Isolated congenital right ventricular hypoplasia is a very rare cardiopathy. Its incidence has never been truly established. However, statistically it should be inferior to 1/200,000. It can occur in many complex congenital heart defects. Rare familial cases have been reported. Hypoplasia of the inlet and trabecular components of the right ventricle is rarely the most conspicuous finding. The right outflow tract is usually widely patent or minimally narrowed without obstruction. Patients present mostly with cyanosis due to right-to-left shunting through an atrial septal defect. Age at presentation may vary from neonatal period to adulhood. Reduced tricuspid valve annulus with a variable degree of tricuspid stenosis is frequently noticed with right ventricular hypoplasia. Together with a reduced compliance of the right ventricle, tricuspid hypoplasia contributes to right-to-left shunting at atrial level. Diagnosis is performed by echocardiography. Assessment of the tricuspid valve anatomy and function is fundamental to define the therapeutic strategies. The left ventricle is usually normal. Angiocardiography is necessary to define the nature of the systemic venous connections. Indeed, when cyanosis is significant, bidirectionnal cavopulmonary connection combined with closure of the atrial septal defect (1.5 ventricle repair) can be proposed. To date, no particular genetic syndrome has been observed in close association with isolated right ventricular hypoplasia.
Last update: June 2003