Imaging-Based Diagnosis of a Right Coronary Artery-to-Left Anterior Descending Artery Fistula Associated With a Double Right Coronary Artery Presenting With Angina.

Coronary artery fistulas (CAFs) are uncommon coronary anomalies that are often asymptomatic but may present later in life due to the coronary steal phenomenon, leading to myocardial ischemia and related complications. We report the case of a 76-year-old male presenting with anginal chest pain. Coronary computed tomography angiography performed after inconclusive prior cardiac testing revealed a direct fistulous communication between the right coronary artery (RCA) and the left anterior descending artery (LAD), an exceptionally rare configuration. Imaging also demonstrated a double RCA, an uncommon congenital variant characterized by two parallel right coronary arteries arising from a single or separate ostia, which may coexist with other coronary anomalies and complicate interpretation. The study showed a tortuous fistulous tract with features consistent with chronic high-flow physiology and coronary steal, correlating with the patient's clinical presentation. This case highlights the importance of considering rare coronary anomalies in elderly patients with new-onset angina and underscores the value of coronary computed tomography angiography in providing detailed three-dimensional visualization of coronary anatomy, enabling definitive diagnosis and guiding clinical management in complex coronary vascular anomalies.