Rhabdomyomas
Overview
Plain-Language Overview
Rhabdomyomas are rare, benign tumors that develop in the heart muscle. They are most commonly found in infants and young children and can affect the heart's ability to pump blood effectively. These tumors are often associated with a genetic condition called tuberous sclerosis complex, which causes growths in multiple organs. Symptoms may include heart rhythm problems, difficulty breathing, or no symptoms at all if the tumors are small. Diagnosis usually involves imaging tests like echocardiography. Treatment depends on the size and symptoms caused by the tumors, with some cases requiring surgery. Overall, these tumors primarily impact the cardiovascular system and can influence heart function.
Clinical Definition
Rhabdomyomas are the most common primary cardiac tumors in children, characterized by benign hamartomatous growths of striated muscle within the myocardium. They arise due to mutations in the TSC1 or TSC2 genes, leading to dysregulation of the mTOR pathway and abnormal cell proliferation. These tumors are strongly associated with tuberous sclerosis complex, a multisystem genetic disorder. Clinically, rhabdomyomas may cause obstruction of blood flow, arrhythmias, or heart failure depending on their size and location. Histologically, they consist of large polygonal cells with abundant glycogen and characteristic spider cells. Most rhabdomyomas regress spontaneously over time, but their presence is a major diagnostic clue for underlying tuberous sclerosis. Their clinical significance lies in potential hemodynamic compromise and arrhythmogenic risk.