Case Report: A Rare Presentation of Posterior Left Ventricular Branch Block Associated With Syncope

Case Report: A Rare Presentation of Posterior Left Ventricular Branch Block Associated With Syncope | 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 Case Report Case Report: A Rare Presentation of Posterior Left Ventricular Branch Block Associated With Syncope Ammara Waheed Arain, Imran Sandeelo, Anushka Andani, Amna Qazi, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6589779/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Syncope characterized by self-limited transient loss of consciousness , affecting 19% of population remains diagnostically challenging with 10% cases unexplained. Rarely syncope links to posterior left ventricular branch block, a less reported phenomenon, highlighting need for improved diagnostic approaches. Case A 59 year old hypertensive male, presented with syncope with initial normal examinations. Elevated Troponin I levels and subsequent tests revealed AV dissociation and significant coronary artery stenosis, notably in left circumflex and posterior left ventricular branches. This led to a complete PCI targeting the left circumflex artery and plain old balloon angioplasty (POBA) to posterior left ventricular branch followed by temporary pacemaker placement. Post intervention, the patient remained stable with no occurence of syncope and normal 24 hour ambulatory ECG monitoring. Discussion Isolated posterior left ventricular (PLV) branch block is a rarely- discussed topic in medical literature. This article primarily aims to review existing studies and present a detailed case study, shedding light on this rare phenomenon. Posterior left ventricular branch block Syncope PCI POBA Temporary pacemaker Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Background Syncope is a clinical problem with a prevalence of 19% in the general population[ 1 ]. Despite advancements in recent years, the reason for 10% of cases remains unknown[ 2 ]. Although cardiac reasons continue to be a major factor, the very uncommon correlation between posterior left ventricular branch block and syncope is worth mentioning. Single-vessel coronary artery disease is defined as stenosis of at least 70% or more of one major coronary artery, i.e the Left Circumflex or Right coronary artery, Left Anterior Descending or any of their respective branch i.e Obtuse, Posterior left ventricular artery, Posterior Descending Artery or Diagonal artery[ 3 ] is acknowledged for its broad spectrum of clinical manifestations. However, there is few data linking it to syncope, particularly regarding the involvement of the posterior left ventricular branch. Awareness of this unusual presentation allows the recording of rare clinical situations and helps cardiologists improve diagnostic methods that may encounter similar cases in their general clinical practice. Here we describe the management of a patient with the distal circumflex branch-related SVCAD resulting in syncope due to posterior left ventricular branch block. We present the case of a 59-year-old male patient who presented with syncope secondary to posterior ventricular branch block, a presentation less commonly reported in the literature. 2. Case Presentation A 59-year-old male with a known case of hypertension presented to the Emergency Department following an episode of syncope. He fell to the ground due to an episode of blackout for 5 minutes and loss of consciousness. One day back he had an episode of drowsiness, uneasiness, and diaphoresis. There was no history of chest pain. He had surgery for varicose veins 4 months before. He had a family history of Ischemic heart disease and Hypertension. He was on medications Rosuvastatin 10mg and (Amlodipine + Valsartan) 5/160mg. He had no history of addiction. On admission, his BP was 92/52 mmHg, pulse 59 beats/min, respiratory rate 16 breaths/min, and afebrile. Examination of the central nervous system, cardiovascular and respiratory system were normal. Hemoglobin (13.5 g/dL; normal: 12–15.6 g/dL) as well as coagulation factors showed no abnormality. Further laboratory results, including lipids and electrolytes were also within the normal range. His Troponin I was 1.62 ng/ml. The initial electrocardiogram (ECG) obtained in the emergency department demonstrated a normal sinus rhythm (Fig. 1 ). The echocardiogram findings indicate an ejection fraction of 55%, within the normal range, indicating normal systolic function. There were trace amounts of mitral regurgitation (MR), aortic regurgitation (AR), and tricuspid regurgitation (TR), all of which are considered minimal. Pulmonary arterial systolic pressure measures at 15mmHg, which falls within the normal range (> 25mmHg at rest and > 30mmHg during exercise). Additionally, Grade I left ventricular diastolic dysfunction (LVDD) is observed, along with an elevated E/E ratio of 12, indicating impaired left ventricular relaxation and elevated filling pressures. He was managed on Intravenous Enoxaparin Sodium 60mg bid, oral Acetylsalicylic acid 75mg OD, oral rosuvastatin 20mg Hs, oral betahistine dihydrochloride 60mg OD and oral clopidogrel bisulphate 75mg OD. His Troponin I was repeated which was 2.81 ng/ml. Physical examination was again normal. The subsequent electrocardiogram (ECG) obtained revealed Atrioventricular (AV) Dissociation (Fig. 2 ). He was managed with Intravenous furosemide 40mg stat. His Left Heart Catheterization showed, mild stenosis of the Left main coronary artery, 20% stenosis of the Left anterior descending coronary artery was noted. There was early bifurcating 100% thrombus of Posterior Left Ventricular branch at the Right coronary artery (Fig. 4 ) and Left Circumflex Coronary artery shows 70% obstruction at its distal end. The Patient went into a Complete Heart Block. He maintained all the vital signs and became asymptomatic. Initially, percutaneous coronary intervention (PCI) was performed targeting the left circumflex artery, followed by Plain Old Balloon Angioplasty (POBA) (Fig. 5) to the posterior left ventricular branch. Subsequently, a temporary pacemaker was applied through the right femoral approach. He was maintained on Intravenous fluid 50cc every hour for 12 hours. Intravenous fluids and K-lyco were stopped after 12 hours. Serum Potassium was 3.7mmol/l (normal range = 3.5-5.0 mmol/l). And the patient was maintained on Dual Antiplatelet Therapy and enoxaparin sodium. Post Percutaneous coronary Intervention Electrocardiogram showed a paced rhythm (Fig. 3 ). He was managed with the replacement of serum potassium and oral Atorvastatin 20mg Hs. Dual Antiplatelet Therapy and enoxaparin sodium were maintained. His BP was 119/65 mmHg, pulse 68 beats/min. His 24-hour ambulatory ECG was normal. The patient was planned to mobilize out of bed. On review of 8 days after Percutaneous coronary Intervention and temporary pacemaker placement, Patient remained well and asymptomatic with no episodes of syncope and normal Holter monitoring. He was maintained on clopidogrel bisulphate, Anticoagulants acetylsalicylic acid and Statins. 3. Discussion Syncope, characterized by self-limited transient loss of consciousness, remains a diagnostic challenge due to its diverse causes, ranging from benign to life-threatening conditions [ 4 ]. While cardiac causes are prominent among the differential diagnoses, syncope attributed to isolated posterior left ventricular branch block is exceptionally rare, with limited reported cases in the literature. The posterior left ventricular (PLV) artery, also known as the posterolateral branch supplies blood to the lower part of the heart. This branch is a terminal branch of the coronary artery system. It typically emerges from the right coronary artery and flows into the right circulation, usually as a terminal branch alongside the posterior descending artery. However, it also rarely originates from the left anterior descending artery and less commonly from the circumflex artery[ 5 ]. Diagnosis of syncope requires a comprehensive evaluation, including a detailed clinical history, physical examination, and diagnostic testing [ 6 ]. An electrocardiogram (ECG) is an essential tool for determining the cause of cardiac syncope. In our case, the initial ECG showed normal sinus rhythm, highlighting the importance of a high index of suspicion for subtle abnormalities. Further echocardiography and left heart catheterization confirmed a block of the posterior left ventricular branch block, an uncommon finding in people with syncope. Detailed information about the heart's structure and function is obtained through echocardiography [ 7 ], while left heart catheterization confirms the presence of coronary artery lesions and posterior left ventricular branch block [ 8 ]. A multidisciplinary approach is necessary to manage syncope caused by the left posterior ventricular branch block, that emphasizes underlying the cardiac pathology and preventing its recurrence. Revascularization techniques, including Percutaneous Coronary Intervention(PCI) or Coronary Artery Bypass Grafting (CABG), may be employed to relieve myocardial ischemia and restore perfusion within the affected myocardium[ 9 ]. PCI, targeting the left circumflex artery and subsequent POBA over the obstructed posterior left ventricular branch were successful in expediting our intervention to restore coronary perfusion and reducing myocardial ischemia. Also, temporary pacing restored complete heart block and stabilized hemodynamic functioning. 4. Conclusion This case report elaborates syncope being a rare and uncommon clinical presentation of posterior ventricular branch block. This report emphasizes upon the awareness of this very unusual presentation, being a challenge for cardiologists to diagnose and manage .This case emphasizes the need for complete and thorough evaluation of patients presenting with syncope, especially when initial investigations do not reveal common causes. By utilizing percutaneous coronary intervention and temporary pacing, this patient was successfully treated which highlights the significance of acknowledging these uncommon causes of cardiac syncope in our efforts to treat them effectively. This study highlights the importance of thorough monitoring and precise diagnosis and need for further research and discussion in similar situations. Further studies and case reports will be necessary to better understand the clinical features and management of PLV-related syncope. Declarations Funding : Not Applicable Ethical Approval: Not Applicable Conflicts of interest/Competing interests: Not applicable Consent to participate: consent was obtained from the patient to participate in this report. Written Consent for publication: Informed consent was obtained from the patient for the publication of this report and any accompanying images. Availability of data and material: Not applicable Code availability: Not applicable Authors' contributions: A.W.A: Wrote the main manuscript text. Substantial contributions to the conception or design of the work. Drafting the work or revising it critically for important intellectual content. I.S: Drafting the work or revising it critically for important intellectual content. Final approval of the version to be published. A.A: Drafting the work or revising it critically for important intellectual content. Final approval of the version to be published. A.Q: Prepared figures 1-5. A.P.A: Prepared figures 1-5. All authors reviewed the manuscript. References Chen, L. Y., Shen, W. K., Mahoney, D. W., Jacobsen, S. J., & Rodeheffer, R. J. (2006). Prevalence of syncope in a population aged more than 45 years. The American journal of medicine, 119(12), 1088.e1–1088.e10887.https://doi.org/10.1016/j.amjmed.2006.01.029 Brignole, M., Moya, A., de Lange, F. J., Deharo, J. C., Elliott, P. M., Fanciulli, A., Fedorowski, A., Furlan, R., Kenny, R. A., Martín, A., Probst, V., Reed, M. J., Rice, C. P., Sutton, R., Ungar, A., van Dijk, J. G., & ESC Scientific Document Group (2018). 2018 ESC Guidelines for the diagnosis and management of syncope. European heart journal, 39(21), 1883–1948. https://doi.org/10.1093/eurheartj/ehy037 ORFORD, J. L., & Berger, P. B. (2016). Single-Vessel Disease: Medical and Revascularization Options. Retrieved from https://thoracickey.com/single-vessel-disease-medical-and-revascularization-options/ Puppala, V. K., Dickinson, O., & Benditt, D. G. (2014). Syncope: classification and risk stratification. Journal of cardiology, 63(3), 171–177. https://doi.org/10.1016/j.jjcc.2013.03.019 Weerakkody Y, Feger J, Hacking C, et al. Posterior left ventricular artery. Reference article, Radiopaedia.org (Accessed on 28 Apr 2024) https://radiopaedia.org/articles/58074 Brignole, M., Moya, A., de Lange, F. J., Deharo, J. C., Elliott, P. M., Fanciulli, A., Fedorowski, A., Furlan, R., Kenny, R. A., Martín, A., Probst, V., Reed, M. J., Rice, C. P., Sutton, R., Ungar, A., van Dijk, J. G., & ESC Scientific Document Group (2018). 2018 ESC Guidelines for the diagnosis and management of syncope. European heart journal, 39(21), 1883–1948. https://doi.org/10.1093/eurheartj/ehy037 Omerovic, S., & Jain, A. (2023). Echocardiogram. In StatPearls. StatPearls Publishing.( https://pubmed.ncbi.nlm.nih.gov/32644366/) Ahmed I, Hajouli S. Left Heart Cardiac Catheterization. [Updated 2023 Jul 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK564323/ Amsterdam, E. A., Wenger, N. K., Brindis, R. G., Casey, D. E., Jr, Ganiats, T. G., Holmes, D. R., Jr, Jaffe, A. S., Jneid, H., Kelly, R. F., Kontos, M. C., Levine, G. N., Liebson, P. R., Mukherjee, D., Peterson, E. D., Sabatine, M. S., Smalling, R. W., Zieman, S. J., ACC/AHA Task Force Members, & Society for Cardiovascular Angiography and Interventions and the Society of Thoracic Surgeons (2014). 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation, 130(25), 2354–2394. https://doi.org/10.1161/CIR.0000000000000133 Additional Declarations No competing interests reported. Supplementary Files CAREchecklistEnglish2013.docx Cite Share Download PDF Status: Posted Version 1 posted 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6589779","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":467156484,"identity":"8ffae0f2-caac-4805-9864-be0c977b279b","order_by":0,"name":"Ammara Waheed 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18:23:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6589779/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6589779/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":84215903,"identity":"718ca387-db1a-4f59-a590-421b316da44a","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":563843,"visible":true,"origin":"","legend":"\u003cp\u003eThis initial electrocardiogram (ECG) obtained in the emergency department demonstrated a normal sinus rhythm.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/45931990de560bb2c5e33da2.png"},{"id":84215911,"identity":"41d5f370-1670-4bbb-9afe-13f2cec49810","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":442593,"visible":true,"origin":"","legend":"\u003cp\u003eThe subsequent electrocardiogram (ECG) obtained revealed Atrioventricular (AV) Dissociation.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/895481120a687a48a3948cc0.png"},{"id":84215906,"identity":"5284b7d8-f46a-4e2d-88f4-c5c79c5b0c17","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":567755,"visible":true,"origin":"","legend":"\u003cp\u003ePost Percutaneous Coronary Intervention ECG showed paced rhythm.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/31c2795725a844b8f50fe4e2.png"},{"id":84215904,"identity":"c9b92cf4-dce5-40a6-bdb0-506487056a76","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":423959,"visible":true,"origin":"","legend":"\u003cp\u003eEarly bifurcating 100% thrombus of Posterior left Ventricular branch at RCA.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/c9bd9da8072d4ff44ce9a31c.png"},{"id":84215902,"identity":"ef09c588-a1bf-4f85-9e6c-1c29a7cb2f3c","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":337008,"visible":true,"origin":"","legend":"\u003cp\u003eThe PLV branch of the RCA was wired, followed by thrombus aspiration using a Thrombuster device. Subsequently, the lesion was balloon dilated with a 1.5 × 12 mm balloon.\"\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/6496c2698334bf5b8a8b1655.png"},{"id":84617374,"identity":"24ed69d3-7130-4d8b-99b7-456b416bd8ae","added_by":"auto","created_at":"2025-06-14 20:01:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2863790,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/5d4e26fe-d9b1-4c5a-bbe7-849492a10f44.pdf"},{"id":84215905,"identity":"22a46b01-516a-4f2e-95e9-f7d460152f65","added_by":"auto","created_at":"2025-06-09 10:39:19","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":94290,"visible":true,"origin":"","legend":"","description":"","filename":"CAREchecklistEnglish2013.docx","url":"https://assets-eu.researchsquare.com/files/rs-6589779/v1/3e990ddd10ed18a06e8df91c.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eCase Report: A Rare Presentation of Posterior Left Ventricular Branch Block Associated With Syncope\u003c/p\u003e","fulltext":[{"header":"1. Background","content":"\u003cp\u003eSyncope is a clinical problem with a prevalence of 19% in the general population[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Despite advancements in recent years, the reason for 10% of cases remains unknown[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Although cardiac reasons continue to be a major factor, the very uncommon correlation between posterior left ventricular branch block and syncope is worth mentioning. Single-vessel coronary artery disease is defined as stenosis of at least 70% or more of one major coronary artery, i.e the Left Circumflex or Right coronary artery, Left Anterior Descending or any of their respective branch i.e Obtuse, Posterior left ventricular artery, Posterior Descending Artery or Diagonal artery[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] is acknowledged for its broad spectrum of clinical manifestations. However, there is few data linking it to syncope, particularly regarding the involvement of the posterior left ventricular branch. Awareness of this unusual presentation allows the recording of rare clinical situations and helps cardiologists improve diagnostic methods that may encounter similar cases in their general clinical practice. Here we describe the management of a patient with the distal circumflex branch-related SVCAD resulting in syncope due to posterior left ventricular branch block. We present the case of a 59-year-old male patient who presented with syncope secondary to posterior ventricular branch block, a presentation less commonly reported in the literature.\u003c/p\u003e"},{"header":"2. Case Presentation","content":"\u003cp\u003eA 59-year-old male with a known case of hypertension presented to the Emergency Department following an episode of syncope. He fell to the ground due to an episode of blackout for 5 minutes and loss of consciousness. One day back he had an episode of drowsiness, uneasiness, and diaphoresis. There was no history of chest pain. He had surgery for varicose veins 4 months before. He had a family history of Ischemic heart disease and Hypertension. He was on medications Rosuvastatin 10mg and (Amlodipine\u0026thinsp;+\u0026thinsp;Valsartan) 5/160mg. He had no history of addiction.\u003c/p\u003e\n\u003cp\u003eOn admission, his BP was 92/52 mmHg, pulse 59 beats/min, respiratory rate 16 breaths/min, and afebrile. Examination of the central nervous system, cardiovascular and respiratory system were normal.\u003c/p\u003e\n\u003cp\u003eHemoglobin (13.5 g/dL; normal: 12\u0026ndash;15.6 g/dL) as well as coagulation factors showed no abnormality. Further laboratory results, including lipids and electrolytes were also within the normal range. His Troponin I was 1.62 ng/ml. The initial electrocardiogram (ECG) obtained in the emergency department demonstrated a normal sinus rhythm (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). The echocardiogram findings indicate an ejection fraction of 55%, within the normal range, indicating normal systolic function. There were trace amounts of mitral regurgitation (MR), aortic regurgitation (AR), and tricuspid regurgitation (TR), all of which are considered minimal.\u003c/p\u003e\n\u003cp\u003ePulmonary arterial systolic pressure measures at 15mmHg, which falls within the normal range (\u0026gt;\u0026thinsp;25mmHg at rest and \u0026gt;\u0026thinsp;30mmHg during exercise). Additionally, Grade I left ventricular diastolic dysfunction (LVDD) is observed, along with an elevated E/E ratio of 12, indicating impaired left ventricular relaxation and elevated filling pressures. He was managed on Intravenous Enoxaparin Sodium 60mg bid, oral Acetylsalicylic acid 75mg OD, oral rosuvastatin 20mg Hs, oral betahistine dihydrochloride 60mg OD and oral clopidogrel bisulphate 75mg OD. His Troponin I was repeated which was 2.81 ng/ml. Physical examination was again normal. The subsequent electrocardiogram (ECG) obtained revealed Atrioventricular (AV) Dissociation (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). He was managed with Intravenous furosemide 40mg stat. His Left Heart Catheterization showed, mild stenosis of the Left main coronary artery, 20% stenosis of the Left anterior descending coronary artery was noted. There was early bifurcating 100% thrombus of Posterior Left Ventricular branch at the Right coronary artery (Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e) and Left Circumflex Coronary artery shows 70% obstruction at its distal end. The Patient went into a Complete Heart Block. He maintained all the vital signs and became asymptomatic. Initially, percutaneous coronary intervention (PCI) was performed targeting the left circumflex artery, followed by Plain Old Balloon Angioplasty (POBA) (Fig. 5) to the posterior left ventricular branch. Subsequently, a temporary pacemaker was applied through the right femoral approach. He was maintained on Intravenous fluid 50cc every hour for 12 hours. Intravenous fluids and K-lyco were stopped after 12 hours. Serum Potassium was 3.7mmol/l (normal range\u0026thinsp;=\u0026thinsp;3.5-5.0 mmol/l). And the patient was maintained on Dual Antiplatelet Therapy and enoxaparin sodium. Post Percutaneous coronary Intervention Electrocardiogram showed a paced rhythm (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). He was managed with the replacement of serum potassium and oral Atorvastatin 20mg Hs. Dual Antiplatelet Therapy and enoxaparin sodium were maintained. His BP was 119/65 mmHg, pulse 68 beats/min. His 24-hour ambulatory ECG was normal. The patient was planned to mobilize out of bed. On review of 8 days after Percutaneous coronary Intervention and temporary pacemaker placement, Patient remained well and asymptomatic with no episodes of syncope and normal Holter monitoring. He was maintained on clopidogrel bisulphate, Anticoagulants acetylsalicylic acid and Statins.\u003c/p\u003e"},{"header":"3. Discussion","content":"\u003cp\u003eSyncope, characterized by self-limited transient loss of consciousness, remains a diagnostic challenge due to its diverse causes, ranging from benign to life-threatening conditions [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. While cardiac causes are prominent among the differential diagnoses, syncope attributed to isolated posterior left ventricular branch block is exceptionally rare, with limited reported cases in the literature.\u003c/p\u003e \u003cp\u003eThe posterior left ventricular (PLV) artery, also known as the posterolateral branch supplies blood to the lower part of the heart. This branch is a terminal branch of the coronary artery system.\u003c/p\u003e \u003cp\u003eIt typically emerges from the right coronary artery and flows into the right circulation, usually as a terminal branch alongside the posterior descending artery. However, it also rarely originates from the left anterior descending artery and less commonly from the circumflex artery[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDiagnosis of syncope requires a comprehensive evaluation, including a detailed clinical history, physical examination, and diagnostic testing [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAn electrocardiogram (ECG) is an essential tool for determining the cause of cardiac syncope. In our case, the initial ECG showed normal sinus rhythm, highlighting the importance of a high index of suspicion for subtle abnormalities.\u003c/p\u003e \u003cp\u003eFurther echocardiography and left heart catheterization confirmed a block of the posterior left ventricular branch block, an uncommon finding in people with syncope.\u003c/p\u003e \u003cp\u003eDetailed information about the heart's structure and function is obtained through echocardiography [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], while left heart catheterization confirms the presence of coronary artery lesions and posterior left ventricular branch block [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. A multidisciplinary approach is necessary to manage syncope caused by the left posterior ventricular branch block, that emphasizes underlying the cardiac pathology and preventing its recurrence. Revascularization techniques, including Percutaneous Coronary Intervention(PCI) or Coronary Artery Bypass Grafting (CABG), may be employed to relieve myocardial ischemia and restore perfusion within the affected myocardium[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. PCI, targeting the left circumflex artery and subsequent POBA over the obstructed posterior left ventricular branch were successful in expediting our intervention to restore coronary perfusion and reducing myocardial ischemia. Also, temporary pacing restored complete heart block and stabilized hemodynamic functioning.\u003c/p\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThis case report elaborates syncope being a rare and uncommon clinical presentation of posterior ventricular branch block. This report emphasizes upon the awareness of this very unusual presentation, being a challenge for cardiologists to diagnose and manage .This case emphasizes the need for complete and thorough evaluation of patients presenting with syncope, especially when initial investigations do not reveal common causes. By utilizing percutaneous coronary intervention and temporary pacing, this patient was successfully treated which highlights the significance of acknowledging these uncommon causes of cardiac syncope in our efforts to treat them effectively. This study highlights the importance of thorough monitoring and precise diagnosis and need for further research and discussion in similar situations. Further studies and case reports will be necessary to better understand the clinical features and management of PLV-related syncope.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding :\u0026nbsp;\u003c/strong\u003eNot Applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval:\u003c/strong\u003e Not Applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest/Competing interests:\u003c/strong\u003e Not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate:\u003c/strong\u003e consent was obtained from the patient to participate in this report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWritten Consent for publication:\u003c/strong\u003e Informed consent was obtained from the patient for the publication of this report and any accompanying images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material:\u003c/strong\u003e Not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCode availability:\u003c/strong\u003e Not applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA.W.A: Wrote the main manuscript text. Substantial contributions to the conception or design of the work. Drafting the work or revising it critically for important intellectual content.\u003c/p\u003e\n\u003cp\u003eI.S: Drafting the work or revising it critically for important intellectual content. \u0026nbsp; Final approval of the version to be published.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA.A: Drafting the work or revising it critically for important intellectual content. Final approval of the version to be published.\u003c/p\u003e\n\u003cp\u003eA.Q: Prepared figures 1-5. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA.P.A: Prepared figures 1-5.\u003c/p\u003e\n\u003cp\u003eAll authors reviewed the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eChen, L. Y., Shen, W. K., Mahoney, D. W., Jacobsen, S. J., \u0026amp; Rodeheffer, R. J. (2006). Prevalence of syncope in a population aged more than 45 years. The American journal of medicine, 119(12), 1088.e1\u0026ndash;1088.e10887.https://doi.org/10.1016/j.amjmed.2006.01.029 \u003c/li\u003e\n\u003cli\u003eBrignole, M., Moya, A., de Lange, F. J., Deharo, J. C., Elliott, P. M., Fanciulli, A., Fedorowski, A., Furlan, R., Kenny, R. A., Mart\u0026iacute;n, A., Probst, V., Reed, M. J., Rice, C. P., Sutton, R., Ungar, A., van Dijk, J. G., \u0026amp; ESC Scientific Document Group (2018). 2018 ESC Guidelines for the diagnosis and management of syncope. European heart journal, 39(21), 1883\u0026ndash;1948. https://doi.org/10.1093/eurheartj/ehy037\u003c/li\u003e\n\u003cli\u003eORFORD, J. L., \u0026amp; Berger, P. B. (2016). Single-Vessel Disease: Medical and Revascularization Options. Retrieved from https://thoracickey.com/single-vessel-disease-medical-and-revascularization-options/\u003c/li\u003e\n\u003cli\u003ePuppala, V. K., Dickinson, O., \u0026amp; Benditt, D. G. (2014). Syncope: classification and risk stratification. Journal of cardiology, 63(3), 171\u0026ndash;177. https://doi.org/10.1016/j.jjcc.2013.03.019\u003c/li\u003e\n\u003cli\u003eWeerakkody Y, Feger J, Hacking C, et al. Posterior left ventricular artery. Reference article, Radiopaedia.org (Accessed on 28 Apr 2024) https://radiopaedia.org/articles/58074\u003c/li\u003e\n\u003cli\u003eBrignole, M., Moya, A., de Lange, F. J., Deharo, J. C., Elliott, P. M., Fanciulli, A., Fedorowski, A., Furlan, R., Kenny, R. A., Mart\u0026iacute;n, A., Probst, V., Reed, M. J., Rice, C. P., Sutton, R., Ungar, A., van Dijk, J. G., \u0026amp; ESC Scientific Document Group (2018). 2018 ESC Guidelines for the diagnosis and management of syncope. European heart journal, 39(21), 1883\u0026ndash;1948. https://doi.org/10.1093/eurheartj/ehy037 \u003c/li\u003e\n\u003cli\u003eOmerovic, S., \u0026amp; Jain, A. (2023). Echocardiogram. In StatPearls. StatPearls Publishing.( https://pubmed.ncbi.nlm.nih.gov/32644366/) \u003c/li\u003e\n\u003cli\u003eAhmed I, Hajouli S. Left Heart Cardiac Catheterization. [Updated 2023 Jul 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK564323/\u003c/li\u003e\n\u003cli\u003eAmsterdam, E. A., Wenger, N. K., Brindis, R. G., Casey, D. E., Jr, Ganiats, T. G., Holmes, D. R., Jr, Jaffe, A. S., Jneid, H., Kelly, R. F., Kontos, M. C., Levine, G. N., Liebson, P. R., Mukherjee, D., Peterson, E. D., Sabatine, M. S., Smalling, R. W., Zieman, S. J., ACC/AHA Task Force Members, \u0026amp; Society for Cardiovascular Angiography and Interventions and the Society of Thoracic Surgeons (2014). 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation, 130(25), 2354\u0026ndash;2394. https://doi.org/10.1161/CIR.0000000000000133\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Posterior left ventricular branch block, Syncope, PCI, POBA, Temporary pacemaker","lastPublishedDoi":"10.21203/rs.3.rs-6589779/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6589779/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSyncope characterized by self-limited transient loss of consciousness , affecting 19% of population remains diagnostically challenging with 10% cases unexplained.\u003c/p\u003e\n\u003cp\u003eRarely syncope links to posterior left ventricular branch block, a less reported phenomenon, highlighting need for improved diagnostic approaches.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA 59 year old hypertensive male, presented with syncope with initial normal examinations. Elevated Troponin I levels and subsequent tests revealed AV dissociation and significant coronary artery stenosis, notably in left circumflex and posterior left ventricular branches.\u003c/p\u003e\n\u003cp\u003eThis led to a complete PCI targeting the left circumflex artery and plain old balloon angioplasty (POBA) to posterior left ventricular branch followed by temporary pacemaker placement. Post intervention, the patient remained stable with no occurence of syncope and normal 24 hour ambulatory ECG monitoring.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiscussion\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIsolated posterior left ventricular (PLV) branch block is a rarely- discussed topic in medical literature. This article primarily aims to review existing studies and present a detailed case study, shedding light on this rare phenomenon.\u003c/p\u003e","manuscriptTitle":"Case Report: A Rare Presentation of Posterior Left Ventricular Branch Block Associated With Syncope","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-09 10:38:45","doi":"10.21203/rs.3.rs-6589779/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"73038c20-2c20-4dab-a8dd-43ff42dbf987","owner":[],"postedDate":"June 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-14T19:53:16+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-09 10:38:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6589779","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6589779","identity":"rs-6589779","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}