ANALYSIS OF THE OCCURRENCE OF VARIOUS CARDIOVASCULAR EVENTS IN PATIENTS WITH MYOCARDIAL INFARCTION WITHOUT ST SEGMENT ELEVATION DURING 6TH AND 12TH MONTHS
Authors: Maslovskyi V. I. 
Published: April 2022

Myocardial infarction remains one of the leading causes in the structure of general and cardiovascular morbidity and mortality worldwide. Despite significant progress in the treatment of acute myocardial infarction in most developed countries, the emergence and prevention of early and late complications is of great interest. Existing unified methods of diagnosis and treatment of NSTEMI significantly avoid adverse events in the rehabilitation period of the disease, however, the long-term prognosis of this category of patients remains unfavorable due to the development of myocardial dysfunction after postinfarction remodeling and prognostic adverse arrhythmias. The search for opportunities to predict the development of complications, study of remodeling processes and their impact on the development of electrical instability of the myocardium, which is currently considered a promising area of non-invasive diagnosis of myocardial infarction. With regard to NSTEMI, the unfavorable long-term prognosis is primarily due to the development of myocardial dysfunction, electrical instability of the myocardium or the development of recurrent coronary events.

Aim. To analyze the probability of occurrence of various cardiovascular events in patients with myocardial infarction without ST-segment elevation during 6 and 12 months of follow-up.

Materials and methods. We conducted a comprehensive study of 200 patients with acute myocardial infarction without ST-segment elevation aged 38 to 80 (mean 62.0 ± 0.71, median 62 and interquartile range 55 and 70). A retrospective analysis of patients' condition during 6 and 12 months of follow-up was performed. Surveillance of patients was carried out in the mode of telephone contact with patients, assessment of the condition on scheduled visits (1st, 3rd, 6th and 12th month after hospitalization of patients with acute myocardial infarction) and recording of unscheduled and urgent requests of patients for medical help. We conducted a retrospective analysis of the condition of NSTEMI patients during 6 and 12 months of follow-up. Surveillance of patients was carried out in the mode of telephone contact with patients, assessment of the condition on scheduled visits (1st, 3rd, 6th and 12th month after hospitalization of patients with acute myocardial infarction) and recording of unscheduled and urgent requests of patients for medical help. During the observation of patients we recorded the cardiovascular events, such as cardiovascular death, myocardial infarction, stroke, heart decompensation, heart rhythm disorders.

Results. Analysis of cardiovascular events observed during the year in the examined group of patients revealed that during the first year after an acute coronary event the most common complications were the development of acute decompensation of chronic heart failure, acute heart failure de novo and atrial fibrillation paroxysms de novo. To a lesser extent, events such as episodes of unstable angina, non-fatal myocardial infarction and strokes, and sudden cardiac death have been reported. Time dependence was demonstrated only for the first two, namely an increase in the frequency of complications at a later date – from the 6th to the 12th month compared to the first 6 months of follow-up.

Conclusions. Manifestations of cardiac decompensation and arrhythmia in the delayed period of the disease are associated with manifestations of structural remodeling and electrical instability of the myocardium, while the reduction of fatal complications is a consequence of early invasive treatment strategy.