[Idiopathic enlargement of the right atrium with persistent superior vena cava].

A 69-year-old male, who had been found (during a routine roentgenogram of the chest at an annual check-up) to have cardiomegaly, had been asymptomatic until 63 years of age, when DOE and swelling of the legs appeared. He visited our hospital because these symptoms has become more severe. Physical examination revealed JVD, third heart sound and a grade 3 holosystolic murmur, hepatomegaly and edema in the lower legs. His ECG showed atrial fibrillation. His chest X-P showed marked cardiomegaly and rt pleural effusion. His echocardiography and MRI revealed a marked enlargement of the right atrium and a slight enlargement of the right ventricle. The latter also showed persistent left superior vena cava. The cardiac catheterization, angiocardiography and intracavitary electrocardiography revealed no organic cardiac disease which induced enlargement of the right atrium. The idiopathic enlargement of the right atrium is a rare disease. Patients suffering from this disease are asymptomatic in most cases. We reported the idiopathic enlargement of the right atrium with persistent left superior vena cava in this paper.