[Simultaneous thrombosis of the left anterior interventricular and right coronary arteries in a 27 year-old patient with protein S deficiency].

The authors report a case of myocardial infarction in a 27 year old patient by simultaneous thrombosis of the left anterior descending and right coronary arteries in an angiographically normal coronary circulation. The young age of the patient, the absence of the usual risk factors and a normal angiographic network after arterial recanalisation by angioplasty led to the search for a risk factor of thrombosis. This showed a qualitative deficiency of protein S and the absence of any other abnormality of coagulation or fibrinolysis. This case raises the question of a causal relationship between a hereditary protein S deficiency and thrombotic arterial occlusion.