Abstract
We report a fatal case of myocardial ischemia in a 1-month-old infant caused by a hypoplastic left coronary cusp, a rare, congenital anomaly. The infant presented with acute respiratory failure and hemodynamic instability. Transpericardial echocardiography revealed occlusion of the left coronary ostium by a hypoplastic left cusp. Despite emergency aortic valvuloplasty, refractory cardiogenic shock developed, resulting in death. The present case highlights the importance of considering hypoplastic coronary cusp in the differential diagnosis of infantile myocardial ischemia and the need for careful echocardiographic evaluation of suspected cases. LEARNING OBJECTIVE: Hypoplastic aortic valve cusp should be borne in mind as a potential cause of myocardial ischemia in children.Meticulous echocardiographic assessment should be performed for any coronary artery of anomalous origin and for the morphology of the aortic valve cusp.