Spontaneous regression of a large rhabdomyoma of the interventricular septum.

We report the case of a large congenital rhabdomyoma of the interventricular septum diagnosed prenatally. The foetus was strictly monitored with ultrasound throughout the gestation period showing that the mass had increased in size until delivery. Despite the size of the mass, which appeared to occupy the right ventricle, the baby presented no symptoms both in utero and after birth. Serial echocardiography was used to document the regression of the mass in childhood.