[Lipomatous hypertrophy of the interatrial septum is a rare, benign cause of atrial arrhythmia].

Lipomatous hypertrophy of the interatrial septum is a pathological thickening of the interatrial septum characterized by a benign infiltration of fat. It usually occurs in older, obese persons and in most cases the diagnosis is made incidentally. Atrial arrhythmias may occur and in rare cases also superior vena cava syndrome caused by obstruction of venous inflow to the right atrium. We present a case of lipomatous hypertrophy of the interatrial septum in an 81-year-old woman with atrial arrhythmia.