[Endocardial Blood Cyst in the Right Atrium:Report of a Case].

A 74-years-old man visited our hospital complaining chest discomfort, and he was diagnosed with variant angina. However, during close examination, a tumor with some small calcified nodules was accidentally pointed out in the right atrium. We carried out surgical removal to prevent embolism. A cystic tumor attached to the atrial septum was resected together with the atrial septum, and the defect was closed with a Dacron patch. The tumor size was 18×25×3 mm. Histologically, its wall was consisted of connective tissue, which was positive for CD34, negative for calretinin, and was diagnosed as an endocardial blood cyst. A core of the nodules in the cyst were calcified and they were phleboliths. Postoperative echocardiography detected no residual mass or atrial septal defect, and he was discharged uneventfully.