Arterial hypertension in combination with atrial fibrillation and extracardiac diseases

Aim. To evaluate the character of the course and to determine the features of biochemical manifestations in patients with atrial fibrillation and arterial hypertension combined with extracardiac diseases.

Methods. To study the features of the course of persisting form of atrial fibrillation (AF) in patients with arterial hypertension (AH) stage 3 combined with extracardiac diseases. 374 patients aged 45 to 65 years were examined. Among them chronic obstructive pulmonary disease (COPD; n = 37), diffuse toxic goiter (DTG; n = 33), hypothyroidism (HT; n = 69), diabetes mellitus (DM; n = 49) and abdominal obesity (AO; n = 64) of mild and moderate degree were detected. 5 groups were formed: group 1 - AH + AF + COPD, group 2 - AH + AF + HT, group 3 - AH + AF + DTG, group 4 - AH + AF + DM, group 5 - AH + AF + AO. The control group included 56 patients with AH and AF without concomitant diseases, and the comparison group included 36 patients with AF without AH and 30 patients with AH without AF. The study evaluated clinical, anthropometric and laboratory parameters, the results of instrumental diagnostic investigation. The level of galectin-3 was determined in the serum by ELISA. The concentration of brain natriuretic peptide (NT-proBNP) was measured with a panel “NT-proBNP - ELISA - Best”. Multiple comparisons of the groups were performed with Kruskal - Wallis test. To compare binary and categorical parameters, exact two-tail Fisher’s test was used. Optimal multivariate regression models were developed directly and reversely. Verification of statistical hypotheses was carried out with critical value of significance p = 0.05 i.e. the difference was considered statistically significant if p < 0.05. All statistical calculations were performed with the use of R-Studio soft.

Results. When assessing the lipid profile in the studied groups, significant differences were detected for HDL (high density lipoprotein) the values of which were the highest in the control group; TC (total cholesterol) was significantly lower in group 1 and 2; LDL (low density lipoprotein) and TG (triglycerides) - in group 3. The level of uric acid in the serum in all clinical groups was higher compared to those of the control group but significance was reached only in group 3. The concentration of K+ in the blood was significantly higher in all groups compared to the control group. The study of NT-proBNP and galectin-3 as markers reflecting the processes of remodeling and myocardial fibrosis in patients with atrial fibrillation combined with arterial hypertension, demonstrated that the average level of NT-proBNP in all groups was higher than in the control group but the difference was significant only in group 5. The level of galectin-3 in the serum of patients with arterial hypertension and atrial fibrillation combined with comorbid extracardiac pathology was significantly higher in the groups compared to the control group (except for group 3 where the number of patients was the lowest) and significantly lower in the comparison group of patients with atrial fibrillation without arterial hypertension.

Conclusion. The course of arterial hypertension and atrial fibrillation with concomitant extracardiac diseases is characterized by the changes of biochemistry, which manifest as the changes of lipid profile, electrolyte content and factors inducing fibrosis. The obtained data confirm the possible role of galectin-3 as a biological marker of fibrosis and myocardial remodeling in patients with AF and AH and comorbid extracardiac pathology.