Pitfalls in the echocardiographic diagnosis of aortic dissection.

The authors studied 25 patients with transthoracic echocardiography (TTE) and/or transesophageal echocardiography (TEE) for suspected aortic dissection. Of these, aortic dissection was diagnosed correctly in 19 patients, but in 6 the echocardiographic findings for dissection were atypical or false-positive. In patient 1, the TEE revealed a dilatated proximal aortic root. TEE showed a possible flap but was nondiagnostic. The diagnosis was made by computed tomography (CT) and confirmed at surgery to be type 1 dissection. In patient 2, the TTE depicted flail aortic cusps, questionable vegetations, and dilatated aortic root. In patient 3, TTE demonstrated moderate pericardial effusion with hematoma but no dissection. Type 1 dissection was subsequently confirmed at autopsy in both. Patient 4 had TEE diagnosis of type 3 dissection. However, reevaluation of the study by a senior sonographer just prior to surgery led to the correct diagnosis of type 1 dissection. Patients 5 and 6 had dilatated ascending aortas with linear echoes within the lumen on TEE and were reported as having type 1 dissections. CT and/or angiography did not reveal dissection in either patient. In conclusion, TTE and TEE are vaulable tests in diagnosing aortic dissection. However, atypical features, misdiagnosis of the site of dissection, or false-positive studies can occur.