania, an emerging cardiac centre in Eastern Africa. Methods: A retrospective cohort study of children <18 years with TOF post-surgical repair between 2019 and 2021 was conducted. Data on socio-demography, pre-and postoperative cardiac complications, Intensive Care Unit (ICU) and hospital stay, and in-hospital and 30-day mortality were analyzed. Logistic regressions were employed to find the factors for mortality, ICU, and hospital stays. Results: The I07 children operated on were majority male (62.3%), with a median age of 3.0 years (IQR: 2- 6). Almost all (90%) were underweight, with a mean BMI of 14.6 + 3.1 kg/m 2 . Only 18.7% were below one year of age. Haematocrits were high, with a median of 48.7 (IQR: 37.4-59.0). Bacterial sepsis was more common than surgical site infection (5.6% vs 0.9%). The median oxygen saturation was 81% (IQR:72-93). The median ICU stay was 72 hours (IQR:48-120), with ICU duration exceeding three days for most patients. The median hospital stay was 8.5 days (IQR:7-11), with 66% experiencing an extended hospital stay of > 7 days. The in-hospital mortality rate was 10.3%, with no deaths occurring in children less than one year of age nor after discharge during the 30-day follow-up period. No statistically significant differences were observed in outcomes in relation to clinical and demographic characteristics. Conclusion: TOF repairs in an African setting face challenges associated with patients' older age and compromised nutritional status during the surgery. Perioperative mortality rates and morbidity for patients operated at an older age remain elevated. It’s important to address these issues to improve outcomes in these settings. Tetralogy of Fallot Surgical outcomes Low-middle-income setting Highlights This study examined the clinical characteristics and 30-day surgical outcomes of patients with Tetralogy of Fallot who were treated in a low-middle-income setting Study Limitations: Single center retrospective study Lack of Echocardiography data to access TOF severity Study Strength: Adequate sample size compared to available study in the literature looking at TOF repair in African settings, with most having sample size of less than 100 patients. Introduction Tetralogy of Fallot (TOF) is the most frequent cyanotic cardiac condition. It occurs in 0.34 per 1,000 live births and accounts for 7–10% of all congenital heart disease (CHD) [ 1 ]. The severity of TOF depends on the degree of right ventricular outflow tract (RVOT) obstruction and the anatomy of pulmonary vasculature [ 2 ]. Surgery is the definitive treatment of TOF [ 1 , 2 ]. The recommended age for surgical repair is now 3–6 months, and best within the first year of life [ 3 ]. Most centers reserve neonatal surgery for infants with hypercyanotic spells or severe cyanosis [ 4 ]. Early surgery can help avoid complications, conclude experts [ 3 , 4 , 5 ]. The overall outcome of TOF repair in developed regions is good, and the mortality rate is less than 3% [ 6 , 9 ]. In High-Income country (HIC) settings, over 90% of operated children with TOF are below the age of one year [ 5 ]. However, in most developing nations, a typical TOF patient will present past the recommended age of surgical repair [ 7 ]. Ngwezi and colleagues (2013) documented that they operated on only 32% of TOF patients in infancy in their series in South Africa [ 8 ]. The reported operative mortality of late complete repair of TOF in children beyond infancy ranges from 6.9-to 15% [ 18 ]. The perioperative outcome is determined by the patient's characteristics and the centre’s related factors, including but not limited to disease severity, age at operation, oxygen saturation level and presence of comorbidities. Data shows that repairing TOF in infancy results in fewer postoperative issues and shorter hospital stays [ 10 , 11 ]. Due to the scarcity of cardiac centers in low- and middle-income countries (LMIC), there is an increased number of unrepaired CHD, with Africa recording the highest burden of unrepaired CHD globally [ 37 ]. The accumulation of unrepaired TOF in these settings poses a challenge, and careful case selection is imperative to ensure that patients who will maximally benefit get treated. Determining drivers of successful surgical outcomes in developing countries is therefore necessary. This study assesses the clinical characteristics and 30-day surgical outcomes of patients with TOF at JKCI in Dar es Salaam from 2019 to 2021. We hypothesize that due to the lack of systematic screening for CHD in Tanzania, most patient will be operated on late, and their outcome may be suboptimal. The study was approved by the Jakaya Kikwete Institutional review board with IRB number AB.123/196/01/H7, and we followed the ethical guidelines stated in the 1975 Declaration of Helsinki. As this was a retrospective study, the IRB granted a waiver for consent. Methods Study Setting The Jakaya Kikwete Cardiac Institute, JKCI, is a specialized National Referral Hospital and the only public Institute treating children with CHD since 2015. Located In Eastern Africa, Tanzania, JKCI has a typical LMIC setting. The Institute's experience can help answer pertinent questions regarding TOF repair in the region. The center provides cardiac surgery for adults and children. Pediatric cardiac surgery was established in 2015 by the local team and with the support of regular visits from international teams. Over 80% of surgeries were performed by the local team at the time of this study. Between 2019 and 2021, approximately 1,794 children were diagnosed with CHD and seen in the outpatient department (OPD) for the first time, out of which 180 were diagnosed with TOF (local database). The centre performs about 200 surgeries on children annually (unpublished local database); however, the capacity is insufficient to treat and operate all children. Patient selection follows the Institute protocol after discussion in the interdisciplinary meeting. Depending on the stage and anatomical characteristics, patients with TOF can undergo complete or palliative repair with a Blalock Tausing (BT )shunt. Study Design This retrospective study evaluated patient characteristics, postoperative morbidity and mortality of patients who underwent TOF repair at JKCI. The study also examined the risk factors associated with the operative outcomes. Study Sample We included all patients diagnosed with TOF and who underwent surgery at JKCI between January 2019 and December 2021. Patients with pulmonary atresia, an absent pulmonary valve, or common atrioventricular canal defects were excluded from the study because these conditions have different disease progression and management. Data Measurement In 2019, JKCI joined the International Quality Improvement Collaborative for Congenital Heart Disease (IQIC). A structured questionnaire designed by IQIC was employed to systematically collect information [ 36 ]. The study data was collected and managed using the REDCap (Research Electronic Data Capture) ver.16 hosted at JKCI [ 33 , 34 , 35 ]. Medical officers input the data into REDCap, under the supervision of Pediatric Cardiologists. Each user is assigned an individual user ID and password, with access tailored to their specific role. All children undergoing congenital heart surgery are enrolled upon admission, and case report forms 1–5 are completed. (For examples of case report forms, please refer to Appendix D). Case report form 6 is filled out during the 30-day follow-up visit. The JKCI's IQIC database undergoes an annual check by the Boston University team to ensure quality assurance and validity. The data-capturing tool focuses on factors such as nutritional status, prematurity, age, surgical procedure, co-morbidities, and outcomes, including mortality and infections. Preoperative characteristics recorded in this study encompass hematocrit levels, oxygen saturation, weight, and age. The WHO weight-for-age charts categorise weight as either normal for age or underweight [ 33 ]. We measured surgical outcomes based on death rates, ICU and hospital stays. We considered stays longer than three days in the ICU and longer than seven days in the hospital to be lengthy [ 31 ]. Postoperative complications include wound infection, sepsis, bleeding, and reoperation. Additionally, patients were assessed for the presence of major medical illnesses, such as diabetes, sickle cell disease, HIV/AIDS, and malaria. The presence of any of these conditions was duly noted. Monitoring was conducted to identify any cardiopulmonary bypass (CPB)-related events. Any event that resulted in a patient undergoing re-operation was classified as a CPB-related event. Patients who displayed signs and symptoms of blood infection or surgical site infection and either underwent bacteriological testing or required an extension of antibiotic usage were carefully observed and labelled as cases of sepsis. Patients with more than 80% of missing data were excluded from the study. Data Analysis Data was extracted from REDCap to SPSS and analyzed using Stata statistical software, version 17. Both descriptive and analytical techniques were employed. Frequencies and percentages were used to summarize categorical data. Continuous data are presented as the means with standard deviations and medians with interquartile ranges (25th, 75th). Contingency tables were used to present cross-tabulations between the dependent and the independent variables. Mean tests were performed using independent sample t-tests, while Mann-Whitney was used to test differences in medians between samples. We used the chi-square and Fisher’s exact tests (as appropriate) to assess the associations between categorical variables. If p < 0.05, the associations were considered significant. We used logistic regressions to determine factors related to mortality and lengths of stay. We considered factors with a p-value < 0.2 in multivariable models using logistic regressions. We calculated crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). We reported all variables in the model with p values < 0.05 as factors for in-hospital mortality or length of hospital stay. Results Baseline characteristics of the operated TOF Patients Table 1 shows the demographic characteristics of the patients. Between January 2019 and December 2021, the team operated on 428 children out of these 107 children (22.1%) had TOF and aged between 1 and 18 years, predominantly male 62.6%, and male to female ration of 1.7:1. The median age at operation was 3.0 years (IQR: 2–6), with over half of patients (n = 60; 56.1%) being in the age range of 1–5 years and only 18.7% younger than one year of age. Over 90% of patients were underweight, and the mean BMI was 14.6 + 3.1 kg/m2. The prematurity rate in the entire cohort was low at 2% compared to the national average of 11% [ 32 ]. There was no CPB-related event recorded. Open Chest and Surgical bleeding rates were 1.9% and 2.8%, respectively. Only 4.7% had genetic syndrome, and medical illness was recorded in 2.8%. Bacteria sepsis was more common than surgical site infection (5.6% vs 0.9%). The median preoperative oxygen saturation was 81% (72,93), and almost one-third of the patients had less than 75% oxygen saturation values. Over a third of patients had hematocrits greater than 55%, with a median hematocrit of 48.7% IQR (37.4, 69.0). Slightly more than a third of the patients who underwent surgery 36.4% required a transannular patch. Immediate surgical outcomes by the age of operation Eleven patients died during the study period giving a mortality rate of 10.3%. All deaths occurred before discharge from the hospital, and there was no mortality in the group younger than the age of one year. The median ICU stay was 72 hours (48,120). On average, over two-thirds of patients stayed in hospital for more than seven days; the median days of hospital stay were 8.5 (7,11), Table 2 . Differences in clinical characteristics between early and late repair Twenty patients with TOF (18.7%), underwent surgery before the age of one year. Patients older than one year had higher hematocrits, with 50% having hematocrits greater than 55%. Older children were more cyanosed, with 31% having a saturation level less than 75% vs 20%; these differences were not statistically significant. The comorbidities were similar between TOF patients irrespective of age, except for a slight tendency toward lower hematocrit levels in those operated on after less than one year (Supplementary Appendix C). Factors associated with in-hospital mortality outcome for TOF patients Table 3 displays the baseline characteristics that were associated with in-hospital mortality. In the univariate analysis, some factors were found to have higher odds of in-hospital mortality, but none of these factors were statistically significant. These factors included female sex (OR = 1.4 [0.45–4.30]), genetic syndrome (OR = 2.04 [0.32–13.08]), saturation below 75% (OR = 1.93 [0.635–0.89]) and transannular patch use (OR = 3.05 [0.95–9.82]). Additionally, the odds of dying were 2.02 (odds ratio [OR] 2.02 [0.41–9.97]) for children with hematocrit levels greater than 55%. Factors associated with length of hospital and ICU stay among operated TOF patients It was observed that certain baseline characteristics were associated with a higher chance of longer hospital stays, but none of them were statistically significant. The characteristics that indicated higher odds were males (OR = 1.33 [0.85–2.10]), age younger than one year (OR = 1.24 [0.76–2.03]), underweight (OR = 1.38 [0.60–3.18]), hematocrit above 55% (OR = 1.45 [0.95–2.20]), and saturations below 75% (OR = 1.16 [0.77–1.74]). The use of TAP was found to increase the length of hospital stay by 1.25 times (0.84–1.85). It is worth noting that all patients stayed in ICU for over 72 hours. (Table 4 ). Table 1 Baseline clinical characteristics of children with TOF repair at the JKCI, N = 107 Characteristics Frequency Percent Male 67 62.6 Age at Surgery (years) Median (IQR) 3 (2, 6) Less a year 20 18.7 1–5 60 56.1 6+ 27 25.2 BMI a Mean (SD) 14.5 (3.1) Underweight 91 90.1 Normal weight 9 8.9 Overweight 1 1.0 Prematurity 1 1.0 Genetic Syndrome 5 4.7 Medical Illness 3 2.8 CPB Related Event 0 0.0 Open Chest 2 1.9 Infection Bacterial Sepsis 6 5.6 Infection Surgical Site 1 0.9 Complication Surgery for Bleeding 3 2.8 Hematocrits c Median (IQR) 48.7 (37.4, 59.0) < 55 60 63.8 Saturation Median (IQR) 80 (72, 93) < 75% 32 30.2 IQR-Interquartile Range, BMI-Body Mass IndexSD-Standard Deviation, CPB- Cardiopulmonary Bypass, SD = Standard deviation, TOF = Tetralogy of Fallot, kg = weight in kilograms Table 2 Clinical Outcomes among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N = 107 Outcome In hospital mortality (n, %) 11 (10.3%) Length of ICU stay (> 72 hours) 60 (98.4%) Median length of ICU stays in hours (IQR) 72 (48, 120) Length of hospital days (7 days) 70 (66.0%) Median Length of hospital days (IQR) 8.5 (7–11) Note: Long ICU stay defined as more than 72hours and Long hospital stay as more than seven days. No Mortality occurred after hospital discharge. Table 3 Factors associated with in-hospital mortality among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N = 107 Factor Number n (%) In hospital mortality n (%) Crude OR (95%CI) Adjusted OR (95%CI) Sex (Female) 40 (37.4) 5 (12.5) 1.40 (0.45–4.30) 0.74 (0.25–2.21) Age (years) > 1 87 (92.5) 11 (12.6) BMI Underweight 98 (91.0) 11 (9.9) Genetic Syndrome( Yes) Yes 5 (4.7) 1 (20) 2.04 (0.32–13.08) Medical Illness Yes 3 (2.8) 0 (0) No 104 (97.2) 11 (10.6) Hematocrits > 55 45 (44.7) 2 (4.4) 0.71 (0.14–3.47) Saturation < 75% 33 (30.2) 5 (15.1) 1.93 (0.63–5.89) Transannular patch Yes 39 (36.4) 7 (18.0) 3.05 (0.95–9.82) 3.23 (0.95-11.0) Table 4 Factors for length of hospital stay among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N = 107 Factor Number n (%) Length of hospital stay n (%) Crude OR (95%CI) Adjusted OR (95%CI) Sex Male 64 (64.0) 22 (73.3) 1.33 (0.85–2.10) 1.25 (0.83–1.87) Age (years) 50 42(40.4) 12 (28.5) 0.79 (0.52–1.22) 0.79 (0.51–1.21) Saturation 75+% 74 (71.5) 24 (32.4) 1.16 (0.77–1.74) Transannular patch Yes 36 (34.6) 15 (41.6) 1.25 (0.84–1.85) Discussion Our study focused on the surgical outcome of Tetralogy of Fallot patients from Tanzania. In this cohort, TOF accounts for nearly a quarter (22.1%) of all operated patients; highlighting the substantial burden of TOF in this setting. Although there is not much documentation on the burden of TOF in LMIC, experts estimate that it is consistent with the global prevalence, where TOF makes up 7–10% of all CHD cases [ 1 ]. The excess proportion we see in our cohort may be for reasons of survival ship. Without surgery, 90% of children with CHD and TOF die within ten years, but 66% survive the first year of life [ 12 ]. We speculate that due to a lack of systematic screening for CHD, the patients we encounter in our settings represent milder forms of the disease, the survivors, while more severe cases perish at a young age before receiving a diagnosis, underscoring the importance of early detection through screening programs. Our cohort's median age at repair was three years. As anticipated, only 18.7% of patients who underwent TOF were younger than one year of age. In developed countries, in contrast, more than 90% of operations are conducted on patients younger than one year of age [ 13 ]. Age at repair is important. The Toronto group reported the safety of surgery between 3 and 11 months of age, while a risk of death was associated with surgery at 12 + months [ 14 ]. Our study confirmed these findings, as no mortalities were observed before one year of age. Nevertheless, a later age for TOF repair is a common trend in most developing nations. In Iran, the mean age of operation for TOF patients was four years. In Brazil, a cohort of 83 TOF patients had a mean age at operation of 3.7 years. Similarly, Turkey's mean age at operation was 2.3 years [ 15 , 16 , and 17 ]. Insufficient screening and access to echocardiography in rural health canters of developing countries act as barriers to early detection and treatment. Early repair is crucial as it can alleviate the effects of cyanosis and protect vital organs. Additionally, early repair prevents the obstruction of the right ventricular outflow tract (RVOT) caused by fibrosis, a risk factor for poor outcomes [ 18 ]. Consequently, patients in LMICs who undergo surgery at a later stage due to delayed presentation are more likely to experience unfavorable outcomes. In our cohort, the mortality rate for TOF patients was 10.3%, and all fatalities occurred within the hospital. This is consistent with the reported mortality rates of 6.9–15% in developing countries [ 18 ]. For instance, in Ethiopia, a study involving 62 TOF patients operated between 2009 and 2014 reported a mortality rate of 12.9% [ 19 ]. Tchoumi et al. studied 22 TOF patients who underwent complete repair surgery by a visiting team. The average age of the patients was 9.2 ± 6.5 years, and the mortality rate was 9% [ 20 ]. Similarly, in a study by Benbrik et al., complete repair of TOF was performed on 47 children from developing countries at a mean age of 4.8 ± 3.2 years, with a postoperative mortality rate of 4.2% [ 21 ]. However, an interesting contrast can be seen in Pakistan, where Waqar et al. reported on a large cohort of 307 children who underwent TOF repair at a mean age of 9.6 ± 4.9 years. The 30-day mortality rate in that study was 1.3%, similar to rates reported in developed nations [ 22 ]. In Europe and North America, perioperative mortality for TOF is less than 3% due to improved management strategies [ 2 ]. The outcomes observed in various developing countries can partially be attributed to the experience and expertise of the healthcare centers and systemic factors outside the disease that contribute to higher mortality rates [ 22 ]. This was demonstrated in a cohort of 47 African patients who were operated on in France, which exhibited a low mortality rate of 3.2%, comparable to that of local patients, despite being older than the 90 French patients [ 21 ]. Therefore, as emerging centers in low- and middle-income countries gain more experience and handle larger patient volumes, we expect improved outcomes over time. Although Tetralogy of Fallot is more common in males according to the literature and was shown in our data set to be 62.6%, female sex in our cohort was associated with 40% higher hospital mortality. We are unaware of any reports indicating higher mortality rates for females following TOF repair. However, historical reports have indicated that females are at a high risk of death postcardiac surgery [ 23 ]. Chang and Klitzner were the first to show sex differences in-hospital mortality in children undergoing cardiac CHD surgery; using data from 1989 to 1999 in California, in their study, the female sex was associated with an 18% greater risk of death [ 24 ]. A US population study examining sex differences in CHD surgical outcomes showed that female in-hospital mortality was 21% greater [ 25 ]. The cause of excess mortality in females is unclear [ 23 , 24 , 25 ]. Surgical mortality is influenced by the severity of the disease. In the case of patients with Tetralogy of Fallot (TOF) who experience deep cyanosis and higher hematocrit levels, their condition is more critical. In our study, we found that children with hematocrit levels exceeding 55% and a haemoglobin saturation below 75% was at a higher risk of mortality and experienced longer stays in the ICU and hospital. A study conducted in Houston, Texas, between 1954 and 1962, involving 203 patients with TOF, demonstrated that a high hematocrit was a reliable risk indicator. Patients with a hematocrit greater than 55% had a mortality rate of 31%, while those below 55% had a mortality rate of 10% [ 26 ]. Furthermore, a Turkish study revealed a connection between higher hematocrit levels and unfavorable outcomes, including extended hospital stays, prolonged mechanical ventilation, prolonged ICU stays, and increased occurrence of major adverse effects [ 27 ]. In Houston, a successful approach to reducing mortality in TOF surgeries involved using a Blalock-Taussig (BT) shunt to lower hemoglobin concentration from above 18 gm to below 18 gm [ 26 ]. Recent studies utilizing machine learning to assess perioperative predictors of TOF outcomes have suggested that preserving right ventricular remodeling and optimizing hematocrit levels are effective strategies [ 28 ]. Therefore, for patients presenting late with deep cyanosis and high hematocrit levels in low- and middle-income countries (LMICs) who undergo palliation and delayed surgery, the use of a BT shunt could be a preferable strategy [ 26 , 28 ]. The need for trans-annular patches (TAPs) for TOF repairs can indicate disease severity and technical difficulties, resulting in longer bypass times and ICU and hospital stay [ 28 ]. In our series, TAP patients were three times more likely to experience fatal outcomes. These findings are consistent with many studies in the literature. Surgeons in North America frequently use ventriculotomy and TAP for TOF repair [ 29 ]. In Europe, TAP techniques were associated with increased mortality [ 30 ]. Notably, although desirable, valve-sparing is not achievable in most settings [ 29 , 30 ]. Therefore, teams must understand the risks of TOF patients receiving TAP to provide optimal care. Lastly, TOF patients had slightly different characteristics than others who underwent congenital surgery at the Centre during the same period. TOF patients had higher average weight values and experienced more postsurgical bleeding and sepsis but also had increased levels of cyanosis and hematocrit (supplementary material appendix A and B). Understandably, these differences are due to the complexities associated with the TOF condition. Comparably, however, all patients treated at the same cardiac institute were late presenters. These findings, in general, indicate that there is still room for improvement in the management of CHD and particularly TOF. Nonetheless, they also highlight the resilience and dedication of patients and medical professionals in the face of challenging circumstances. Summary Our data set highlights the importance of early detection for CHD. By implementing a systematic screening process for CHD, including TOF, more severe cases can be identified and diagnosed earlier. Additionally, recognizing the risk factors associated with TOF and implementing strategies like bridging repair with a BT shunt and systematic screening processes for CHD may contribute to excellent outcomes, reduced mortality, shorter ICU and hospital stays, and improved survival rates for individuals with TOF in LMIC. Limitations To the best of our knowledge, this study represents the first examination of factors related to mortality in Tanzania, specifically for the total correction of TOF. However, it is important to acknowledge that this study is based on a single centre, potentially limiting its findings' generalizability to other settings. Nevertheless, the results hold significance since the Jakaya Kikwete Cardiac Institute (JKCI) currently stands as the sole center providing cardiac care for children in the country. One limitation of this study is the unavailability of echocardiography data, which rendered the classification of TOF severity impossible. Consequently, the researchers resorted to using TAP (Trans Annular Patch) as a means to indicate severe TOF. Moreover, this investigation did not account for additional influential factors such as surgical expertise or intensive care unit (ICU) experience, which could potentially impact outcomes. Notwithstanding these limitations, the study offers valuable insights into the prevailing circumstances faced by TOF patients at the National Referral Center while identifying immediate factors clinicians within this facility can utilize to enhance outcomes. However, it is crucial to recognize that this study underscores the necessity for a prospective study, encompassing a comprehensive analysis of all factors associated with outcomes, to gain a deeper understanding of this commonly occurring CHD within the Tanzanian context. Conclusion Repair of TOF in African settings is characterized by older age and poor nutritional status during surgery, leading to high perioperative mortality and morbidity. This study underscores the importance of addressing these issues to improve the surgical outcomes of TOF repairs in resource-limited regions. Declarations Ethics approval and consent to participate The Jakaya Kikwete Institutional Review Board reviewed and approved the study, with Institutional review board number AB.123/196/01/H7. The Jakaya Kikwete Institutional review board waived the need for informed consent because of the study's retrospective nature. Consent for publication Not applicable Competing interests None to declare Funding There was no funding for this study Availability of data and materials The authors will make the raw data supporting the conclusions of this article available without undue reservation, upon reasonable request to the first Author Naizihijwa Majani. Author Contributions NM contributed to the conception and design of the study. GS, VM, SM, NL, DN, and SK collected data and organized the database. NM performed the statistical analysis together with ZK. NM, MS, and PC were involved in the study and interpretation of the data. MJ, DG, and PK supervised the study. NM wrote the first draft of the manuscript. All the authors reviewed and edited all the manuscript sections and read and approved the submitted version. Acknowledgement We thank the Department of Pediatric Cardiac Surgery, the Division of Pediatric Cardiology, and the Pediatric ICU for their unwavering care of children with congenital heart disease despite limited resources. We also acknowledge Winnie Msakyusa and Jackline Oseti for contributing to data entry in the surgical database. References Bailliard F, Anderson RH. Tetralogy of Fallot. Orphanet J Rare Dis. 2009;4:2. Published 2009 Jan 13. Van der Ven JPG, van den Bosch E, Bogers AJCC, Helbing WA. Current outcomes and treatment of tetralogy of Fallot. F1000Res. 2019;8: F1000 Faculty Rev-1530. Published 2019 Aug 29. Mouws EMJP, de Groot NMS, van de Woestijne PC, de Jong PL, Helbing WA, van Beynum IM, Bogers AJJC. Tetralogy of Fallot in the Current Era. Semin Thorac Cardiovasc Surg. 2019;31(3):496–504. https://doi.org/10.1053/j.semtcvs.2018.10.015 . Loomba RS, Buelow MW, Woods RK. Complete Repair of Tetralogy of Fallot in the Neonatal Versus Nonneonatal Period: A Meta-analysis. Pediatr Cardiol. 2017;38(5):893–901. Valente AM, Gauvreau K, Assenza GE, et al. Contemporary predictors of death and sustained ventricular tachycardia in patients with repaired tetralogy of Fallot enrolled in the INDICATOR cohort. Heart. 2014;100(3):247–53. van der Ven JPG, van den Bosch E, Bogers AJCC, Helbing WA. (2019). Current outcomes and treatment of tetralogy of fallot [version 1; peer review: 2 approved]. F1000Research , 8 , 1–15. https://doi.org/10.12688/f1000research.17174.1 . Sandoval N, Carreño M, Novick WM, Agarwal R, Ahmed I, Balachandran R, Balestrini M, Cherian KM, Croti U, Du X, Gauvreau K, Cam Giang DT, Shastri R, Jenkins KJ. Tetralogy of Fallot Repair in Developing Countries: International Quality Improvement Collaborative. Ann Thorac Surg. 2018;106(5):1446–51. https://doi.org/10.1016/j.athoracsur.2018.05.080 . Ngwezi DP, Vanderdonck K, Levin SE, Cilliers A. An audit of surgical repair of Tetralogy of Fallot in an African tertiary care center. SA Heart. 2013;10(3):520–5. Juliana J, Sembiring YE, Rahman MA, Soebroto H. Mortality Risk Factors in Tetralogy of Fallot Patients Undergoing Total Correction. Folia Med Indonesiana. 2021;57(2):151. https://doi.org/10.20473/fmi.v57i2.22107 . Saygi M, Ergul Y, Tola HT, et al. Factors affecting perioperative mortality in tetralogy of Fallot. Pediatr Int. 2015;57(5):832–9. Gerling C, Rukosujew A, Kehl. Do the Age of Patients with Tetralogy of Fallot at the Time of Surgery and the Applied Surgical Technique Influence the Reoperation Rate? Herz. 2009;34:155–60. Bertranou EG, Blackstone EH, Hazelrig JB, Turner ME, Kirklin JW. (1978). Life expectancy without surgery in tetralogy of Fallot. Am. J. Cardiol . 42 (3): 458–66. 10.1016/0002-9149(78)90941-4 . PMID 685856. Hashemzadeh K, Hashemzadeh S (2010). Early and late results of total correction of tetralogy of Fallot. Acta Med Iranica 48, 117- 122. Van Dongen EI, Glansdorp AG, Mildner RJ, McCrindle BW, Sakopoulos AG, VanArsdell G, Williams WG, Bohn D. The influence of perioperative factors on outcomes in children aged less than 18 months after repair of tetralogy of Fallot. J Thorac Cardiovasc Surg. 2003;126(3):703–10. https://doi.org/10.1016/S0022-5223(03)00035-7 . Sarris GE, Coma + s JV, Toyota Z, et al. Results of reparative surgery for tetralogy of Fallot: data from the European Association for Cardio-Thoracic Surgery Congenital Database. Eur J Cardiothorac Surg. 2012;42(5):766–74. Azari A, Nezafati MH, Bigdelu L. Early post operative mortality of Total Correction of Tetralogy of Fallot. J Cardio-Thoracic Med. 2017;5(4):222–5. Pinheiro P, de Azevedo S, V. M. P., Rocha G. Predicting Factors of Surgical Mortality in Children and Adolescents Undergoing Correction of Tetralogy of Fallot. Int J Cardiovasc Sci. 2023;36:1–11. https://doi.org/10.36660/ijcs.20200394 . Saygi M, Ergul Y, Tola HT, Ozyilmaz I, Ozturk E, Onan IS, Haydin S, Erek E, Yeniterzi M, Guzeltas A, Odemis E, Bakir I. Factors affecting perioperative mortality in tetralogy of Fallot. Pediatr Int. 2015;57(5):832–9. https://doi.org/10.1111/ped.12627 . Hashemzadeh K, Hashemzadeh S. Early and late results of total correction of tetralogy of fallot. Acta Medica Iranica. 2010;48(2):117–22. Tefera E, Gedlu E, Nega B, Tadesse BT, Chanie Y, Dawoud A, Moges FH, Bezabih A, Moges T, Centella T, Marianeschi S, Coca A, Collado R, Kassa MW, Johansson S, van Doorn C, Barber BJ, Teodori M. Factors associated with perioperative mortality in children and adolescents operated for tetralogy of Fallot: A sub-Saharan experience. J Card Surg. 2019;34(12):1478–85. https://doi.org/10.1111/jocs.14270 . Tchoumi JCT, Ambassa JC, Giamberti A, et al. Late surgical treatment of tetralogy of Fallot. Cardiovasc J Afr. 2011;22(4):179–81. Nadir Benbrik Bénédicte, Romefort LL, Golan et al. March. : Late repair of tetralogy of Fallot during childhood in patients from developing countries, European Journal of Cardio-Thoracic Surgery, Volume 47, Issue 3, 2015, Pages e113–e117. Waqar T, Riaz MU, Mahar T. Tetralogy of Fallot repair in patients presenting after Infancy: A single surgeon experience. Pak J Med Sci. 2017;33(4):984–7. Dixon LK, Dimagli A, Di Tommaso E, Sinha S, Fudulu DP, Sandhu M, Benedetto U, Angelini GD. Females have an increased risk of short-term mortality after cardiac surgery compared to males: Insights from a national database. J Card Surg. 2022;37(11):3507–19. https://doi.org/10.1111/jocs.16928 . S., K. T. S. T., M., L., S., R., & R.-K.R., C. (2006). Sex-related disparity in surgical mortality among pediatric patients. Congenit Heart Dis, 1(3), 77–88. http://ovidsp.ovid.com/ovidweb.cgi?T=JS &PAGE=reference&D=emed7&NEWS=N&AN=2006257860 Marelli A, Gauvreau K, Landzberg M, Jenkins K. (2010). Sex differences in mortality in children undergoing congenital heart disease surgery: A United States population-based study. Circulation, 122(11 SUPPL. 1), 234–240. https://doi.org/10.1161/CIRCULATIONAHA.109.928325 . LEACHMAN RD, HALLMAN, G. L., COOLEY DA. Relationship Between Polycythemia and Surgical Mortality in Patients Undergoing Total Correction for Tetralogy of Fallot. Circulation. 1965;32(July):65–8. https://doi.org/10.1161/01.CIR.32.1.65 . Ergün S, Genç SB, Yildiz O, Öztürk E, Güneş M, Onan IS, Güzeltaş A, Haydin S. Predictors of a complicated course after surgical repair of tetralogy of Fallot. Turkish J Thorac Cardiovasc Surg. 2020;28(2):264–73. https://doi.org/10.5606/tgkdc.dergisi.2020.18829 . Faerber JA, Huang J, Zhang X, Song L, DeCost G, Mascio CE, Ravishankar C, O’Byrne ML, Naim MY, Kawut SM, Goldmuntz E, Mercer-Rosa L. Identifying Risk Factors for Complicated Postoperative Course in Tetralogy of Fallot Using a Machine Learning Approach. Front Cardiovasc Med. 2021;8(July):1–10. https://doi.org/10.3389/fcvm.2021.685855 . Al Habib HF, Jacobs JF, Mavroudis C, Tchervenkov CI, O’Brien SM, Mohammadi S, et al. Contemporary patterns of management of Tetralogy of Fallot: data from the Society of Thoracic Surgeons Database. Ann Thorac Surg. 2010;90:813–20. Kirklin JK, Kirklin JW, Blackstone EH, Milano A. Pacifi- co AD. Effect of transannular patching on outcome after repair of tetralogy of Fallot. Ann Thorac Surg. 1989;48(6):783–91. Naghib S, van der Starre C, Gischler SJ, Joosten KF, Tibboel D. Mortality in very long-stay pediatric intensive care unit patients and incidence of withdrawal of treatment. Intensive Care Med. 2010;36(01):131–6. UNICEF. Tanzania Profile of Preterm and Low Birth Weight Prevention and Care. 2015;10–2.]. World Health Organization. WHO child growth standards: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: methods and development. World Health Organization; 2006. Harris 1PA, Taylor R, Thielke R, Payne J, Gonzalez N, Conde JG. Research electronic data capture (REDCap) – A metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inf. 2009;42(2):377–81. Harris 2PA, Taylor R, Minor BL, Elliott V, Fernandez M, O’Neal L, McLeod L, Delacqua G, Delacqua F, Kirby J, Duda SN, REDCap Consortium. The REDCap consortium: Building an international community of software partners. J Biomed Inf. 2019 May;9. 10.1016/j.jbi.2019.103208] . Hickey PA, Connor JA, Cherian KM, et al. International quality improvement initiatives. Cardiol Young. 2017;27(S6):S61–8. 10.1017/S1047951117002633 . Liu Y, Chen S, Zühlke L, Babu-Narayan SV, Black GC, Choy MK, Li N, Keavney BD. Global prevalence of congenital heart disease in school-age children: a meta-analysis and systematic review. BMC Cardiovasc Disord. 2020;20:1–0. Additional Declarations No competing interests reported. Supplementary Files SupplementarymaterialTOFversion5.docx Cite Share Download PDF Status: Published Journal Publication published 14 Sep, 2024 Read the published version in BMC Cardiovascular Disorders → Version 1 posted Editorial decision: Revision requested 03 Jul, 2024 Reviews received at journal 26 Jun, 2024 Reviews received at journal 21 Jun, 2024 Reviews received at journal 13 Jun, 2024 Reviewers agreed at journal 04 Jun, 2024 Reviewers agreed at journal 31 May, 2024 Reviewers agreed at journal 31 May, 2024 Reviewers agreed at journal 31 May, 2024 Reviewers invited by journal 31 May, 2024 Editor invited by journal 30 May, 2024 Editor assigned by journal 30 May, 2024 Submission checks completed at journal 22 May, 2024 First submitted to journal 15 May, 2024 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4422562","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":309249665,"identity":"275ed3d4-8076-4dc6-a911-58a9470a448f","order_by":0,"name":"Naizihijwa Majani","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAtklEQVRIiWNgGAWjYFACxgbmv/9sGBgkSNHCwMOWRpIWIOBhO0yCFnP2w80fJHjOJ/bPbj74gKHGJpqgFsuexAYDA4nbiTPuHEs2YDiWlttASIvBgcSGhASD24kNN3LMJBgbDhOh5fzDhgMHEs4lzidey43ExkagpsQNJGh52MzM2JBsvPFGWrJBAlF+OZ/++DNjg53svBvJBx98qLEhrAUGHMEqE4hVDgL2pCgeBaNgFIyCEQYATTVEk/Acm54AAAAASUVORK5CYII=","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":true,"prefix":"","firstName":"Naizihijwa","middleName":"","lastName":"Majani","suffix":""},{"id":309249666,"identity":"8d6640c5-80c7-4f84-9f1a-22766dc43d28","order_by":1,"name":"Godwin Sharau","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Godwin","middleName":"","lastName":"Sharau","suffix":""},{"id":309249667,"identity":"2ea35428-8cd2-4283-8042-a00fe37d0078","order_by":2,"name":"Vivienne Mlawi","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Vivienne","middleName":"","lastName":"Mlawi","suffix":""},{"id":309249668,"identity":"b51bd0ff-dd62-463a-9fac-0917b616f9ac","order_by":3,"name":"Zawadi Kalezi","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Zawadi","middleName":"","lastName":"Kalezi","suffix":""},{"id":309249669,"identity":"1e3f7e41-051c-4975-a23b-01e5e2802b5e","order_by":4,"name":"Stella Mongella","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Stella","middleName":"","lastName":"Mongella","suffix":""},{"id":309249670,"identity":"4190bc61-9b66-4da4-9487-60f734ae41e7","order_by":5,"name":"Nuru Letara","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Nuru","middleName":"","lastName":"Letara","suffix":""},{"id":309249671,"identity":"aae5bbe0-c15c-47ef-ae0b-35bc8ad4637f","order_by":6,"name":"Deogratias Nkya","email":"","orcid":"","institution":"Muhimbili University of Health and Allied Sciences","correspondingAuthor":false,"prefix":"","firstName":"Deogratias","middleName":"","lastName":"Nkya","suffix":""},{"id":309249672,"identity":"d2feff56-8d5d-466d-8ee9-019def4e4371","order_by":7,"name":"Sulende Kubhoja","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Sulende","middleName":"","lastName":"Kubhoja","suffix":""},{"id":309249673,"identity":"9e522e01-0973-43ec-b589-5367e5671452","order_by":8,"name":"Pilly Chillo","email":"","orcid":"","institution":"Muhimbili University of Health and Allied Sciences","correspondingAuthor":false,"prefix":"","firstName":"Pilly","middleName":"","lastName":"Chillo","suffix":""},{"id":309249674,"identity":"2166a114-2c93-4375-850d-6806ec0169e8","order_by":9,"name":"Martijn Slieker","email":"","orcid":"","institution":"Wilhelmina Children’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Martijn","middleName":"","lastName":"Slieker","suffix":""},{"id":309249675,"identity":"bfd6ed78-69ff-4cbf-ad76-d97c308fed75","order_by":10,"name":"Diederick Grobbee","email":"","orcid":"","institution":"Julius Global Health, Julius Center for Health Sciences and Primary Care, Utrecht University","correspondingAuthor":false,"prefix":"","firstName":"Diederick","middleName":"","lastName":"Grobbee","suffix":""},{"id":309249676,"identity":"35eaf9d8-0ea9-48b3-aa61-56b695b8354f","order_by":11,"name":"Janabi Mohammed","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Janabi","middleName":"","lastName":"Mohammed","suffix":""},{"id":309249677,"identity":"1e745dcc-5861-407e-a1e2-de4fe475428c","order_by":12,"name":"Peter Kisenge","email":"","orcid":"","institution":"Jakaya Kiwete Cardiac Institute","correspondingAuthor":false,"prefix":"","firstName":"Peter","middleName":"","lastName":"Kisenge","suffix":""}],"badges":[],"createdAt":"2024-05-15 04:53:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4422562/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4422562/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12872-024-04183-5","type":"published","date":"2024-09-14T15:57:22+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":64619040,"identity":"a0d5b53f-92fd-4d1f-b86d-cecff4438edc","added_by":"auto","created_at":"2024-09-16 16:10:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":958768,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4422562/v1/83fa4650-f78c-4de2-8a0b-e5ad3a91d738.pdf"},{"id":57722824,"identity":"c18c8950-a2d3-4dc2-8cfc-9c1923d2af63","added_by":"auto","created_at":"2024-06-04 19:12:20","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":25893,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementarymaterialTOFversion5.docx","url":"https://assets-eu.researchsquare.com/files/rs-4422562/v1/98fdd9e5da4b1c3e81c46116.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eSurgical Outcome for Tetralogy of Fallot in an African Setting; a Tanzanian Experience Using Retrospective Analysis of Hospital Data\u003c/p\u003e","fulltext":[{"header":"Highlights","content":"\u003cp\u003eThis study examined the clinical characteristics and 30-day surgical outcomes of patients with Tetralogy of Fallot who were treated in a low-middle-income setting\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy Limitations:\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eSingle center retrospective study\u003c/li\u003e\n \u003cli\u003eLack of Echocardiography data to access TOF severity\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eStudy Strength:\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eAdequate sample size compared to available study in the literature looking at TOF repair in African settings, with most having sample size of less than 100 patients.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Introduction","content":"\u003cp\u003eTetralogy of Fallot (TOF) is the most frequent cyanotic cardiac condition. It occurs in 0.34 per 1,000 live births and accounts for 7\u0026ndash;10% of all congenital heart disease (CHD) [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The severity of TOF depends on the degree of right ventricular outflow tract (RVOT) obstruction and the anatomy of pulmonary vasculature [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSurgery is the definitive treatment of TOF [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The recommended age for surgical repair is now 3\u0026ndash;6 months, and best within the first year of life [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Most centers reserve neonatal surgery for infants with hypercyanotic spells or severe cyanosis [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Early surgery can help avoid complications, conclude experts [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe overall outcome of TOF repair in developed regions is good, and the mortality rate is less than 3% [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In High-Income country (HIC) settings, over 90% of operated children with TOF are below the age of one year [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, in most developing nations, a typical TOF patient will present past the recommended age of surgical repair [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Ngwezi and colleagues (2013) documented that they operated on only 32% of TOF patients in infancy in their series in South Africa [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. The reported operative mortality of late complete repair of TOF in children beyond infancy ranges from 6.9-to 15% [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. The perioperative outcome is determined by the patient's characteristics and the centre\u0026rsquo;s related factors, including but not limited to disease severity, age at operation, oxygen saturation level and presence of comorbidities. Data shows that repairing TOF in infancy results in fewer postoperative issues and shorter hospital stays [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDue to the scarcity of cardiac centers in low- and middle-income countries (LMIC), there is an increased number of unrepaired CHD, with Africa recording the highest burden of unrepaired CHD globally [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. The accumulation of unrepaired TOF in these settings poses a challenge, and careful case selection is imperative to ensure that patients who will maximally benefit get treated. Determining drivers of successful surgical outcomes in developing countries is therefore necessary.\u003c/p\u003e \u003cp\u003eThis study assesses the clinical characteristics and 30-day surgical outcomes of patients with TOF at JKCI in Dar es Salaam from 2019 to 2021. We hypothesize that due to the lack of systematic screening for CHD in Tanzania, most patient will be operated on late, and their outcome may be suboptimal. The study was approved by the Jakaya Kikwete Institutional review board with IRB number AB.123/196/01/H7, and we followed the ethical guidelines stated in the 1975 Declaration of Helsinki. As this was a retrospective study, the IRB granted a waiver for consent.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Setting\u003c/h2\u003e \u003cp\u003eThe Jakaya Kikwete Cardiac Institute, JKCI, is a specialized National Referral Hospital and the only public Institute treating children with CHD since 2015. Located In Eastern Africa, Tanzania, JKCI has a typical LMIC setting. The Institute's experience can help answer pertinent questions regarding TOF repair in the region. The center provides cardiac surgery for adults and children. Pediatric cardiac surgery was established in 2015 by the local team and with the support of regular visits from international teams. Over 80% of surgeries were performed by the local team at the time of this study. Between 2019 and 2021, approximately 1,794 children were diagnosed with CHD and seen in the outpatient department (OPD) for the first time, out of which 180 were diagnosed with TOF (local database). The centre performs about 200 surgeries on children annually (unpublished local database); however, the capacity is insufficient to treat and operate all children. Patient selection follows the Institute protocol after discussion in the interdisciplinary meeting. Depending on the stage and anatomical characteristics, patients with TOF can undergo complete or palliative repair with a Blalock Tausing (BT )shunt.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design\u003c/h2\u003e \u003cp\u003eThis retrospective study evaluated patient characteristics, postoperative morbidity and mortality of patients who underwent TOF repair at JKCI. The study also examined the risk factors associated with the operative outcomes.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStudy Sample\u003c/h2\u003e \u003cp\u003eWe included all patients diagnosed with TOF and who underwent surgery at JKCI between January 2019 and December 2021. Patients with pulmonary atresia, an absent pulmonary valve, or common atrioventricular canal defects were excluded from the study because these conditions have different disease progression and management.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eData Measurement\u003c/h2\u003e \u003cp\u003eIn 2019, JKCI joined the International Quality Improvement Collaborative for Congenital Heart Disease (IQIC). A structured questionnaire designed by IQIC was employed to systematically collect information [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. The study data was collected and managed using the REDCap (Research Electronic Data Capture) ver.16 hosted at JKCI [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Medical officers input the data into REDCap, under the supervision of Pediatric Cardiologists. Each user is assigned an individual user ID and password, with access tailored to their specific role. All children undergoing congenital heart surgery are enrolled upon admission, and case report forms 1\u0026ndash;5 are completed. (For examples of case report forms, please refer to Appendix D). Case report form 6 is filled out during the 30-day follow-up visit. The JKCI's IQIC database undergoes an annual check by the Boston University team to ensure quality assurance and validity. The data-capturing tool focuses on factors such as nutritional status, prematurity, age, surgical procedure, co-morbidities, and outcomes, including mortality and infections. Preoperative characteristics recorded in this study encompass hematocrit levels, oxygen saturation, weight, and age. The WHO weight-for-age charts categorise weight as either normal for age or underweight [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. We measured surgical outcomes based on death rates, ICU and hospital stays. We considered stays longer than three days in the ICU and longer than seven days in the hospital to be lengthy [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Postoperative complications include wound infection, sepsis, bleeding, and reoperation. Additionally, patients were assessed for the presence of major medical illnesses, such as diabetes, sickle cell disease, HIV/AIDS, and malaria. The presence of any of these conditions was duly noted. Monitoring was conducted to identify any cardiopulmonary bypass (CPB)-related events. Any event that resulted in a patient undergoing re-operation was classified as a CPB-related event. Patients who displayed signs and symptoms of blood infection or surgical site infection and either underwent bacteriological testing or required an extension of antibiotic usage were carefully observed and labelled as cases of sepsis. Patients with more than 80% of missing data were excluded from the study.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eData Analysis\u003c/h2\u003e \u003cp\u003eData was extracted from REDCap to SPSS and analyzed using Stata statistical software, version 17. Both descriptive and analytical techniques were employed. Frequencies and percentages were used to summarize categorical data. Continuous data are presented as the means with standard deviations and medians with interquartile ranges (25th, 75th). Contingency tables were used to present cross-tabulations between the dependent and the independent variables. Mean tests were performed using independent sample t-tests, while Mann-Whitney was used to test differences in medians between samples. We used the chi-square and Fisher\u0026rsquo;s exact tests (as appropriate) to assess the associations between categorical variables. If p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, the associations were considered significant. We used logistic regressions to determine factors related to mortality and lengths of stay. We considered factors with a p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.2 in multivariable models using logistic regressions. We calculated crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). We reported all variables in the model with p values\u0026thinsp;\u0026lt;\u0026thinsp;0.05 as factors for in-hospital mortality or length of hospital stay.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eBaseline characteristics of the operated TOF Patients\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the demographic characteristics of the patients. Between January 2019 and December 2021, the team operated on 428 children out of these 107 children (22.1%) had TOF and aged between 1 and 18 years, predominantly male 62.6%, and male to female ration of 1.7:1. The median age at operation was 3.0 years (IQR: 2\u0026ndash;6), with over half of patients (n\u0026thinsp;=\u0026thinsp;60; 56.1%) being in the age range of 1\u0026ndash;5 years and only 18.7% younger than one year of age. Over 90% of patients were underweight, and the mean BMI was 14.6\u0026thinsp;+\u0026thinsp;3.1 kg/m2. The prematurity rate in the entire cohort was low at 2% compared to the national average of 11% [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. There was no CPB-related event recorded. Open Chest and Surgical bleeding rates were 1.9% and 2.8%, respectively. Only 4.7% had genetic syndrome, and medical illness was recorded in 2.8%. Bacteria sepsis was more common than surgical site infection (5.6% vs 0.9%). The median preoperative oxygen saturation was 81% (72,93), and almost one-third of the patients had less than 75% oxygen saturation values. Over a third of patients had hematocrits greater than 55%, with a median hematocrit of 48.7% IQR (37.4, 69.0). Slightly more than a third of the patients who underwent surgery 36.4% required a transannular patch.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eImmediate surgical outcomes by the age of operation\u003c/h2\u003e \u003cp\u003eEleven patients died during the study period giving a mortality rate of 10.3%. All deaths occurred before discharge from the hospital, and there was no mortality in the group younger than the age of one year. The median ICU stay was 72 hours (48,120). On average, over two-thirds of patients stayed in hospital for more than seven days; the median days of hospital stay were 8.5 (7,11), Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eDifferences in clinical characteristics between early and late repair\u003c/h2\u003e \u003cp\u003eTwenty patients with TOF (18.7%), underwent surgery before the age of one year. Patients older than one year had higher hematocrits, with 50% having hematocrits greater than 55%. Older children were more cyanosed, with 31% having a saturation level less than 75% vs 20%; these differences were not statistically significant. The comorbidities were similar between TOF patients irrespective of age, except for a slight tendency toward lower hematocrit levels in those operated on after less than one year (Supplementary Appendix C).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eFactors associated with in-hospital mortality outcome for TOF patients\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e displays the baseline characteristics that were associated with in-hospital mortality. In the univariate analysis, some factors were found to have higher odds of in-hospital mortality, but none of these factors were statistically significant. These factors included female sex (OR\u0026thinsp;=\u0026thinsp;1.4 [0.45\u0026ndash;4.30]), genetic syndrome (OR\u0026thinsp;=\u0026thinsp;2.04 [0.32\u0026ndash;13.08]), saturation below 75% (OR\u0026thinsp;=\u0026thinsp;1.93 [0.635\u0026ndash;0.89]) and transannular patch use (OR\u0026thinsp;=\u0026thinsp;3.05 [0.95\u0026ndash;9.82]). Additionally, the odds of dying were 2.02 (odds ratio [OR] 2.02 [0.41\u0026ndash;9.97]) for children with hematocrit levels greater than 55%.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eFactors associated with length of hospital and ICU stay among operated TOF patients\u003c/h2\u003e \u003cp\u003eIt was observed that certain baseline characteristics were associated with a higher chance of longer hospital stays, but none of them were statistically significant. The characteristics that indicated higher odds were males (OR\u0026thinsp;=\u0026thinsp;1.33 [0.85\u0026ndash;2.10]), age younger than one year (OR\u0026thinsp;=\u0026thinsp;1.24 [0.76\u0026ndash;2.03]), underweight (OR\u0026thinsp;=\u0026thinsp;1.38 [0.60\u0026ndash;3.18]), hematocrit above 55% (OR\u0026thinsp;=\u0026thinsp;1.45 [0.95\u0026ndash;2.20]), and saturations below 75% (OR\u0026thinsp;=\u0026thinsp;1.16 [0.77\u0026ndash;1.74]). The use of TAP was found to increase the length of hospital stay by 1.25 times (0.84\u0026ndash;1.85). It is worth noting that all patients stayed in ICU for over 72 hours. (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\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\u003eBaseline clinical characteristics of children with TOF repair at the JKCI, N\u0026thinsp;=\u0026thinsp;107\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFrequency\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePercent\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMale\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e67\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e62.6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge at Surgery (years)\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMedian (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e3 (2, 6)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLess a year\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e20\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e18.7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u0026ndash;5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e60\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e56.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e6+\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e27\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e25.2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI\u003c/b\u003e\u003csup\u003e\u003cb\u003ea\u003c/b\u003e\u003c/sup\u003e \u003cb\u003eMean (SD)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e14.5 (3.1)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eUnderweight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e91\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e90.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eNormal weight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e8.9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOverweight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.0\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePrematurity\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.0\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGenetic Syndrome\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e4.7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMedical Illness\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCPB Related Event\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.0\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOpen Chest\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eInfection Bacterial Sepsis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e5.6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eInfection Surgical Site\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComplication Surgery for Bleeding\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHematocrits\u003c/b\u003e\u003csup\u003e\u003cb\u003ec\u003c/b\u003e\u003c/sup\u003e \u003cb\u003eMedian (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e48.7 (37.4, 59.0)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;55\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e60\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e63.8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSaturation Median (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e80 (72, 93)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;75%\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e32\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e30.2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eIQR-Interquartile Range, BMI-Body Mass IndexSD-Standard Deviation, CPB- Cardiopulmonary Bypass, SD\u0026thinsp;=\u0026thinsp;Standard deviation, TOF\u0026thinsp;=\u0026thinsp;Tetralogy of Fallot, kg\u0026thinsp;=\u0026thinsp;weight in kilograms\u003c/em\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 Outcomes among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N\u0026thinsp;=\u0026thinsp;107\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\u003eOutcome\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIn hospital mortality (n, %)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (10.3%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLength of ICU stay (\u0026gt;\u0026thinsp;72 hours)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e60 (98.4%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMedian length of ICU stays in hours (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e72 (48, 120)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLength of hospital days (7 days)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e70 (66.0%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMedian Length of hospital days (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e8.5 (7\u0026ndash;11)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eNote: Long ICU stay defined as more than 72hours and Long hospital stay as more than seven days. No Mortality occurred after hospital discharge.\u003c/em\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\u003eFactors associated with in-hospital mortality among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N\u0026thinsp;=\u0026thinsp;107\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=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFactor\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eNumber\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003en (%)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eIn hospital mortality\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003en (%)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eCrude OR (95%CI)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eAdjusted OR (95%CI)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSex\u003c/b\u003e (Female)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e40 (37.4)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e5 (12.5)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e1.40 (0.45\u0026ndash;4.30)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003e0.74 (0.25\u0026ndash;2.21)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge (years)\u003c/b\u003e\u0026thinsp;\u0026gt;\u0026thinsp;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e87 (92.5)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e11 (12.6)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI\u003c/b\u003e Underweight\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e98 (91.0)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e11 (9.9)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGenetic Syndrome( Yes)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e5 (4.7)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e1 (20)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003e2.04 (0.32\u0026ndash;13.08)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMedical Illness\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e3 (2.8)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e0 (0)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e104 (97.2)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e11 (10.6)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHematocrits\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e45 (44.7)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e2 (4.4)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e0.71 (0.14\u0026ndash;3.47)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSaturation\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;75%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003e33 (30.2)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e5 (15.1)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e1.93 (0.63\u0026ndash;5.89)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTransannular patch\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39 (36.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003e7 (18.0)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e3.05 (0.95\u0026ndash;9.82)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003e3.23 (0.95-11.0)\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\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\u003eFactors for length of hospital stay among patients who underwent surgery for TOF at the JKCI between 2019 and 2021, N\u0026thinsp;=\u0026thinsp;107\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" 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=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFactor\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eNumber\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003en (%)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eLength of hospital stay n (%)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eCrude OR (95%CI)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eAdjusted OR (95%CI)\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSex\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMale\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e64 (64.0)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e22 (73.3)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.33 (0.85\u0026ndash;2.10)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e1.25 (0.83\u0026ndash;1.87)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge (years)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e5 (5.0)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e4 (80.0)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.24 (0.76\u0026ndash;2.03)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e1.11 (0.67\u0026ndash;1.74)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eUnderweight\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e98 (87.5)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e29 (69.1)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.38 (0.60\u0026ndash;3.18)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHematocrit\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e\u0026gt;\u0026thinsp;50\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e42(40.4)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e12 (28.5)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.79 (0.52\u0026ndash;1.22)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.79 (0.51\u0026ndash;1.21)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSaturation\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e75+%\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e74 (71.5)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e24 (32.4)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.16 (0.77\u0026ndash;1.74)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTransannular patch\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eYes\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e36 (34.6)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e15 (41.6)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e1.25 (0.84\u0026ndash;1.85)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study focused on the surgical outcome of Tetralogy of Fallot patients from Tanzania. In this cohort, TOF accounts for nearly a quarter (22.1%) of all operated patients; highlighting the substantial burden of TOF in this setting. Although there is not much documentation on the burden of TOF in LMIC, experts estimate that it is consistent with the global prevalence, where TOF makes up 7\u0026ndash;10% of all CHD cases [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The excess proportion we see in our cohort may be for reasons of survival ship. Without surgery, 90% of children with CHD and TOF die within ten years, but 66% survive the first year of life [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. We speculate that due to a lack of systematic screening for CHD, the patients we encounter in our settings represent milder forms of the disease, the survivors, while more severe cases perish at a young age before receiving a diagnosis, underscoring the importance of early detection through screening programs.\u003c/p\u003e \u003cp\u003eOur cohort's median age at repair was three years. As anticipated, only 18.7% of patients who underwent TOF were younger than one year of age. In developed countries, in contrast, more than 90% of operations are conducted on patients younger than one year of age [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Age at repair is important. The Toronto group reported the safety of surgery between 3 and 11 months of age, while a risk of death was associated with surgery at 12\u0026thinsp;+\u0026thinsp;months [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Our study confirmed these findings, as no mortalities were observed before one year of age. Nevertheless, a later age for TOF repair is a common trend in most developing nations. In Iran, the mean age of operation for TOF patients was four years. In Brazil, a cohort of 83 TOF patients had a mean age at operation of 3.7 years. Similarly, Turkey's mean age at operation was 2.3 years [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, and \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Insufficient screening and access to echocardiography in rural health canters of developing countries act as barriers to early detection and treatment.\u003c/p\u003e \u003cp\u003eEarly repair is crucial as it can alleviate the effects of cyanosis and protect vital organs. Additionally, early repair prevents the obstruction of the right ventricular outflow tract (RVOT) caused by fibrosis, a risk factor for poor outcomes [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Consequently, patients in LMICs who undergo surgery at a later stage due to delayed presentation are more likely to experience unfavorable outcomes.\u003c/p\u003e \u003cp\u003eIn our cohort, the mortality rate for TOF patients was 10.3%, and all fatalities occurred within the hospital. This is consistent with the reported mortality rates of 6.9\u0026ndash;15% in developing countries [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. For instance, in Ethiopia, a study involving 62 TOF patients operated between 2009 and 2014 reported a mortality rate of 12.9% [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Tchoumi et al. studied 22 TOF patients who underwent complete repair surgery by a visiting team. The average age of the patients was 9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;6.5 years, and the mortality rate was 9% [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Similarly, in a study by Benbrik et al., complete repair of TOF was performed on 47 children from developing countries at a mean age of 4.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2 years, with a postoperative mortality rate of 4.2% [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, an interesting contrast can be seen in Pakistan, where Waqar et al. reported on a large cohort of 307 children who underwent TOF repair at a mean age of 9.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9 years. The 30-day mortality rate in that study was 1.3%, similar to rates reported in developed nations [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. In Europe and North America, perioperative mortality for TOF is less than 3% due to improved management strategies [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The outcomes observed in various developing countries can partially be attributed to the experience and expertise of the healthcare centers and systemic factors outside the disease that contribute to higher mortality rates [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. This was demonstrated in a cohort of 47 African patients who were operated on in France, which exhibited a low mortality rate of 3.2%, comparable to that of local patients, despite being older than the 90 French patients [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Therefore, as emerging centers in low- and middle-income countries gain more experience and handle larger patient volumes, we expect improved outcomes over time.\u003c/p\u003e \u003cp\u003eAlthough Tetralogy of Fallot is more common in males according to the literature and was shown in our data set to be 62.6%, female sex in our cohort was associated with 40% higher hospital mortality. We are unaware of any reports indicating higher mortality rates for females following TOF repair. However, historical reports have indicated that females are at a high risk of death postcardiac surgery [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Chang and Klitzner were the first to show sex differences in-hospital mortality in children undergoing cardiac CHD surgery; using data from 1989 to 1999 in California, in their study, the female sex was associated with an 18% greater risk of death [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. A US population study examining sex differences in CHD surgical outcomes showed that female in-hospital mortality was 21% greater [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The cause of excess mortality in females is unclear [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSurgical mortality is influenced by the severity of the disease. In the case of patients with Tetralogy of Fallot (TOF) who experience deep cyanosis and higher hematocrit levels, their condition is more critical. In our study, we found that children with hematocrit levels exceeding 55% and a haemoglobin saturation below 75% was at a higher risk of mortality and experienced longer stays in the ICU and hospital. A study conducted in Houston, Texas, between 1954 and 1962, involving 203 patients with TOF, demonstrated that a high hematocrit was a reliable risk indicator. Patients with a hematocrit greater than 55% had a mortality rate of 31%, while those below 55% had a mortality rate of 10% [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Furthermore, a Turkish study revealed a connection between higher hematocrit levels and unfavorable outcomes, including extended hospital stays, prolonged mechanical ventilation, prolonged ICU stays, and increased occurrence of major adverse effects [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. In Houston, a successful approach to reducing mortality in TOF surgeries involved using a Blalock-Taussig (BT) shunt to lower hemoglobin concentration from above 18 gm to below 18 gm [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRecent studies utilizing machine learning to assess perioperative predictors of TOF outcomes have suggested that preserving right ventricular remodeling and optimizing hematocrit levels are effective strategies [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Therefore, for patients presenting late with deep cyanosis and high hematocrit levels in low- and middle-income countries (LMICs) who undergo palliation and delayed surgery, the use of a BT shunt could be a preferable strategy [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe need for trans-annular patches (TAPs) for TOF repairs can indicate disease severity and technical difficulties, resulting in longer bypass times and ICU and hospital stay [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. In our series, TAP patients were three times more likely to experience fatal outcomes. These findings are consistent with many studies in the literature. Surgeons in North America frequently use ventriculotomy and TAP for TOF repair [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. In Europe, TAP techniques were associated with increased mortality [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Notably, although desirable, valve-sparing is not achievable in most settings [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Therefore, teams must understand the risks of TOF patients receiving TAP to provide optimal care.\u003c/p\u003e \u003cp\u003eLastly, TOF patients had slightly different characteristics than others who underwent congenital surgery at the Centre during the same period. TOF patients had higher average weight values and experienced more postsurgical bleeding and sepsis but also had increased levels of cyanosis and hematocrit (supplementary material appendix A and B). Understandably, these differences are due to the complexities associated with the TOF condition. Comparably, however, all patients treated at the same cardiac institute were late presenters. These findings, in general, indicate that there is still room for improvement in the management of CHD and particularly TOF. Nonetheless, they also highlight the resilience and dedication of patients and medical professionals in the face of challenging circumstances.\u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eSummary\u003c/h2\u003e \u003cp\u003eOur data set highlights the importance of early detection for CHD. By implementing a systematic screening process for CHD, including TOF, more severe cases can be identified and diagnosed earlier. Additionally, recognizing the risk factors associated with TOF and implementing strategies like bridging repair with a BT shunt and systematic screening processes for CHD may contribute to excellent outcomes, reduced mortality, shorter ICU and hospital stays, and improved survival rates for individuals with TOF in LMIC.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eTo the best of our knowledge, this study represents the first examination of factors related to mortality in Tanzania, specifically for the total correction of TOF. However, it is important to acknowledge that this study is based on a single centre, potentially limiting its findings' generalizability to other settings. Nevertheless, the results hold significance since the Jakaya Kikwete Cardiac Institute (JKCI) currently stands as the sole center providing cardiac care for children in the country.\u003c/p\u003e \u003cp\u003eOne limitation of this study is the unavailability of echocardiography data, which rendered the classification of TOF severity impossible. Consequently, the researchers resorted to using TAP (Trans Annular Patch) as a means to indicate severe TOF. Moreover, this investigation did not account for additional influential factors such as surgical expertise or intensive care unit (ICU) experience, which could potentially impact outcomes. Notwithstanding these limitations, the study offers valuable insights into the prevailing circumstances faced by TOF patients at the National Referral Center while identifying immediate factors clinicians within this facility can utilize to enhance outcomes. However, it is crucial to recognize that this study underscores the necessity for a prospective study, encompassing a comprehensive analysis of all factors associated with outcomes, to gain a deeper understanding of this commonly occurring CHD within the Tanzanian context.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eRepair of TOF in African settings is characterized by older age and poor nutritional status during surgery, leading to high perioperative mortality and morbidity. This study underscores the importance of addressing these issues to improve the surgical outcomes of TOF repairs in resource-limited regions.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Jakaya Kikwete Institutional Review Board reviewed and approved the study, with Institutional review board number AB.123/196/01/H7. The Jakaya Kikwete Institutional review board waived the need for informed consent because of the study\u0026apos;s retrospective nature.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone to declare\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere was no funding for this study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors will make the raw data supporting the conclusions of this article available without undue reservation, upon reasonable request to the first Author Naizihijwa Majani.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNM contributed to the conception and design of the study. GS, VM, SM, NL, DN, and SK collected data and organized the database. NM performed the statistical analysis\u0026nbsp;together with ZK. NM, MS, and PC were involved in the study and\u0026nbsp;interpretation of the\u0026nbsp;data. MJ, DG, and PK supervised the study. NM wrote the first draft of the manuscript. All\u0026nbsp;the\u0026nbsp;authors reviewed and edited all\u0026nbsp;the\u0026nbsp;manuscript sections and read and approved the submitted version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank the Department of Pediatric Cardiac Surgery, the Division of Pediatric Cardiology, and\u0026nbsp;the\u0026nbsp;Pediatric ICU for their unwavering care\u0026nbsp;of\u0026nbsp;children with\u0026nbsp;congenital heart disease\u0026nbsp;despite limited resources. We also acknowledge Winnie Msakyusa and Jackline Oseti for contributing\u0026nbsp;to data entry in\u0026nbsp;the surgical database.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBailliard F, Anderson RH. Tetralogy of Fallot. Orphanet J Rare Dis. 2009;4:2. Published 2009 Jan 13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVan der Ven JPG, van den Bosch E, Bogers AJCC, Helbing WA. Current outcomes and treatment of tetralogy of Fallot. F1000Res. 2019;8: F1000 Faculty Rev-1530. Published 2019 Aug 29.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMouws EMJP, de Groot NMS, van de Woestijne PC, de Jong PL, Helbing WA, van Beynum IM, Bogers AJJC. Tetralogy of Fallot in the Current Era. Semin Thorac Cardiovasc Surg. 2019;31(3):496\u0026ndash;504. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1053/j.semtcvs.2018.10.015\u003c/span\u003e\u003cspan address=\"10.1053/j.semtcvs.2018.10.015\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLoomba RS, Buelow MW, Woods RK. Complete Repair of Tetralogy of Fallot in the Neonatal Versus Nonneonatal Period: A Meta-analysis. Pediatr Cardiol. 2017;38(5):893\u0026ndash;901.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eValente AM, Gauvreau K, Assenza GE, et al. Contemporary predictors of death and sustained ventricular tachycardia in patients with repaired tetralogy of Fallot enrolled in the INDICATOR cohort. Heart. 2014;100(3):247\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003evan der Ven JPG, van den Bosch E, Bogers AJCC, Helbing WA. (2019). Current outcomes and treatment of tetralogy of fallot [version 1; peer review: 2 approved]. \u003cem\u003eF1000Research\u003c/em\u003e, \u003cem\u003e8\u003c/em\u003e, 1\u0026ndash;15. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.12688/f1000research.17174.1\u003c/span\u003e\u003cspan address=\"10.12688/f1000research.17174.1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSandoval N, Carre\u0026ntilde;o M, Novick WM, Agarwal R, Ahmed I, Balachandran R, Balestrini M, Cherian KM, Croti U, Du X, Gauvreau K, Cam Giang DT, Shastri R, Jenkins KJ. Tetralogy of Fallot Repair in Developing Countries: International Quality Improvement Collaborative. Ann Thorac Surg. 2018;106(5):1446\u0026ndash;51. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.athoracsur.2018.05.080\u003c/span\u003e\u003cspan address=\"10.1016/j.athoracsur.2018.05.080\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNgwezi DP, Vanderdonck K, Levin SE, Cilliers A. An audit of surgical repair of Tetralogy of Fallot in an African tertiary care center. SA Heart. 2013;10(3):520\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJuliana J, Sembiring YE, Rahman MA, Soebroto H. Mortality Risk Factors in Tetralogy of Fallot Patients Undergoing Total Correction. Folia Med Indonesiana. 2021;57(2):151. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.20473/fmi.v57i2.22107\u003c/span\u003e\u003cspan address=\"10.20473/fmi.v57i2.22107\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaygi M, Ergul Y, Tola HT, et al. Factors affecting perioperative mortality in tetralogy of Fallot. Pediatr Int. 2015;57(5):832\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGerling C, Rukosujew A, Kehl. Do the Age of Patients with Tetralogy of Fallot at the Time of Surgery and the Applied Surgical Technique Influence the Reoperation Rate? Herz. 2009;34:155\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBertranou EG, Blackstone EH, Hazelrig JB, Turner ME, Kirklin JW. (1978). Life expectancy without surgery in tetralogy of Fallot. \u003cem\u003eAm. J. Cardiol\u003c/em\u003e. 42 (3): 458\u0026ndash;66. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/0002-9149(78)90941-4\u003c/span\u003e\u003cspan address=\"10.1016/0002-9149(78)90941-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID 685856. Hashemzadeh K, Hashemzadeh S (2010). Early and late results of total correction of tetralogy of Fallot. Acta Med Iranica 48, 117- 122.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVan Dongen EI, Glansdorp AG, Mildner RJ, McCrindle BW, Sakopoulos AG, VanArsdell G, Williams WG, Bohn D. The influence of perioperative factors on outcomes in children aged less than 18 months after repair of tetralogy of Fallot. J Thorac Cardiovasc Surg. 2003;126(3):703\u0026ndash;10. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/S0022-5223(03)00035-7\u003c/span\u003e\u003cspan address=\"10.1016/S0022-5223(03)00035-7\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSarris GE, Coma\u0026thinsp;+\u0026thinsp;s JV, Toyota Z, et al. Results of reparative surgery for tetralogy of Fallot: data from the European Association for Cardio-Thoracic Surgery Congenital Database. Eur J Cardiothorac Surg. 2012;42(5):766\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAzari A, Nezafati MH, Bigdelu L. Early post operative mortality of Total Correction of Tetralogy of Fallot. J Cardio-Thoracic Med. 2017;5(4):222\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePinheiro P, de Azevedo S, V. M. P., Rocha G. Predicting Factors of Surgical Mortality in Children and Adolescents Undergoing Correction of Tetralogy of Fallot. Int J Cardiovasc Sci. 2023;36:1\u0026ndash;11. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.36660/ijcs.20200394\u003c/span\u003e\u003cspan address=\"10.36660/ijcs.20200394\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaygi M, Ergul Y, Tola HT, Ozyilmaz I, Ozturk E, Onan IS, Haydin S, Erek E, Yeniterzi M, Guzeltas A, Odemis E, Bakir I. Factors affecting perioperative mortality in tetralogy of Fallot. Pediatr Int. 2015;57(5):832\u0026ndash;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/ped.12627\u003c/span\u003e\u003cspan address=\"10.1111/ped.12627\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHashemzadeh K, Hashemzadeh S. Early and late results of total correction of tetralogy of fallot. Acta Medica Iranica. 2010;48(2):117\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTefera E, Gedlu E, Nega B, Tadesse BT, Chanie Y, Dawoud A, Moges FH, Bezabih A, Moges T, Centella T, Marianeschi S, Coca A, Collado R, Kassa MW, Johansson S, van Doorn C, Barber BJ, Teodori M. Factors associated with perioperative mortality in children and adolescents operated for tetralogy of Fallot: A sub-Saharan experience. J Card Surg. 2019;34(12):1478\u0026ndash;85. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/jocs.14270\u003c/span\u003e\u003cspan address=\"10.1111/jocs.14270\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTchoumi JCT, Ambassa JC, Giamberti A, et al. Late surgical treatment of tetralogy of Fallot. Cardiovasc J Afr. 2011;22(4):179\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNadir Benbrik B\u0026eacute;n\u0026eacute;dicte, Romefort LL, Golan et al. March. : Late repair of tetralogy of Fallot during childhood in patients from developing countries, European Journal of Cardio-Thoracic Surgery, Volume 47, Issue 3, 2015, Pages e113\u0026ndash;e117.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWaqar T, Riaz MU, Mahar T. Tetralogy of Fallot repair in patients presenting after Infancy: A single surgeon experience. Pak J Med Sci. 2017;33(4):984\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDixon LK, Dimagli A, Di Tommaso E, Sinha S, Fudulu DP, Sandhu M, Benedetto U, Angelini GD. Females have an increased risk of short-term mortality after cardiac surgery compared to males: Insights from a national database. J Card Surg. 2022;37(11):3507\u0026ndash;19. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1111/jocs.16928\u003c/span\u003e\u003cspan address=\"10.1111/jocs.16928\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eS., K. T. S. T., M., L., S., R., \u0026amp; R.-K.R., C. (2006). Sex-related disparity in surgical mortality among pediatric patients. Congenit Heart Dis, 1(3), 77\u0026ndash;88. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://ovidsp.ovid.com/ovidweb.cgi?T=JS\u003c/span\u003e\u003cspan address=\"http://ovidsp.ovid.com/ovidweb.cgi?T=JS\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u0026amp;PAGE=reference\u0026amp;D=emed7\u0026amp;NEWS=N\u0026amp;AN=2006257860\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMarelli A, Gauvreau K, Landzberg M, Jenkins K. (2010). Sex differences in mortality in children undergoing congenital heart disease surgery: A United States population-based study. Circulation, 122(11 SUPPL. 1), 234\u0026ndash;240. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1161/CIRCULATIONAHA.109.928325\u003c/span\u003e\u003cspan address=\"10.1161/CIRCULATIONAHA.109.928325\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLEACHMAN RD, HALLMAN, G. L., COOLEY DA. Relationship Between Polycythemia and Surgical Mortality in Patients Undergoing Total Correction for Tetralogy of Fallot. Circulation. 1965;32(July):65\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1161/01.CIR.32.1.65\u003c/span\u003e\u003cspan address=\"10.1161/01.CIR.32.1.65\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eErg\u0026uuml;n S, Gen\u0026ccedil; SB, Yildiz O, \u0026Ouml;zt\u0026uuml;rk E, G\u0026uuml;neş M, Onan IS, G\u0026uuml;zeltaş A, Haydin S. Predictors of a complicated course after surgical repair of tetralogy of Fallot. Turkish J Thorac Cardiovasc Surg. 2020;28(2):264\u0026ndash;73. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.5606/tgkdc.dergisi.2020.18829\u003c/span\u003e\u003cspan address=\"10.5606/tgkdc.dergisi.2020.18829\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFaerber JA, Huang J, Zhang X, Song L, DeCost G, Mascio CE, Ravishankar C, O\u0026rsquo;Byrne ML, Naim MY, Kawut SM, Goldmuntz E, Mercer-Rosa L. Identifying Risk Factors for Complicated Postoperative Course in Tetralogy of Fallot Using a Machine Learning Approach. Front Cardiovasc Med. 2021;8(July):1\u0026ndash;10. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3389/fcvm.2021.685855\u003c/span\u003e\u003cspan address=\"10.3389/fcvm.2021.685855\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAl Habib HF, Jacobs JF, Mavroudis C, Tchervenkov CI, O\u0026rsquo;Brien SM, Mohammadi S, et al. Contemporary patterns of management of Tetralogy of Fallot: data from the Society of Thoracic Surgeons Database. Ann Thorac Surg. 2010;90:813\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKirklin JK, Kirklin JW, Blackstone EH, Milano A. Pacifi- co AD. Effect of transannular patching on outcome after repair of tetralogy of Fallot. Ann Thorac Surg. 1989;48(6):783\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNaghib S, van der Starre C, Gischler SJ, Joosten KF, Tibboel D. Mortality in very long-stay pediatric intensive care unit patients and incidence of withdrawal of treatment. Intensive Care Med. 2010;36(01):131\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUNICEF. Tanzania Profile of Preterm and Low Birth Weight Prevention and Care. 2015;10\u0026ndash;2.].\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWorld Health Organization. WHO child growth standards: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: methods and development. World Health Organization; 2006.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHarris 1PA, Taylor R, Thielke R, Payne J, Gonzalez N, Conde JG. Research electronic data capture (REDCap) \u0026ndash; A metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inf. 2009;42(2):377\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHarris 2PA, Taylor R, Minor BL, Elliott V, Fernandez M, O\u0026rsquo;Neal L, McLeod L, Delacqua G, Delacqua F, Kirby J, Duda SN, REDCap Consortium. The REDCap consortium: Building an international community of software partners. J Biomed Inf. 2019 May;9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.jbi.2019.103208]\u003c/span\u003e\u003cspan address=\"10.1016/j.jbi.2019.103208]\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHickey PA, Connor JA, Cherian KM, et al. International quality improvement initiatives. Cardiol Young. 2017;27(S6):S61\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1017/S1047951117002633\u003c/span\u003e\u003cspan address=\"10.1017/S1047951117002633\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu Y, Chen S, Z\u0026uuml;hlke L, Babu-Narayan SV, Black GC, Choy MK, Li N, Keavney BD. Global prevalence of congenital heart disease in school-age children: a meta-analysis and systematic review. BMC Cardiovasc Disord. 2020;20:1\u0026ndash;0.\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":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Tetralogy of Fallot, Surgical outcomes, Low-middle-income setting","lastPublishedDoi":"10.21203/rs.3.rs-4422562/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4422562/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Tetralogy of Fallot (TOF) is typically treated in infancy but often done late in many resource-limited countries, jeopardizing surgical outcomes. This study examined the results of TOF repair surgery at the Jakaya Kikwete Cardiac Institute (JKCI) in Tanzania, an emerging cardiac centre in Eastern Africa.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA retrospective cohort study of children \u0026lt;18 years with TOF post-surgical repair between 2019 and 2021 was conducted. Data on socio-demography, pre-and postoperative cardiac complications, Intensive Care Unit (ICU) and hospital stay, and in-hospital and 30-day mortality were analyzed. Logistic regressions were employed to find the factors for mortality, ICU, and hospital stays.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The I07 children operated on were majority male (62.3%), with a median age of 3.0 years (IQR: 2- 6). Almost all (90%) were underweight, with a mean BMI of 14.6 \u003cu\u003e+ 3.1 \u003c/u\u003ekg/m\u003csup\u003e2\u003c/sup\u003e. Only 18.7% were below one year of age. Haematocrits were high, with a median of 48.7 (IQR: 37.4-59.0). Bacterial sepsis was more common than surgical site infection (5.6% vs 0.9%). The median oxygen saturation was 81% (IQR:72-93). The median ICU stay was 72 hours (IQR:48-120), with ICU duration exceeding three days for most patients. The median hospital stay was 8.5 days (IQR:7-11), with 66% experiencing an extended hospital stay of \u0026gt; 7 days. The in-hospital mortality rate was 10.3%, with no deaths occurring in children less than one year of age nor after discharge during the 30-day follow-up period. No statistically significant differences were observed in outcomes in relation to clinical and demographic characteristics.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e TOF repairs in an African setting face challenges associated with patients' older age and compromised nutritional status during the surgery. Perioperative mortality rates and morbidity for patients operated at an older age remain elevated. It’s important to address these issues to improve outcomes in these settings.\u003c/p\u003e","manuscriptTitle":"Surgical Outcome for Tetralogy of Fallot in an African Setting; a Tanzanian Experience Using Retrospective Analysis of Hospital Data","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-04 19:12:08","doi":"10.21203/rs.3.rs-4422562/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-07-03T06:59:40+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-26T06:40:03+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-22T03:33:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-13T14:58:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"178032288709818132433731280063847398116","date":"2024-06-04T17:28:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"20861730647142573206254789363677253304","date":"2024-05-31T21:19:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"80398967737953640770018497318571523640","date":"2024-05-31T09:02:14+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"191089781869560866068482319154119544333","date":"2024-05-31T06:57:52+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-05-31T05:56:11+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-05-30T13:17:55+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-05-30T12:46:43+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-05-22T09:20:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cardiovascular Disorders","date":"2024-05-15T04:49:57+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ad0dbfb5-fb25-4b99-ab60-b5b041132f1c","owner":[],"postedDate":"June 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-09-16T16:01:22+00:00","versionOfRecord":{"articleIdentity":"rs-4422562","link":"https://doi.org/10.1186/s12872-024-04183-5","journal":{"identity":"bmc-cardiovascular-disorders","isVorOnly":false,"title":"BMC Cardiovascular Disorders"},"publishedOn":"2024-09-14 15:57:22","publishedOnDateReadable":"September 14th, 2024"},"versionCreatedAt":"2024-06-04 19:12:08","video":"","vorDoi":"10.1186/s12872-024-04183-5","vorDoiUrl":"https://doi.org/10.1186/s12872-024-04183-5","workflowStages":[]},"version":"v1","identity":"rs-4422562","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4422562","identity":"rs-4422562","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}