Cardiac interventions in the fetus: Potential for right-sided lesions. Fetal interventions in right heart disease

Abstract

Numerous studies have shown progression of heart disease in utero. Fetal cardiac interventions were first performed in left heart disease, but right heart defects also deserve attention. Pulmonary atresia with intact ventricular septum is a lesion with high mortality and morbidity. It can evolve from critical pulmonary stenosis and result in failure of ventricular growth. Postnatally biventricular repair can be achieved only in 32% to 60%. Therefore, if critical stenosis or membranous atresia of the pulmonary valve can be opened early enough before birth, one could speculate that outcome may improve. Fetal intervention may reverse pulmonary atresia, thus improving growth of the tricuspid valve and the right ventricle. Reduction in right ventricular pressure may prevent continuing damage to the myocardium, resulting in improved mortality and morbidity and a better chance for biventricular repair with less potential for late complications. Successful intracardiac interventions have already been performed in 5 fetuses with pulmonary atresia with intact septum. These cases have demonstrated that interventions in this lesion are feasible, can cause improvements in fetal hemodynamics and may affect outcome. Other right heart lesions that might become targets for future interventional procedures are pulmonary atresia with ventricular septal defect and aorto-pulmonary collateral arteries and Ebstein's anomaly with severe tricuspid regurgitation.