Abstract
BACKGROUND: Coronary artery anomalies occur in 0.03% to 0.28% of the population, with anomalous left circumflex artery from right pulmonary artery (AoLCx-RPA) a rare subset associated with increased ischemia risk and cardiac death. Early recognition and functional assessment are essential for optimal management given limited guidelines. CASE SUMMARY: We present a 43-year-old man with no significant history who developed 1-month exertional dyspnea, electrocardiographic changes, and elevated troponin concerning for non-ST-segment elevation myocardial infarction. Coronary angiography revealed nonobstructive arteries with retrograde filling via right coronary artery collaterals, suggestive of anomalous left circumflex artery. Multimodal imaging-including computed tomography angiography, cardiac magnetic resonance, and positron emission tomography-confirmed AoLCx-RPA with ischemia, prompting surgical correction. DISCUSSION: This case highlights diagnostic and treatment pathways for AoLCx-RPA, contributing to limited evidence. We discuss current guidelines, multimodal imaging's role in evaluating anatomic and functional significance, and advanced hybrid imaging's utility in management. TAKE-HOME MESSAGE: Clinical suspicion for coronary anomalies may warrant multimodal imaging and multidisciplinary approach for risk stratification and outcome optimization.