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

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.