Aortopulmonary (AP) window is exactly a rare congenital anomaly that represents approximately 0.2 and 0.5% of all congenital heart abnormalities. It consists of communication between the aorta and the pulmonary artery or its branches. Although closely related to AP window, the pulmonary artery origin from the ascending aorta (also termed “hemitruncus”) is classified as a separate defect. AP window was first described by Elliotson in 1830 in an autopsy study. In 1948, Robert Gross successfully ligated an AP window in a patient undergoing a thoracotomy for closure of a patent ductus arteriosus (PDA). In 1957, Cooley and associates described the first successful repair of AP window using cardiopulmonary bypass. Aortopulmonary window occurs due to the abnormal development of the heart’s major blood vessels during early fetal growth. In most cases, this heart defect occurs by chance, with no clear reason. This condition can occur on its own or with other heart defects such as: 1. Tetralogy of Fallot, 2. Pulmonary atresia, 3. Truncus arteriosus, 4. Atrial septal defect, 5. Patent ductus arteriosus, 6. Interrupted aortic arch. Treatment for aortopulmonary window involves surgery to close the hole between the aorta and the pulmonary artery with a patch or device. This surgery is normally done as soon as possible after the diagnosis is made, usually when the child is a newborn. Associated lesions are usually repaired during the same surgery. Associated lesions are usually repaired during the same surgery. More complex repairs and myocardial protection strategies are required in patients with associated lesions, increasing the morbidity and mortality associated with the operation.