[Myocardial infarction caused by thrombosis of the left coronary artery in a patient with thrombocythemia].

Myocardial infarction is not exceptional in patients with essential thrombocythaemia. This infarction is often related to the formation of in situ coronary thrombosis with no associated atheromatous lesions. The authors report the case of a thrombocythaemic patient with anterior infarction due to thrombosis of the left coronary artery. The clinical course is often more severe than in nonthrombocythaemic patients. The pathophysiological mechanisms remain unclear, but appear to be related to qualitative rather than quantitative platelet abnormalities.