Coronary dissection and myocardial infarction following blunt chest trauma.

Myocardial infarction (MI) following blunt chest trauma is rarely diagnosed because the ensuing cardiac pain is commonly attributed to contused myocardium or the traumatic injuries in the local chest wall. There are only scattered reports on the coronary pathology associated with MI secondary to blunt chest trauma. Because differentiation of the pathology is difficult but important, we report here three cases of acute anterior MI secondary to coronary dissection following blunt chest trauma. Coronary dissection was demonstrated by coronary angiography. Two of the patients had intimal tears at the proximal left anterior descending artery (LAD) with normal flow, and the other patient had nearly total occlusion of the LAD associated with filling defects probably caused by an intracoronary thrombus. All three patients received conservative treatment without major complications and remained free from angina or heart failure throughout a 5-year follow-up period. In order to exclude associated MI in cases of blunt chest trauma, electrocardiography is necessary, and coronary angiography may be indicated to demonstrate coronary arterial pathology. Dissection of the coronary artery with subsequent thrombus formation is one of the possible pathophysiologic mechanisms of MI following blunt chest trauma.