[Myocardial infarct in a young man with normal coronary vessels: apropos of a clinical case treated with streptokinase].

The authors report a case of a 31 year old young man who suffered acute myocardial infarction and was subjected to early treatment with streptokinase. The immediate follow-up showed a complete recanalization of the infarct-related vessel, without any identifiable obstructive lesion on coronary arteriography. Related to this angiographic finding, common in myocardial infarction in the young adult, the authors debate the implicated mechanisms, focusing essentially in the relation endothelium-platelets-vasomotricity. The issue of cigarette smoking as a risk factor and its possible pathogenic implication, even in the absence of atherosclerotic plaque, is also approached.