Comparison of Two Different Methods of obtaining Strain by Perioperative Transesophageal Echocardiography in Patients undergoing Coronary Artery Bypass Graft Surgery: A Prospective Observational Study

Abstract

Introduction: Tissue deformation imaging enables the objective assessment of regional myocardial deformation assessed by ultrasound-based strain and strain rate. There are two ways to compute myocardial deformation (strain) using echocardiography: One-dimensional tissue Doppler (DTI)-derived strain and two-dimensional (2D) strain derived from B-mode images (speckle tracking, 2D-ST). This study compares the myocardial deformation parameter (i.e., strain) by these two techniques in the perioperative period using transesophageal echocardiography (TEE) in patients undergoing surgery for coronary artery bypass graft (CABG). Materials and methods:We performed preoperative global longitudinal strain (GLS) of left ventricle (LV) using 2D-ST and DTI, three-dimensional (3D) left ventricular ejection fraction (LVEF) and 2D LVEF in a consecutive series of 50 adult patients scheduled for on-pump CABG.Result: There was no difference between 2D and 3D LVEF (p < 0.0001), GLS using 2D-ST and DTI (p-value = 0.0005). The 3D LVEF correlated well with GLS using 2D-ST (r = 0.54, p < 0.0001) and less with tissue Doppler-derived GLS (r = 0.35, p-value = 0.0131). Conclusion:The LV GLS calculated using 2D-ST correlates well with LV GLS derived from DTI using TEE. The LV GLS also correlated well with the 3D LVEF.

Strain Measurements in Perioperative Settings

“…Although there are certain limitations of TDI strain, they can be a valuable noninvasive tool for routine clinical use in certain specific scenarios. Kumar et al 3 in first of its kind study have very meticulously tried to compare the TDI strain and the speckle tracking strain. Although speckle tracking is more convenient and a robust measure of LV strain but in conditions where, it is difficult to view the entire wall of LV, GLS becomes difficult to compute.…”