The authors report the case of a 45 year old woman presenting with inaugural anterior myocardial infarction due to spontaneous dissection of the left main and principal branches of the left coronary arterial system. Two attempts of thrombolysis at a one hour interval were made within 6 hours of the onset of symptoms with signs of reperfusion but the ECG and echocardiography showed anterolateral myocardial infarction. A recurrence of chest pain on the fifth day led to emergency coronary angiography. The extent and severity of the observed lesions led to emergency surgical revascularisation with no post-operative complications. Skin biopsy showed signs of dystrophy of the elastic tissues. Angiographic control ten months after surgery showed complete regression of the lesions, especially those of the left main coronary with, however, occlusion of the second segment of the left anterior descending artery and sequellae of anterior myocardial infarction. Treatment of this type of disease is difficult as the outcome is unpredictable and has to be decided case by case.