This article reports the clinical and angiographic aspects of three patients with congenital coronary arteriovenous fistula to the main pulmonary artery, which manifested as dyspnea crisis and angina. This three cases were found in the course of 4,400 consecutive cardiac catheterization procedures to study coronary artery disease. The interest of the cases reported is based on the peculiar anatomy of the fistula. Prompt diagnosis is relevant for better prognosis and treatment.