Paroxysmal atrial fibrillation and the left heart structure and function in hypertensive patients

Objective . To identify the features of the left heart structure and function in patients with hypertension (HTN) and new onset paroxysmal atrial fibrillation (AF). Design and methods . We included HTN patients with left ventricular hypertrophy and valid 24-hour Holter monitoring carried out over the last month. Patients without AF paroxysms (age from 37 to 82 years, 38,4% men) were divided into two groups: the 1 st group included 32 patients under 55 years of age, the 2 nd group comprised 63 patients 55 years of age and older. Thirty-eight patients with AF paroxysms were included in the 3rd group (age from 56 to 74 years, men 28,9%). The parameters of the left heart structure and function, including the global longitudinal strain of the left ventricle and the left atrium strain in the reservoir and contraction phases, were assessed by echocardiography. Results . The average age of patients in the groups was 44,7 46,4 48,2 vs 61,9 63,7 65,4 vs 63,4 64,8 66,2 years (p < 0,001), and the average duration of HTN was 3,2 4,3 5,6 vs 6,9 7,9 9,1 vs 5,7 6,9 8,1 years (p < 0,001), respectively. The moderate and severe left ventricular hypertrophy and the diastolic dysfunction were found significantly less frequently in the 1st group than in other groups ( 5,0 12,5 28,1 % vs 43,3 55,6 67,8 % vs 36,8 52,6 68,5 %, p < 0,001 and 5,2 18,8 32,3 % vs 51,6 63,5 75,4 % vs 53,6 68,4 83,2 %, p < 0,001). In 1st group, the left atrial reservoir strain was higher than in the 2nd group, and in the 2nd group it was higher than in the 3rd group ( 24,7 26,3 28,0 vs 21,5 22,7 23,9 vs 17,8 19,2 20,5 , p < 0,001). The left atrial contraction strain did not differ in the 1st and 2nd groups and it was higher than in the 3 rd group ( 13,8 14,9 16,0 and 12,9 13,6 14,2 vs 9,6 10,3 11,1 , p < 0,001). The multivariate logistic regression analysis showed that the left atrial strain in the contraction phase is a predictor of AF occurrence in HTN patients over 55 years old depends on. The chances of AF detecting in these patients increase by 3,122 9,211 27,171 times (p < 0,001), if the left atrial strain in the contraction phase is below 13%. Conclusions . The left atrial strain in HTN patients with paroxysmal AF are significantly lower than in patients without cardiac arrhythmias independently of age and the left ventricular state. The left atrial contraction strain ≤ 13% is a predictor of the detection of AF paroxysms during 24-hour Holter monitoring in HTN patients aged 55 years and older.