Anomalous Great Cardiac Vein Mistaken for Left Main Coronary Artery Aneurysm in a Case of Anomalous Left Coronary Artery Arising from the Main Pulmonary Artery

Anomalous coronary venous drainage is rare and likely to be under-reported, with many cases found incidentally in cardiac imaging and autopsy studies. It may also occasionally have an important clinical implication. We report a rare case of anomalous great cardiac vein bypassing the coronary sinus to drain directly into the left brachiocephalic vein in a patient with anomalous left coronary artery arising from the main pulmonary artery. This anomalous course resulted in a misdiagnosis of coronary aneurysm on echocardiography.