The rate of myocardial contraction in the assessment of diastolic function

Objective : to evaluate the results of biomechanics of myocardial contraction during diastole in patients with coronary heart disease based on the results of vector analysis MATERIAL : the study is based on 79 patients with coronary heart disease with myocardial infarction and scarring of the heart muscle aged 53±4 years and 34 healthy volunteers — 41±3 years were examined. Before and after the operation of coronary artery bypass grafting, transthoracic echocardiography was performed, followed by computer image processing and calculation of hemodynamic parameters — EDV, ESV, EF, E\A. Vector analysis was used to estimate the rate of myocardial displacement (V), from the apex to the basal region in six regions of the left ventricle. RESULTS . To determine the mechanical characteristics of left ventricular (LV) contraction, a method was used that allows dynamic series of ultrasound images to track the rate of myocardial contraction in the basal, middle and apical parts of the heart. Before surgery, during diastole, the rate of myocardial contraction increased by more than 30% in comparison with the norm in the basal, middle, and apical regions. Changes occur due to a decrease in myocardial perfusion. In response, hyperfunction occurs, which leads to the activity of additional cardiomyocytes in maintaining heart performance. After the operation, the recovery of myocardial contraction rates to normal values was noted. CONCLUSION . The results showed the dynamics of the rates of myocardial displacement mainly in the diastole, but there is no complete recovery in the hospital period. Diagnosis of the mechanical function of the myocardium during the cardiac cycle is based on the dynamics of the rates of contraction from the apex to the basal part of the left ventricle. Evaluation of the activity of myocardial contraction has certain advantages in determining the state of diastolic function of the left ventricle.