Epicardial fat and left atrial mechanical dispersion in patients with hypertension with persistent atrial fibrillation and without cardiac arrhythmia

Abstract

Aim. To study the relationship between the amount of epicardial left atrial fat and left atrial mechanical dispersion (LAMD) in hypertensive patients with persistent atrial fibrillation (AF) and without cardiac arrhythmias.Material and methods. The main group included 100 hypertensive patients with persistent AF, who underwent transesophageal echo cardiography (TEE) before the elective cardioversion, and transthoracic echocardiography (TTE) after cardioversion and disappearance of atrial stunning. The control group included 24 hypertensive patients without cardiac arrhythmias, who underwent TEE for other indication. The thickness of atrial septum and left lateral ridge was measured by TEE. The average thickness of these structures was designated as left atrial fat. The time to peak of longitudinal myocardial strain in 6 left atrium segments was determined by speckle-tracking echocardiography. LAMD was calculated as a percentage of the standard deviation of the obtained values to cardiac cycle duration.Results. The median left atrial fat thickness in the main and control groups was 8,03 [6,78; 8,95] and 5,23 [4,48; 5,80] mm (p<0,0001), median LAMD — 2,68 [2,41; 2,83] and 0,95 [0,62; 1,11]% (p<0,0001). There was a positive correlation between left atrial fat thickness and LAMD in the main group (r=0,556; p<0,0001). This relationship did not reach the level of statistical significance in the control group, (r=0,358; p=0,0860). There was no independent relationship between body mass index and left atrial fat thickness in the patients (r=0,027; p=0,7651).Conclusion. In hypertensive patients with persistent AF, compared with patients without rhythm disturbances, the average values of left atrial fat thickness and LAMD are significantly higher. The increase in left atrial fat thickness is associated with the increase in LAMD in hypertensive patients with AF. There was no correlation between left atrial fat thickness and LAMD in hypertensive patients without rhythm disturbances. There was no effect of body mass index on left atrial fat thickness in the present study.