TRANSESOPHAGEAL MULTIPLANE IMAGING OF THE HUMAN PULMONARY-ARTERY - A COMPARISON OF MRI AND MULTIPLANE TRANSESOPHAGEAL 2-DIMENSIONAL ECHOCARDIOGRAPHY

Objective: To evaluate the anatomical relationship between the esophag us and pulmonary artery including assessment of the correct transesoph ageal Doppler insonation angle into the mid-pulmonary artery trunk. Me thods: We evaluated the anatomical relationship between the esophagus and pulmonary artery (PA) from comparable magnetic resonance (MR) and transesophageal echocardiographic (TEE) multiple two-dimensional image s (0 degrees, 45 degrees, 90 degrees and 135 degrees clockwise rotatio n of the standard transverse scanning plane when seen from the esophag us) obtained in 10 healthy, young volunteers. Results: The main PA cou ld be visualized with both techniques in all 10 volunteers and provide d highly identical images of good quality. A mean insonation angle of 35 degrees (range 26 degrees-46 degrees) for a fictive esophageal Dopp ler beam into the main PA was disclosed. The PA trunk was short with a mean length of 23.4 mm (range 17-30 mm). Conclusions: These anatomica l data contradict the general assumption of alignment of the pulmonary artery and the transesophageal Doppler beam. Angle correction should be applied in the clinical setting using MTEE by rotation of the scann ing plane to approximately 45 degrees. Ignoring the insonation angle o f approximately 35 degrees may cause 20% underestimation of blood flow velocity and cardiac output in the PA. (C) 1997 Elsevier Science B.V.