Features of circadian regulation and cardiac rhythm disorders in patients with arterial hypertension and frequent recurrences of atrial fibrillation

Abstract

The aim — to determine the features of circadian regulation and cardiac rhythm disorders according to Holter monitoring of electrocardiogram (HM ECG) in patients with arterial hypertension (AH) and frequent recurrences of atrial fibrillation (AF), depended on the clinical form and vegetative variant of arrhythmia.Materials and methods. There were examined 146 patients aged from 37 to 86 years with AH stage II complicated by frequent recurrences of AF. As a comparison group, 26 patients were examined aged 39 to 74 years with AH II stage without AF, that was ruled out with anamnesis data and HM ECG. The duration of the arrhythmic anamnesis ranged from 1 to 30 and mean duration was 5.7 ± 0.5 years. Paroxysmal form of AF was in 56 (38.4 %) patients and persistent form of AF was in 90 (61.6 %) patients. The anamnesis of AH ranged from 1 to 40 and mean duration was 11.6 ± 0.6 years. All patients underwent HM ECG according to the standard protocol.Results and discussion. In groups with AH and AF in contrast to group without AH, the total number of supraventricular premature contractions (SPC) per day was higher (p < 0.0001). In the groups with AH and AF there was the prevalence of the pair and group of SPC (p < 0.0001). Short asymptomatic episodes of supraventricular paroxysmal tachycardia (SVPT) were defined in 35.7 % of patients with paroxysmal and in 33.3 % of patients with persistent AF. SVPT wasn’t defined in group with AH (p < 0.001). The analysis of painless myocardium ischemia cases demonstrated statistically significant differences in such cases registration in patients with persistent AF comparing with patients without AF (38.9 and 19.2 % respectively; p = 0.05). The dispersion of the interval QT was significantly higher in the groups of patients with AF in comparison with group without AH (p < 0.05). The ratio of the dispersion PQ/QT was lower in groups of AH and AF compared with the group of AH (p < 0.05).The daily heart rate (p < 0.04) and the circadian index (CI) (p = 0.02) are significantly lower and the mean daily number of asymptomatic SVTS episodes is significantly higher (p < 0.04) in patients with vagal variant of AF. In patients with mixed variant of AF the value of CI (p < 0.05), the daily amount of SPC (p < 0.04) and the number of episodes of paired and group SPC (p < 0.04) are significantly higher.Conclusions. In groups of AH and AF in comparison with group owithout AH, the number of SPC, paired and group SPC, SVPT were higher, increasing of the dispersion of QT and dispersion ratio PQ/QT was observed. The study did not reveal any fundamental differences between clinical forms of AF. The heart rate and CI are significantly lower and the number of asymptomatic episodes of the SVTS is significantly higher in patient with vagal variant of AF. The CI value, daily amount of SPC and episodes of paired and group SPC were significantly higher in patients with mixed variant of AF.