Hypoplastic Right Heart Syndrome (HRHS)

Hypoplastic Right Heart Syndrome (HRHS) [hypo=under, plasia=formation or development, ventricles=lower chambers of the heart]:  the right side of the heart is underdeveloped–including the right ventricle, the pulmonary artery (which carries oxygen-poor blood from the heart to the lungs), and the valves controlling the blood flow of the right ventricle (tricuspid valve, pulmonary valve). These valves may be narrowed (stenosis) or missing (atresia).