Assessment of left ventricular regional function after coronary artery bypass grafting by strain rate imaging

Abstract

Objective To investigate the value of strain rate imaging(SRI) in estimating the changes of left ventricular regional myocardial function in patients with coronary artery disease before and after coronary artery bypass grafting operation. Methods In sixteen patients with coronary artery disease, echoeardiography was performed 3 days before, 12 days after and 3 months after coronary artery bypass grafting operation respectively. SRI was used to quantitatively analyze the regional myocardial function of left ventricular wall. One hundred and ninety-two segments of left ventricular myocardium were analyzed in the study. The left ventricular myocardium was divided into segments with normal(152 segments) and abnormal(40 segments) wall motion according to two-dimensional echocardiography before the operation. Results Peak strain rate during systolic and early diastolic contraction (SRs, SRe) was not statistically significant between segments with normal and abnormal wall motion before operation. In segments with abnormal wall motion,myocardial peak strain rate of atrial contraction (SRa) was increased three months after operation comparing with three days before operation (P<0.05). In segments with normal wall motion,the absolute values of SRs,SRa and SRe were increased three months after operation comparing with three days before operation (P<0.05 and 0.01 ). SRs was increased three months after operation comparing with 12 days after operation (P<0.05 ). Conclusions SRI can be used to evaluate the functional changes of left ventricular regional myocardium quantitatively after coronary artery bypass grafting operation. Key words: Echocardiography; Ventrieular function, left; Coronary disease; Coronary artery bypass grafting;  Strain rate imaging