Evaluation of Left Ventricular Longitudinal, Radial, and Circumferential Strains in Subjects with Normal Variations...

The aim of this study was to evaluate the contractile function of the left ventricular muscles in subjects with normal coronary artery and normal variations of coronary dominance.

This study was performed on 90 adult subjects with normal results of coronary arteries angiography, echocardiography, and electrocardiography. The participants were categorized into 3 groups of 30 with right-dominant, left-dominant, and codominant variations. Two-dimensional transthoracic echocardiography was performed with apical 2-, 3-, and 4-chamber views and parasternal basal, mid, and apical short-axis views. Then, images were analyzed offline using the velocity vector imaging method. In all studied groups, the mean and standard deviation of left ventricle coronary territorial longitudinal, circumferential, radial strains, and left ventricle global strains were determined. They were compared in 3 layers of sub-endocardial, myocardium, and sub-epicardial.

In terms of longitudinal and circumferential strains, there were significant differences in the most coronary territories and global strain among the right-dominant, left-dominant and codominant groups (P < .05). No significant differences in terms of territorial and global radial strains were observed among the study groups (P > .05).

Strain level decreased from endocardium to epicardium in all studied groups. Territorial and global contractile functions (longitudinal and circumferential strains) of the left ventricle vary depending on the variations of coronary arteries.