Congenital Abnormalities of Coronary Arteries

Abstract

Congenital coronary artery anomalies are due to abnormal origin. Two types of abnormal origin are recognized: Abnormal origin from pulmonary artery instead of the aorta (ALCAPA) results in myocardial ischemia and dilated cardiomyopathy like clinical presentation in early infancy. Abnormal origin of coronary artery from wrong coronary sinus within the aortic root, particularly the left coronary artery from right coronary sinus may result in acute compromise of coronary blood perfusion associated with exercise which may present as sudden death. All infants presenting with dilated cardiomyopathy must be investigated for ALCAPA. Although echocardiography is helpful in making this diagnosis, cardiac catheterization and angiography may be needed to ensure normal origin of coronary arteries. Electrocardiography may be diagnostic in abnormal origin of left coronary artery from pulmonary artery. Wide Q-waves may be noted in the left and lateral precordial leads (I, aVL, V4, V5, and V6). A somewhat similar electrocardiography may be seen in normal children when wrong technique is used in performing electrocardiography. If the right and left limb leads are reversed, Q-waves will be noted in leads I and aVL, however, not V4, V5, and V6. In addition, the P waves assume an abnormal axis with wrong lead placement. Abnormal origin of left main coronary artery from the pulmonary artery is corrected by reimplanting anomalous coronary artery into the aorta, or creating a baffle to direct blood flow from the aortic root to the coronary artery originating from the pulmonary artery (Takeuchi procedure). Abnormal origin of left coronary artery from right coronary sinus can be surgically corrected by widening the opening (unroofing) of left main coronary artery if it is of the intramural type to prevent collapse of orifice when both aorta and pulmonary arteries are distended during exercise.