Thrombosis of epicardial coronary veins in acute myocardial infarction.

Thrombosis of epicardial coronary veins was demonstrated in 16 of 50 cases of left ventricular acute myocardial infarction and/or recent coronary arterial thrombosis. All patients with valvular heart disease had venous thrombosis. In cases without valvular heart disease, venous thrombosis was seen in infarctions involving more than 30% of the left ventricular myocardial mass with a post-attack survival time of at least 24 hours. The veins thrombosed were in all cases those draining the infarcted myocardium. Coronary vein thrombosis seems not to be prevented by anticoagulant medication.