Coexistence of Myocardial Infarction with Normal Coronary Arteries and a Left Circumflex Artery Anomaly Originating from the Right Coronary Artery with a Bridge in the Left Anterior Descending Artery

Congenital anomalies in the origin, course or distribution of the epicardial coronary arteries are found in 1 to 2 percent of the population. Asymptomatic coronary artery anomalies are generally diagnosed incidentally by routine coronary angiography or during autopsy. Approximately 80% of congenital anomalies of the coronary arteries are benign, while 20% of coronary artery anomalies produce life threatening symptoms, including arrhythmias, syncope, myocardial infarction or sudden death. These anomalies are especially dangerous when they courses between the aorta and the main pulmonary artery. It is not yet possible to determine the causes of a particular patient’s infarction. The valvular mechanism has been suggested to result from angulations at the arterial origin or from the compression of the artery between the aorta and the pulmonary artery during exercise. In some cases, spasms of the abnormal coronary artery (possibly due to endothelial damage) or arteriosclerosis have been considered to be the reasons for coronary arterial occlusion. We report a patient with two coronary anomalies, a left circumflex coronary artery (LCX) originating from the proximal right coronary artery (RCA) and a muscular bridge in the left anterior descending (LAD) midportion, who underwent successful fibrinolytic therapy for an inferolateral myocardial infarction.