Coronary artery ectasia is defined as a > 1.5-fold dilation of the coronary artery compared to the diameter of adjacent normal segments. It must be distinguished from discrete aneurysms that appear in areas adjacent to coronary artery stenosis. It is usually considered a variant of coronary atherosclerosis. Dilated segments are thought to modify the rheology of blood, sluggish or turbulent flow predisposing to myocardial ischemia and its sequelae, including myocardial infarction and sudden death. We report the case of a 52-year-old man, light smoker, with arterial hypertension and family history of coronary artery disease, who was referred to our coronary care unit for an inferior ST-elevation acute myocardial infarction and presented with severe and diffuse vessel ectasia and right coronary thrombosis at coronary angiography.