VISCOSE AND THROMBOCYTIC-AGGREGATION DISORDERS ON PATIENTS WITH MYOCARDIAL INFARCTION WITH STABLE ELEMENTATION OF ST SEGMENT
Authors: Uzun D.U. , Lazoryshynets V.V. , Uzun K.S. K.S. 
Published: January 2022

Relevance. Clinical studies indicate a significant role in the pathogenesis of acute myocardial infarction, the functional state of platelet aggregation and blood viscosity, which determine the nature of blood flow in the vessels at the level of macro– and microcirculation.

Objective: the aim of the study was to analyze changes in viscosity and platelet-aggregation disorders under the influence of different tactical, diagnostic and interventional approaches in patients with myocardial infarction and stable elevation of the ST segment in the presence of multivascular coronary artery disease.

Materials and methods. Patient inclusion criteria for the study: MI with persistent ST-segment elevation; multi-vascular atherosclerotic coronary artery disease; angiographically significant stenosis of the coronary vessels more than 50-70%, at least in 2 projections; functionally significant stenosis of the coronary arteries, according to the fractional blood flow reserve (FBFR) (<0.80). 102 patients were divided into 4 groups of the same type. The groups used 4 different tactical and treatment-diagnostic approaches. Group 1 (n = 25) - occlusion of an infarct-dependent vessel was detected using coronary angiography and its immediate stenting was performed; FBFR was established on days 2-3, and stenosis of infarction-independent arteries was proved; using optical coherence tomography (OCT), the stability, size, length of atheroma was assessed and delayed stenting of these vessels was performed. Group 2 (n = 26) - stenting of the infarct-dependent artery was performed; FBFR was established on days 2-3, but without OCT, followed by stenting of infarct-independent arteries. Group 3 (n = 25) - carried out simultaneous stenting of infarct-dependent and infarct-independent vessels after coronary angiography. Group 4 (n = 26) - only stenting of the infarct-dependent vessel was performed. All patients received standard two-component antiplatelet therapy (acetylsalicylic acid 75-150 mg/day and clopidogrel 75 mg/day) and received 20 mg of atorvastatin and 10 mg of ezetimibe. The results obtained in patients were compared with those results obtained in 30 practically healthy people of the same age and gender. The number of platelets and the concentration of fibrinogen were determined in each subject. Using a viscometer and a laser aggregometer the degree of platelet adhesion, the time of platelet adhesion, the degree of platelet aggregation, and blood viscosity were assessed. All indicators were studied three times - on the first day of myocardial infarction, after 3-4 weeks, and after a year. 

Results. Hyperviscous and hypercoagulable syndromes were established in patients with MI with persistent ST-segment elevation. They manifested themselves in the first weeks by a compensatory increase in the number of platelets, blood viscosity, fibrinogen levels, and an increase in platelet aggregation. Delayed stenting of infarct-independent arteries used in group 1 contributed to a lower amplitude of fluctuations of all laboratory parameters in comparison with other tactical and therapeutic approaches.

Conclusions.  It is possible to optimize the state of viscosity and the processes of adhesion/aggregation of platelets due to the systemic stepwise improvement of arterial blood supply. Traditional tactical and therapeutic-diagnostic principles of management of such category of patients do not fundamentally improve the state of viscous and coagulation-aggregation parameters even when using double antiplatelet therapy.