Thesis is devoted to optimizing the diagnosis and treatment of acute forms of coronary heart disease (CHD) by means of studying the characteristics of its clinical duration and risk factors, the dynamics of the ECG and EchoCG parameters, as well as ultrastructural changes in cardiomyocytes (CMC), depending on the presence of hibernated (viable) or irreversibly damaged (non-viable) myocardium. The analysis of the clinical examination and instrumental tests of 173 patients with acute coronary syndrome (ACS), including 114 patients with acute myocardial infarction (MI) with and without ST-segment elevation and 59 patients with unstable angina (UA) on the background of postinfarction cardiosclerosis (PICS) in comparison with ultrastructural study (12 myocardial express necropsy from patients who died of myocardial infarction) was performed. Patients with UA in both groups received ivabradine 5 mg twice daily. It was established that reduction of myocardial contractility reserves in patients with ACS is associated with higher number of risk factors for coronary heart disease, in particular the presence of arterial hypertension (AH), diabetes mellitus, type 2 (DM) and work in occupational hazardous conditions. More pronounced manifestation and longer duration of the latter contribute to irreversible myocardial injury in patients with MI with elevation and without ST segment elevation, as well as in patients with UA. Atypical pain syndrome and severe complications of ACS are more common for concomitant comorbidities (AH, DM, occupational hazards), which are contributing to the irreversible myocardial injury. With the development of myocardial infarction and in UA against the background of PICS in patients with non-viable myocardial, unlike patients with hibernating myocardium, significantly higher incidence of complications, mostly cardiac arrhythmias, acute and chronic aneurysm of the left ventricle (LV) and acute heart failure (HF) is observed. It was revealed that ECG criteria for myocardial hibernation in patients with acute myocardial infarction with or without ST segment elevation is a positive 21-day dynamic of ECG parameters (reflecting the decrease in lesion area), which is manifested by a decrease in the depth of pathological Q and QS waves, increase of R wave and reversal of negative T wave. In patients with UA against the background of PICS such ECG criteria was a reliable 14-day positive dynamics of negative T waves. Evaluation of the standard echocardiographic parameters (metric as well as volumetric) and LV ejection fraction (EF) in patients with ACS does not provide complete information on the presence of hibernated myocardium and restoration of its contractile ability. The most informative echocardiographic parameters for the detection of myocardial hibernation are calculation of indices of regional left ventricular contractility such as the degree of violation of local contractility (DLC) and the wall motion score index (WMSI), which enables to determine potential reserves of CMC contractility. In patients with myocardial infarction with signs of hibernation DLC was reduced by 29.00% and 19.67% on the Indus, and in individuals with irreversible injured myocardium it had increased by 5.20% and 1.76%. In patients with UA it had decreased respectively by 12.00% and 6.70% in patients with hibernated myocardium and increased by 14.30% and 7.50% in patients with non-viable myocardium. According to the data of ultrastructural studies of express necropsies from periinfarct and intact ventricular LV myocardial areas of patients who died due to acute myocardial infarction, 5 variants of damaged and dead CMC are present in various proportions (hypertrophied, hibernated, stunned, changed as the result of necrosis or apoptosis). In hypokinetic LV myocardium with signs of hypertrophy, overload and ST segment depression there is a largest proportion of hypertrophic and hibernated CMC - 45-55%, as well as stunned (10-30%), the remain - apoptotic (?20%) and necrotic altered cells (10%). In the LV myocardium in infarction areas and zones of akinesia altered necrotic and (50-55%) and apoptotic (30-35%) CMC are dominating, and a small number of hibernated cells (?10%) indicating irreversible changes. Inclusion of ivabradine (10 mg daily) into the standard (optimal) therapy in patients with UA and PICS, with signs of hibernated myocardium may significantly improve their LVEF (increase by 22.56%) and segmental left ventricular contractility (DLC was decreased by 23.31% and WMSI by 16.77%). Industry - medicine.
