Systolic longitudinal strain and congestive heart failure in patients with moderate ischemic mitral insufficiency before and after surgical revascularization and mitral annuloplasty

Objectives. The aim of this study was to evaluate the longitudinal systolic deformation indicators and the dynamics of chronic heart failure (HF) symptoms in patients before and after surgical revascularization and repair of ischemic mitral insufficiency. Methods. We studied 65 patients after a myocardial infarction and a moderate degree of ischemic mitral regurgitation. The patients were divided into 2 groups: in the first group (n = 35) we performed isolated surgical revascularization (3.9±0.9 distal anastomosis), while the second group patients (n = 31) underwent combined coronary artery bypass grafting (3.6±1.3 distal anastomosis) and mitral annuloplasty. Before and after the operation (an average of 12 months after surgery) we evaluated the symptoms of heart failure, conventional ECG data, the indicators of systolic left ventricle (LV) longitudinal deformation and its rate (measured by using speckle-tracking 2-dimensional echocardiography). To obtain control ECG indicators, 25 healthy individuals were examined. Results. Significant increases of the longitudinal systolic strain (before operation -6.7±2.9 %, after -8.7±3.8%, p=0.024) and strain rate (before operation -0.67±0.22 sec 1, after -0.77±0.21 sec 1, p=0.004) were observed only in the second group patients (combined surgical revascularization and mitral annuloplasty). Our results confirm that longitudinal systolic deformation is an objective quantitative indicator of left ventricular systolic function in patients with mitral insufficiency and an independent predictor of postoperative HF: GLPS -9.7±1.9% (±95% CI from -9 to -10.4) associated with a decrease of functional class HF, GLPS -3.4±0.8 % (±95% CI from -2.6 to -4.2) related with an increase of postoperative HF (β=-0.9, RI=0.86). Conclusions. In patients with moderate mitral regurgitation, the longitudinal myocardial strain and strain rate reflect a mechanical function of the left ventricle and predict heart failure after surgical revascularization.