Shchukina O. Improving the effectiveness of predicting clinical outcomes in patients with acute coronary syndrome without ST segment elevation at the hospital and post-hospital stages

The dissertation is devoted to improving the effectiveness of predicting the clinical course of acute coronary syndrome without ST segment elevation, by studying clinical and additional research methods, in particular, ischemic modified albumin (IA), cell-free DNA (cfDNA), advanced glycation end products (AGES) and pulse wave velocity (PWV). 121 patients who met the following criteria were recruited: 1) presence of ACS without ST segment elevation with a typical anginal episode, destabilization of the condition for less than 72 hours, 2) absence of chronic diseases in the stage of exacerbation and decompensation, 3) absence of chronic congestive heart failure deficiencies, 4) the patient's consent to participate in the study. Patients with moderate and severe anemia and/or a history of chronic renal failure (4-5 stages) were excluded. At the hospital stage, in addition to collecting complaints and anamnestic data, objective examination of patients, standard laboratory and instrumental studies, additional biomarkers were determined: IA, cfDNA, AGES on the 1st and 6th day of hospital stay. Also PWV was measured during hospitalisation. 51 patients (42%) underwent Holter ECG monitoring on the 1st and 6th days. Upon discharge from the hospital, the patients were given recommendations regarding lifestyle modification and drug treatment. In the future, with the help of face-to-face visits, telephone visits and monitoring of patients' electronic cards, information on clinical outcomes was collected. The average period of observation of patients was 41.5 [29.4; 49.7] monthes. Scientific novelty of the obtained results. It was a prospective study was conducted, which included the study of several additional markers: AGES, cfDNA, IA and PWV. One of the novel aspects of this scientific work is the simultaneous study of the above-mentioned biomarkers in patients with acute coronary syndrome without ST-segment elevation with the subsequent collection of information about clinical outcomes in the post-hospital stage, because most studies are conducted on the study of only one marker. The prognostic possibilities in patients with acute coronary syndrome without ST-segment elevation both at the hospital stage (levels of ischemia, cytolysis) and after discharge from the hospital have been improved. Using the PWV indicator above 10 m/s, it is possible to delineate a group of patients with more pronounced cytolysis and prolonged ischemia at the hospital stage. AGES level > 0,154 mg/ml provides information about a high risk of both long-term general ischemia and the presence of ST segment depression on Holter monitoring on the 6th day. The possibility of predicting the development of a myocardial infarction using the level of IA during hospitalization and the dynamics of cfDNA, heart rhythm disorders - the dynamics of AGES, and the combined clinical event - the dynamics of cfDNA is shown. Theoretical and practical value of work. Markers such as cfDNA and IA can be used not only to predict post-hospital events, but also as intermediate markers during hospitalization to assess the activity of cytolysis and ischemia, respectively. This will help to optimize anti-ischemic and anti-thrombotic therapy in patients with acute coronary syndrome without ST-segment elevation. Determination of ambulatory PWV and/or AGES level on day 1 after hospital admission will provide information on the risk of ischemia and cytolysis during hospitalization. Determination of the level of IA on the 1st day, the dynamics of cfDNA and AGES during the inpatient period will help to predict adverse clinical events in the post-hospital period.