STATE OF CARDIOVASCULAR SYSTEM IN EMERGENCY WORKERS OF THE CHORNOBYL ACCIDENT AFTER SURVIVE FROM COVID-19.

OBJECTIVE based on a comparative analysis of cardiovascular system clinical, structural, and functional state bothin emergency workers (EW) of the accident at the Chernobyl Nuclear Power Plant (ChNPP) and nоnirradiated individuals, to identify changes of cardiovascular system status that can be associated with COVID19 or the consequences of radiation, but not with the natural progression of cardiovascular diseases (CVD).

MATERIALS AND METHODS The study included 46 EW and 21 unexposed patients (comparison group - CG) who survived COVID19 in 2020-2022 (groups EWC+ and CGC+ respectively), and EW and 21 unexposed individuals without a history of COVID19 (groups EWC and CGC respectively). All EW and CG individuals were male under longterm supervision, and underwent regular examination and treatment for cardiovascular diseases (CVD) in the cardiology department of the NRCRMHO in the pre and postCOVID period. During the examination of patients, generalclinical, laboratory, statistical methods, echocardiography, and daily electrocardiogram monitoring were used.

RESULTS During the comparable period of time between the pre and postCOVID examinations in the EW and nonirradiated individuals, regardless of whether they had COVID19 or not, a deterioration of cardiovascular system status was revealed, which consisted in the appearance of new cases of hypertensive heart disease, coronary heart disease, heart failure, rhythm and conduction disorders. Echocardiographic indicators, which characterize the structural and functional state of the left ventricle, did not have statistically significant difference both in each groupbetween the two examinations in pre and postCOVID period and between different groups.

CONCLUSIONS The lack of the significant difference in clinical course of CVD and the structural and functional stateof myocardium between patients, who were sick with COVID19 or not, is more indicative of the natural progressionof cardiovascular system pathology. Hypothetically, it can be assumed that in elderly people (60-75 years old) having CVD, past radiation exposure does not significantly affect cardiovascular system status in the present.