Huge pericardial rhabdomyoma with hypoplastic left ventricle and lung.

We describe the clinical course and autopsy findings of a female fetus with hydrops fetalis due to a huge pericardial rhabdomyoma. Fetal echocardiography at 21 weeks gestation demonstrated a huge tumor in the left ventricle. The fetus died of hydrops fetalis due to cardiac dysfunction at 24 weeks gestation. Autopsy demonstrated that the tumor protruded from the epicardial region of the apex into the pericardial cavity and induced a hypoplastic left ventricle and lung. Microscopically, the cardiac tumor showed characteristics of rhabdomyoma. This localization of cardiac rhabdomyoma is rare, but we remain aware of the possibility of an unusual and rapid progression of cardiac rhabdomyoma.