Transesophageal multiplane imaging of the human pulmonary artery: a comparison of MRI and multiplane transesophageal two-dimensional echocardiography.
OBJECTIVE
To evaluate the anatomical relationship between the esophagus and pulmonary artery including assessment of the correct transesophageal Doppler insonation angle into the mid-pulmonary artery trunk.


METHODS
We evaluated the anatomical relationship between the esophagus and pulmonary artery (PA) from comparable magnetic resonance (MR) and transesophageal echocardiographic (TEE) multiple two-dimensional images (0 degree, 45 degrees, 90 degrees and 135 degrees clockwise rotation of the standard transverse scanning plane when seen bearfrom the esophagus) obtained in 10 healthy, young volunteers.


RESULTS
The main PA could be visualized with both techniques in all 10 volunteers and provided highly identical images of good quality. A mean insonation angle of 35 degrees (range 26 degrees-46 degrees) for a fictive esophageal Doppler 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 anatomical 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 scanning plane to approximately 45 degrees. Ignoring the insonation angle of approximately 35 degrees may cause 20% underestimation of blood flow velocity and cardiac output in the PA.
Sloth
E
E
Dept. of Anaesthesia, Skejby Sygehus, Aarhus University Hospital, Denmark.
Pedersen
E M
EM
Egeblad
H
H
Hasenkam
J M
JM
Juhl
B
B
D000328:Adult; D017548:Echocardiography, Transesophageal; D004947:Esophagus / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D011651:Pulmonary Artery / Q000033:anatomy & histology* / Q000000981:diagnostic imaging