Mekhtieva F.B. Optimization of treatment of patients with coronary heart disease after revascularization based on the study of myocardial dyssynchrony. Qualification scientific work in the form of a manuscript. The dissertation is devoted to the optimization of management of patients with coronary heart disease undergoing coronary artery revascularization by assessing the presence and degree of mechanical myocardial dyssynchrony in order to identify high-risk patients in whom revascularization gives the maximum effect and predict the further course of coronary heart disease, the development of adverse cardiovascular events and chronic heart failure.
To achieve the set goal, 134 patients were included in the study, of whom 105 were men (78.4%) and 29 were women (21.6%) at the age of 56.2+9.7 years. 64.1% of patients were diagnosed with arterial hypertension, 56.7% had chronic heart failure, and 44.0% had concomitant type 2 diabetes mellitus. Patients were divided into 4 comparison groups depending on the number of affected CAs according to coronary angiography data: the first group included 26 patients in whom no CA lesions were detected, the second group included 35 patients in whom atherosclerotic lesions of one CA were detected (median SYNTAX SCORE 2.00 (0 - 18; 95% CI 0.562 - 3.44), the third group included 29 patients with lesions of 2 CAs (median SYNTAX SCORE 5.00 (0 - 27; 95% CI 0.655 - 9.35) and the fourth group included 44 patients with lesions of 3 CAs (median SYNTAX SCORE 8.00 (2 - 25; 95% CI 5.361 - 10.64). All patients before coronary angiography determined the parameters of mechanical DM: SPWMD (left ventricular posterolateral wall activation delay), APEI (aortic transit time, PPEI (pulmonary artery transit time), IVMD (interventricular mechanical delay) which includes recording of the LV outflow tract (apical 5-chamber view) and the RV outflow tract (parasternal short-axis view of the great vessels) and calculating the difference in time between the beginning of the Q wave on the ECG and the beginning of LV outflow and the time between the beginning of Q and the beginning of RV outflow, LVFT (left ventricular filling time), LVET (left ventricular ejection time), IVRT (LV isovolumic relaxation time), DT (time of slowing the flow of early ventricular filling), To (time from the beginning of the QRS complex to the beginning of the peak systolic velocity), To-SD (standard deviation of time to the onset of LV systolic velocity), Ts (time to peak systolic velocity), Ts-SD standard deviation of time to peak systolic velocity - (Yu index) using ultrasound examination of the heart on the SiemensAcUSONSC 2000 device, (USA) according to international recommendations of the American Society of Echocardiography and the European Association of Cardiovascular Imaging using a sensor from 3.5 to 7 MHz. The following were used: M-mode, 2D-mode, pulsed-wave and tissue Doppler according to the generally accepted methodology. Echo-CG was synchronized with ECG registration in four cardiac cycles from standard accesses.
Scientific novelty of the obtained results. The frequency of detection of mechanical myocardial dyssynchrony is significantly higher in patients with coronary heart disease compared to patients without CAD who underwent revascularization (41.3% vs. 6.2%, respectively). It was shown for the first time that patients with CAD with 3-vessel disease who underwent revascularization had a significantly higher frequency of detection of DM (52%) compared to patients without disease and with 1 or 2 CVDs. The indices of intraventricular (Ts), interventricular (IVMD) and atrioventricular (LVFT) DM were associated with 3-vessel disease and SYNTAX SCORE. The combination of DM indices in terms of predicting 3-vessel CA disease has sufficient sensitivity and specificity, which creates prospects for its application in clinical practice.
For the first time, a significant increase in the frequency of mechanical dyssynchrony of the LV myocardium was found in patients with ischemic heart disease who underwent revascularization with complete occlusion of the CA. With incomplete occlusion of the CA, the frequency of DM did not differ significantly in comparison with patients with unchanged CA and patients with atherosclerotic lesions of the CA without occlusion. It was shown for the first time that after revascularization, the number of patients with DM decreased by 18%.
Practical significance of the results obtained.The combination of myocardial dyssynchrony indicators in terms of predicting 3-vessel coronary artery disease has sufficient sensitivity (0.89) and specificity (0.87), which creates prospects for its application in clinical practice. Determination of APEI, LVFT and LVET DM indicators allows for the selection of patients with high-risk IXC in whom coronary artery revascularization gives the greatest result.
