Three patients aged 52, 22 and 29 years, without known previous heart disease, sustained acute myocardial infarction due to blunt chest trauma. A 52-year-old man without a history of heart disease sustained an acute non-transmural lateral myocardial infarction following blunt chest trauma during a sledging party. No coronary arteriography was performed. The clinical course during follow-up of 3 1/2 years was uncomplicated. A 22-year-old, previously asymptomatic man developed acute transmural anteroseptal infarction after a motor-cycle accident. Seven days later he died suddenly after an uncomplicated initial course. The autopsy demonstrated a complete rupture of the proximal left anterior descending artery with periarterial hemorrhage, compression of this artery by the hemorrhage and luminal thrombosis distal to the rupture. No sign of preexisting atherosclerotic coronary disease was found. A 29-year-old man admitted to the hospital after blunt chest trauma during a football game developed an acute transmural inferior infarction with an uncomplicated clinical course. Seven months later coronary arteriography demonstrated a 40% obstructive lesion of the right coronary artery, compatible with thrombosis and subsequent recanalization.