Giant right atrial diverticulum in an adult.

We describe a 32-year-old man with chest pain and a giant right atrial diverticulum who underwent surgical resection. Examination of resected atrial tissue showed extreme wall thinning, central aneurysmal formation, and focal endocardial fibrosis consistent with idiopathic dilatation of the right atrium. It is unclear what the best treatment of right atrial diverticulum are, nor are the risks of thromboembolism, arrhythmia, and rupture of the diverticulum clearly defined, either for patients as a whole or for symptomatic or asymptomatic subgroups. However, to reduce the risk of sudden death we recommend surgical resection of large diverticula.