Imaging techniques for diagnosing a giant coronary artery fistula

Abstract

A 72-year-old man presented with new onset heart failure. Chest radiography showed marked cardiomegaly and a dense structure contiguous with the left heart border (Fig. 1). Transthoracic echocardiography was unremarkable because of poor echogenicity. Transesophageal echocardiography (TEE) revealed a giant aneurysm located at the posterior side of the left ventricle, near the mitral annulus (Fig. 2). The enlarged circumflex artery flowed towards the left atrial appendage and fed the giant aneurysm. A provisional diagnosis of coronary fistula was made. Coronary angiography (Fig. 3) unequivocally established the diagnosis of a left coronary fistula. However, TEE and coronary angiography failed to determine the drainage site for the fistula. To trace the drainage accurately, computed tomography (CT) angiography was performed, and showed a partially thrombosed giant aneurysm (14 x 9 cm in diameter), fed by the circumflex coronary artery. The site of drainage appeared to be the main coronary vein (Figs. 4 et 5). Taking into consideration the size of the aneurysm and the heart failure, the patient was referred for surgery. The aneurysm was resected and the circumflex artery ligated, without coronary bypass because of the small size of the vessel bed (Figs. 6 et 7). The patient's postoperative course was unremarkable.