Single Inlet Univentricular Heart with Truncus Arteriosis and Atrial Septal Defect

Abstract

An early neonate with unremarkable antenatal and birth history presented to our hospital on the third postnatal day with cyanosis and features of shock. Differential diagnosis of congenital heart disease and septicaemia were considered. The baby succumbed, despite inotropic and ventilator support, 2½ hours post admission. Necropsy revealed multiple congenital cardiac anomalies comprised of single inlet univentricular heart (UVH),truncus arteriosus (TA) and atrial septal defect (ASD) without heterotaxy or associated anomaly of other organs.Truly (structurally and functionally) Univentricular hearts of indeterminate morphology are exceedingly rare and more commonly a second rudimentary or hypoplastic accessory ventricle is present. Occurrence of UVH together with rare and distinct defect like truncus arteriosus and atrial septal defect which have different embryogenesis is exceptional. UVH and TA are both total mixing lesions with total admixture of pulmonary and systemic venous return and as pulmonary vascular resistance drops in the early neonatal period the pulmonary blood flow, in the setting of unobstructed pulmonary out flow, markedly increases leading to cardiac failure finally culminating in death.Prenatal diagnosis of CHD’s is possible by fetal echocardiography with a high degree of accuracy and termination of pregnancy can be an option for CHD’s associated with a dismal outcome.