Contrast transesophageal echocardiography in diagnosing congenital enlargement of the right atrium--a case report.

Congenital malformation of the right atrium or the coronary sinus is rare, and cases are classified into 1 of the following 4 categories: (1) congenital enlargement of right atrium, (2) single diverticulum, (3) multiple diverticula of the right atrium, and (4) diverticulum of the coronary sinus. This report presents a 63-year-old man with cardiomegaly and no chest symptoms. A chest radiograph revealed an enlarged cardiac silhouette with a prominent right heart border. Although a transesophageal echocardiography revealed marked enlargement of the right atrium, neither further anomaly nor massive regurgitation was observed. The systolic pulmonary artery pressure derived from the peak velocity of mild tricuspid regurgitation was 38 mm Hg. Secondary enlargement of the right atrium due to atrial septal defect or pulmonary venous connection anomaly was deemed negligible by use of transesophageal contrast echocardiography, and primary enlargement of the right atrium was confirmed. Transesophageal echocardiography using ultrasound contrast was determined to be feasible for diagnosing congenital malformation of the right atrium.