A Giant Aneurysm of Vieussens' Arterial Ring With Pulmonary Artery Fistula.

A 79-year-old woman presented with a systolic murmur and dyspnea on exertion. Transthoracic echocardiography and multidetector-row computed tomography revealed a giant aneurysm in an abnormal vessel known as Vieussens' arterial ring (VAR). A pulmonary artery VAR fistula was also observed. Cardiac catheterization revealed a high pulmonary-to-systemic flow ratio (Qp/Qs = 2.1). We ligated the VAR, resected the aneurysm, and closed the fistula using a bovine pericardial patch. The patient's postoperative clinical course was uneventful.