Acute myocardial infarction in a patient with coronary artery aneurysm

A coronary artery aneurysm (CAA) is defined as the dilatation of a coronary artery that exceeds the diameter of normal adjacent segments or the diameter of largest coronary vessel (in the case of left main coronary artery) by 1.5 times. The incidence reported varies from 1.5% to 5% among patients that underwent coronarography with male dominance. CAAs are usually multiple and atherosclerotic in origin in more than 50% of the diagnosed adult cases in the Western world. Reported complications include thrombosis and distal embolization, rupture and vasospasm. A case of a patient with myocardial infarction due to coronary artery aneurysm was reported. Case report: A 56-year-old male presented to the emergency department complained of acute chest pain accompanied by nausea, vomiting and diaphoresis lasting for one hour. The physical examination was unremarkable. A 12-lead electrocardiogram revealed a normal sinus rhythm with ST segment elevation in anterior and lateral leads I, aVL and V2-V6. Laboratory tests showed elevation of plasma total creatine phosphokinase (CPK), CPKMB and troponin I activities. Acute anterior and lateral wall myocardial infarction was diagnosed. The therapy consisted of nitroglycerin, unfractionated heparin, dual antiplatelet therapy and beta blocker, followed by thrombolytic therapy with streptokinase since there were not any catheterization labs in the region. A transthoracic echocardiogram showed a left ventricular ejection fraction of 40%. The patient remained asymptomatic and hemodynamically stable during the whole course of hospitalization and was discharged with the recommendation for the full work up in his place of residency. One month later patient underwent coronary angiography. Coronary angiography revealed a 6x6 mm aneurysm of the proximal left anterior descending coronary artery and 6x5 mm aneurysm of the left circumflex coronary artery. There was no significant coronary stenosis so aneurysms thrombosis were presumed to be the cause of infarction. The patient was referred to the cardiovascular surgeon who did not recommend any coronary intervention. The patient was advised to continue with medical therapy including oral anticoagulants, aspirin, ACE inhibitor, calcium channel blocker, beta blocker, diuretics, statin and mild sedative. During the one-year follow up examination the patient remained asymptomatic. This case report emphasizes the importance of diagnostic work up including coronary angiography in the evaluation of patients presenting with ST elevation myocardial infarction.