[Atresia of the left coronary ostium. Repair in a 2-month-old infant].

A case of atresia of the left coronary ostium revealed by neonatal heart failure is reported. The initial diagnosis was anomalous origin of the left coronary artery from the pulmonary artery. At surgery performed in this 6-week old infant the diagnosis was amended and the malformation was repaired. Soon after the operation the child rapidly developed hypertrophic "myocardiopathy" of the left ventricle. Seven and a half months later, he is asymptomatic and the echocardiographic parameters of left ventricular systolic function are gradually returning to normality. Atresia of the left coronary ostium is an exceptional anomaly which must be considered, together with the other anomalous origins of the left coronary artery, when confronted with a case of severe heart failure caused by coronary ischaemia during the first months of life. The diagnosis rests on opacification of the coronary network during cardiac catheterization. Coronary "revascularization" may be performed either by aortocoronary bypass or by anatomical repair of the malformation.