A case of chronic dissecting aortic aneurysm complicated with rupture into the right atrium: Diagnosis by transesophageal echocardiography

Although rupture of a dissecting aortic aneurysm into the pericardial sac, pleural cavities, or mediastinum is a frequently encountered complication of this entity, rupture into a right-sided cardiac chamber is extremely rare. An 80-year-old woman was admitted to this institution because of dyspnea and facial edema. One year before admission, a diagnosis of dissecting aortic aneurysm (Stanford A type) was made based on results of magnetic resonance imaging and transesophageal echocardiography (TEE); however, the patient and her family refused surgical therapy. On admission, blood pressure was 120/60 mmHg, and a Levine 3/6° continuous murmur was audible at the third and fourth intercostal spaces of the right sternal border. Chest x-ray film showed moderate cardiomegaly, congested lung fields, and bilateral pleural effusion. A two-dimensional echocardiogram revealed severe aortic root dilatation 80 mm in diameter with the intimal flap. Color flow Doppler imaging demonstrated abnormal flow toward the back space in dilated ascending aorta. Continuous wave Doppler imaging showed the peak velocity of this flow to be 4.8 m/s. This high-velocity flow strongly suggested that the dissecting aortic aneurysm had ruptured into the right-sided cardiac chamber, and shunt flow from the false lumen of the aortic aneurysm into the right atrium was directly visualized by TEE. Our diagnosis, based on these findings, was chronic dissecting aortic aneurysm with communication into the right atrium. In view of the patient’s deteriorating clinical condition, cardiac catheterization was not performed before surgery. Surgery revealed an aneurysm of the ascending aorta measuring 90 mm in diameter and multiple fistulas approximately 2 to 3 mm in diameter arising from the false lumen of the aorta into the right atrium at the base of the atrial appendage. The patient underwent successful replacement of the ascending aorta and closure of the aorto-right atrial fistulas. She had an uneventful postoperative course and was discharged 7 weeks after surgery.