ABSTRACT NUMBER: ESOC2026A1920 INTRACARDIAC AND SYSTEMIC HEMODYNAMIC PARAMETERS IN PATIENTS WITH ATRIAL FIBRILLATION AND FLUTTER DEPENDING ON LYMPHOCYTES AND MONOCYTES SUBPOPULATION CHARACTERISTICS AND COMPOSITION IN PERIPHERAL BLOOD

Abstract Background and aims The Aim – to compare intracardiac and systemic hemodynamic parameters in patients with paroxysmal and persistent forms of atrial fibrillation and atrial flutter associated with arterial hypertension, depending on peripheral blood lymphocyte and monocyte subpopulations characteristics. Methods 147 patients were included into the study:103 with arrhythmias were divided into three groups: I – paroxysmal AF; II – persistent AF; III – persistent AFl. The levels of lymphocyte and monocyte subpopulations were assessed using flow cytometry. Hemodynamic parameters were evaluated via transthoracic echocardiography, office blood pressure measurements, 24-hour ambulatory blood pressure monitoring, transesophageal echocardiography. Results The absolute and relative numbers of cytotoxic cells (NK and NKT cells) in groups I–III were significantly higher, the number of classical and intermediate monocyte fractions was increased but regulatory T-cell count was reducted compared to healthy individuals. Comparison of echocardiographic parameters revealed statistically significant differences (p ≤ 0.05) in left ventricular linear dimensions (end-diastolic diameter, end-systolic diameter, interventricular septal thickness, posterior wall thickness), transverse dimensions of the left atrium and right ventricle, E/A and left ventricular mass indices. Compared with group V, significant differences were only in end-systolic diameter, left atrial size, interventricular septal thickness, and posterior wall thickness. According to 24-hour blood pressure monitoring mean and maximal diastolic pressure significantly differed. Conclusions Patients with arrhythmias presented elevated levels of pro-inflammatory monocyte subpopulations, increased numbers of cytotoxic T cells, and reduced levels of regulatory T cells. Echocardiographic data indicate more pronounced structural myocardial changes and diastolic dysfunction. Measured systolic and diastolic blood pressure values differed significantly. Conflict of interest Olena Marchenko. Nothing to disclose