Congenital circumflex coronary artery fistulae; presentation and diagnosis.

Small fistulae between coronary arteries and the pulmonary artery are common, but abnormal vascular communications between the coronary arteries and other cardiac structures are rare. They were first described by Krause in 1865. We report two cases of fistulous connexions between the circumflex coronary artery and the coronary sinus.