A rare case of congenital aneurysm of the right atrium

We report the case of a 58-year-old hypertensive man referred for a cardiology consultation due to atypical chest pain. The clinical examination was unremarkable. An electrocardiogram demonstrated sinus rhythm and incomplete right bundle branch block. He had an ambulatory echocardiogram that was described as normal. An exercise test was negative for ischemia and showed intermittent complete right bundle branch block. To exclude coronary disease a contrast computed tomography (CT) scan was performed that revealed a saccular aneurysm of the lateral free wall of the right atrium measuring 45 mm×45 mm×43 mm (Figures 1 and 2). There was no evidence of coronary disease. Given the CT findings, transthoracic echocardiography was repeated and revealed a cystic, pulsatile structure in continuity with the free wall of the right atrium through a narrow neck (Figure 3) permitting low-speed two-way flow, subsequently confirmed by injection of Sonovue contrast. No cardiac thrombi were visualized. The tricuspid valvular apparatus and right ventricle were morphologically normal, as was biventricular systolic function. Similar findings were visualized on the transesophageal echocardiogram.