Linear Reverberation in the Ascending Aorta: A Cause of Multiplane Transesophageal Echocardiographic Artifact

To the Editor:-Reverberations are important potential echocardiographic artifacts commonly encountered during imaging of the thoracic aorta because of the presence of smooth, highly reflective tissue-fluid and tissue-air interfaces. Linear artifacts in the ascending aorta, which may mimic intimal flaps, were seen in 44% of patients with a monoplane transesophageal echocardiography (TEE) and in 35% of patients with a biplane TEE in series published by Appelbe and co-workers. [1]These artifacts were associated mainly with dilation of the ascending aorta. It was proposed that multiplane TEE might be useful to provide additional views and improved diagnostic accuracy of aortic dissection. [2]We present a case of reverberation artifact mimicking an aortic root dissection with a multiplane TEE probe. A 55-yr-old man was admitted after a road accident. Initial evaluation demonstrated intracranial trauma and multiple extremity and rib fractures. In the emergency unit, hemodynamic stabilization required volume loading and initiation of inotropic support. The patient was transferred to the operating room for treatment of his extremity fractures. Because of hemodynamic instability, it was decided to initiate intraoperative TEE monitoring. Systematic examination performed with a multiplane 5-MHz probe revealed the presence of a linear structure in the proximal ascending aorta in the transverse and longitudinal planes (Figure 1) resembling an intimal flap and suggesting an aortic root dissection. Diagnosis was critical in the context of chest trauma but obvious after careful echocardiographic examination by obtaining images from different incidences. The linear structure had indistinct borders, did not display rapid oscillatory motion, was parallel to the posterior aortic wall (PAW), and was located at twice the distance from the right pulmonary artery posterior wall (RPPAW) as from the PAW. This artifact could be generated when the echo of the PAW is bounced back from the transducer or could correspond to a reverberation from a moving target, the RPPAW, and a moving mirror, the PAW, as recently described by Evangelista and coworkers. [3]In addition, color Doppler did not show interruption of the flow pattern and assisted the differential diagnosis between an artifact and an intimal flap. This case illustrates the possibility of artifact in the ascending aorta with multiplane TEE and the necessity of defined echocardiographic training to avoid erroneous diagnosis and recognize pitfalls with TEE. (Figure 1)

Anne R. Ducart, M.D., Serge M. Broka, M.D., Edith L. Collard, M.D., Service d' Anethesiologie, Cliniques Universitaires de Mont-Godinne, B-5530 YVOIR, Belgium.

(Accepted for publication September 12, 1996.)