Anomalous Left Coronary Artery Originating From the Right Coronary Sinus With a Septal Curse in a Patient With Myocardial Infarction Due to Right Coronary Lesion: Innocent Until Proven Otherwise

Coronary artery anomalies (CAAs) are rare and challenging, with increased diagnoses due to advanced cardiovascular imaging, even in low-income countries where diagnostic and therapeutic approaches can be difficult. This case report details a 65-year-old Black male patient with a history of hypertension and smoking who presented with a myocardial infarction. Despite no significant abnormalities apart from the infarction, invasive coronary angiography revealed a dominant right coronary artery (RCA) and an anomalous left main coronary artery (LMCA) originating from the right coronary sinus, bifurcating into the left anterior descending artery and circumflex artery. An 80% stenotic lesion in the distal RCA was treated with percutaneous transluminal coronary angioplasty (PTCA) and drug-eluting stent implantation. Coronary computed tomography angiography (CCTA) confirmed the findings, detailing the anomalous LMCA's course. This case underscores the rarity and clinical significance of CAAs, particularly an anomalous LMCA with a septal course, as a diagnostic challenge and the impact of course study on therapeutic decision-making. While conservative treatment is generally recommended, surgical intervention may be necessary for high-risk cases. For this patient, the current myocardial infarction was due to atherosclerotic disease in the RCA, effectively treated with PTCA and stent placement. The percutaneous treatment of RCA stenosis, despite the anomalous LMCA without significant atherosclerosis, appears to be effective and safe.