A Rare Case of Isolated Single Coronary Artery, Lipton's Type R-IIB in an Elderly Woman With Recurrent Chest Pain and Left Bundle Branch Block: A Case Report.

Single coronary artery (SCA) is a rare congenital coronary anomaly arising from a solitary ostium, supplying the entire myocardium. Often asymptomatic and incidental, those with inter-arterial courses carry an increased risk of arrhythmia or sudden cardiac death (SCD). We report a case of SCA in an elderly woman with recurrent chest pain and left bundle branch block (LBBB). Angiogram revealed an anomalous Lipton type R-IIb SCA arising from the right coronary sinus with a malignant inter-arterial course confirmed by coronary CTA. She was referred for surgery due to the risk of SCD and malignant arrhythmia. SCA represents a rare but clinically significant coronary anomaly, particularly those with a malignant course. Early recognition and detailed anatomical characterization using noninvasive and invasive imaging techniques are crucial for accurate diagnosis and risk assessment.