[Coronary arteriovenous fistula. Study of 14 cases].

Fourteen cases of coronary arteriovenous fistulae observed at the Instituto Nacional de Cardiología Ignacio Chávez were analyzed. The fistula originated from the right coronary artery in 57.1% of the cases, from the left coronary artery in 35.7% and from both coronary arteries in 7.2%. Drainage occurred into the right ventricle in 71.4% of the cases, into the right atrium in 7.2% and into the main pulmonary artery in 21.4%. The physical, roentgenological and electrocardiographic findings are undistinguishable from those usually obtained in malformations with a shunt between the aorta and the right heart or the pulmonary artery. Definite diagnosis is made at angiography. 2D and Doppler echocardiography may also be very useful. Natural history depends on the age of the patient, the size of the arteriovenous shunt, the presence of pulmonary hypertension and the development of complications. Even though malformations with small shunts may be well tolerated, serious complications are frequent and, thus, 14.3% of the patients developed infective endocarditis, 42.9% were in heart failure, 14.3% complained of angina pectoris and 54.5% had pulmonary hypertension. Mortality in this series was 28.6%. Early elective ligation seems to be the optimal treatment of coronary arteriovenous fistulae. The surgical procedure, however, is not devoid of risk. Thus, two of the three patients in this series who were operated upon after 1967 developed perioperative myocardial infarctions. Improvement in surgical technique should prevent this complication.