Aortic sinus aneurysm rupture into the right atrium in a 29-year-old patient.

A 29-year-old man presented with chest tightness and shortness of breath. Physical examination showed jugular venous distention. Echocardiography showed a large saccular anechoic structure in the right atrium, swinging with the cardiac cycle. The operator initially mistook the lesion for a right atrial cystic tumor; however, color Doppler imaging showed abundant, high-velocity blood flow signals, leading to the diagnosis of giant aortic sinus rupture into the right atrium. Aortic sinus aneurysm is a rare and usually asymptomatic lesion. However, rupture leads to chest tightness and dyspnea, suggesting left or right heart failure. Surgery is the primary treatment.