Lipomatous Hypertrophy of the Interatrial Septum - A Case Report -

Lipomatous hypertrophy of the interatrial septum is a benign cardiac mass that is characterized by excessive deposition of fat in the interatrial septum. It typically occurs in elderly, obese patients and may cause arrhythmia. We report a case of lipomatous hypertrophy of the interatrial septum. A 45-year-old man was admitted for evaluation of chest discomfort. Transthoracic echocardiography revealed a cardiac mass, which was suspected as a myxoma. A resection of the tumor was performed. Grossly, the mass was 1.3 x 1.2 x 0.8 cm, and showed yellow soft consistency and good demarcation. Microscopically, the mass consisted of mature adipose tissue, intermixed cardiac muscle fibers, entrapped nerve fibers and ganglion cells. Lipomatous hypertrophy of the interatrial septum should be differentiated pathologically from tumorous cardiac mass such as lipoma and myxoma.