Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital cardiovascular defect that occurs in approximately 1/300 000 live births or 0.5% of children with congenital heart disease. The mortality of untreated ALCAPA has been estimated to range from 35% to greater than 85% in the first year of life. However, in some cases patients can survive past infancy and into adulthood and do not present with symptoms until later in life. These older patients often manifest their anomalies as congestive heart failure, malignant arrhythmias, or even sudden death. We report a series of 3 cases from our institution illustrating the various late presentations of this unusual diagnosis. We review the pathophysiology of this rare congenital anomaly and discuss some of the signs, symptoms, and diagnostic tests that can help diagnose this unusual condition in adults.