A patient with pulmonary atresia and intact ventricular septum was found to have a right ventricular-dependent coronary circulation. In this infant both coronary arteries lacked their normal proximal connection with the aorta, perhaps the most egregious form of this prejudicial coronary circulation. Even more interesting was a direct collateral vessel originating from the descending thoracic aorta and connecting with the coronary circulation. This patient has undergone bilateral modified Blalock-Taussig shunts, and left ventricular function seems preserved.
