Giant left atrium investigated by magnetic resonance imaging.

A 76-year-old man with a history of chronic mitral regurgitation presented with symptoms of progressive heart failure. The chest radiograph (Fig. 1A) showed severe cardiomegaly (arrows), with a cardiothoracic index (CTI) > 0.7. Echocardiography (Fig. 1B) demonstrated severe biatrial dilatation, severe mitral regurgitation consistent with rheumatic valve disease, and moderate aortic and tricuspid regurgitation. Since the patient refused preoperative coronary angiography, an isotope stress test was requested. The study showed nomyocardial ischemia, but a large photopenic area was seen in the right mediastinum. Cardiac magnetic resonance imaging disclosed a giant left atrium (GLA) with a calculated volume of 2100 mL (Fig. 1C–E) and severe mitral regurgitation