Effect of Position Changes on Myocardial Velocity in Healthy Subjects Evaluated by Tissue Doppler Echocardiography*

Objectives: This study designed to assess the effect of different positions of head of the bed on myocardial velocity by tissue Doppler echocardiography in healthy subjects. Methods: Thirty-nine healthy subjects (32 males/7 females, mean age 24.7 ± 4.9 years) were studied. Tissue Doppler imaging (TDI) was performed and velocities were recorded during systole (Sm) and early (Em) and late (Am) diastole at the tricuspid annulus, septum, and mitral annulus in the four-chamber view. Measurements were performed from different positions of left lateral decubitus (0°, 30°, and 60°). Repeated-measures general linear models were used to assess the change in myocardial velocities. Results: No significant difference between myocardial velocities was found at the mitral anulus and septal TDI recordings in the different angles of left lateral decubitus positions (P > 0.05). However, there were statistically significant difference among tricuspid anulus myocardial tissue velocities in these positions (P < 0.05). Conclusions: Tricuspid anulus myocardial tissue velocities may be significantly influenced by changing of position in healthy subjects. Effect of position changes should be considered in the assessment of these velocities. (Echocardiography 2011;28:516-519)