Incidental left anterior descending coronary artery-pulmonary artery fistula with a fistulous aneurysm: CT angiography characterization and management

Coronary artery fistulas (CAFs) are rare vascular anomalies characterized by an abnormal connection between a coronary artery and a cardiac chamber or the great vessels. The coronary-pulmonary artery fistula (CPAF) is the most common subtype, often detected incidentally on cardiac imaging but occasionally leading to significant clinical consequences. CPAFs are most often congenital but can also be acquired due to trauma or iatrogenic causes. Diagnosis relies on imaging, including CT angiography (CTA) for detailed anatomical assessment. Management decisions depend on symptoms and risk of complications. We present a 73-year-old woman with a history of hypertension, hyperlipidemia, and prior tobacco use, referred for evaluation of a CPAF arising from the left anterior descending (LAD) artery with a saccular aneurysm in the course of the fistula. From the cardiovascular standpoint, the patient was asymptomatic. Given the asymptomatic condition and absence of hemodynamic disturbance, conservative management with annual imaging follow-up was recommended. This case highlights the importance of correlating imaging findings with clinical context through multimodal evaluation and personalized management in patients with incidentally discovered CPAFs, particularly when aneurysmal change is present. Careful longitudinal follow-up is essential to monitor interval growth and assess hemodynamic stability, which dictate the appropriate course of management.