Unguarded left atrioventricular orifice: An unusual cause of hypoplastic left ventricle and double-outlet right ventricle with intact ventricular septum

An unguarded atrioventricular orifice is an extremely rare congenital anomaly characterized by the absence of the atrioventricular valve in varying proportions. While atresia of the mitral or aortic valves are usually described as causes for hypoplastic left heart, our case highlights the role of free atrioventricular valve regurgitation and consequent volume loss of the left heart, giving rise to a small left ventricle. There was an associated double-outlet right ventricle and Type B aortic interruption. While we have attempted to discuss the complex management options in this scenario, the parents decided to withdraw further care.