[Congenital anomalies of the coronary arteries with associated ischemic ST depression on exercise: a report of three cases].

This report presented evidence of myocardial ischemia as the etiology of angina pectoris in three patients with congenital anomalies of the coronary arteries but without arteriosclerotic disease. All of three cases showed angina pectoris and ST depressions on their exercise electrocardiogram. Case 1: This 58-year-old man developed angina pectoris at the age of 50 years. His treadmill exercise test precipitated chest pain and ST depression. His coronary arteriograms disclosed an ectopic origin of the right coronary artery just anterior to the origin of the left coronary artery in the left coronary sinus. No significant atherosclerotic stenosis was present. An apparent ischemic manifestation appeared to be caused by compression of an aberrant right coronary artery between the aorta and the right ventricular infundibulum. Case 2: A 49-year-old woman had a history of angina. Her treadmill exercise test induced chest pain and an abnormal exercise electrocardiographic finding. Her coronary arteriograms revealed a single left coronary artery. Insufficient perfusion was postulated as a cause of apparent myocardial ischemia in this case though angiographically, there was adequate perfusion. Case 3: This 31-year-old man had a six-year history of angina. His treadmill exercise electrocardiograms revealed ischemic changes accompanied by chest pain. Coronary arteriograms disclosed a coronary artery fistula. The ischemic manifestation was apparently caused by inadequate perfusion due to coronary steal. With the increasing use of coronary arteriography, unusual origins and courses of coronary arteries will be more frequently encountered. Precise knowledge of anomalies is prerequisite for evaluating variations in the location of the coronary artery ostia and their statistical probabilities.