Difference in the Effect of Renal Denervation on Heart Rate Variability in Resistant Hypertension With and Without Disturbance of Glucose Metabolism After 12 Month Follow-Up

Abstract

Objective: To investigate the effects of renal denervation (RDN) on heart rate variability (HRV) in resistant hypertension (RHTN) with and without disturbance of glucose metabolism. Design and method: In a single-arm prospective interventional study with renal denervation (NCT02667912 and NCT01499810 on ClinicalTrial.gov) were included 87 patients with RHTN: 39 patients without disturbance of glucose metabolism (RHTN group) (mean age 51.2 ± 8.5years, 20 (51%) men, 24-hour (24 h) blood pressure (BP) (systolic/diastolic) 162.3 ± 19.4/99.6 ± 13.5 mmHg); 34 patients with type 2 diabetes mellitus (RHTN + DM group) (mean age 59.2 ± 7.8 years, 11 (32%) men, 24 h BP 157.8 ± 17.4/80.1 ± 12.4 mmHg, mean HbA1c 6.9 ± 1.4%) and 14 patients with impaired glucose tolerance (RHTN + IGT group) (mean age 54.0 ± 10.0 years, 3 (27%) men, 24 h BP 156.6 ± 14.3/89.5 ± 15.6 mmHg). All patients were underwent ABPM and 24-h Holter monitoring with analysis of time and frequency domain-based HRV. Follow-up after 12 months was completed by 38 patients of RHTN group, 22 patients of RHTN + DM group and 9 patients of RHTN + IGT group. Results: There was a significant decrease in 24 h BP in all groups at 12 months after RDN (p < 0,001). In the RHTN group, there were no significant changes in both high frequency (HF) and low frequency (LF) (for HF from 14.8 (8.6; 24) to 29.5 (19.0; 40), p > 0.05, and for LF (from 23.1 (15, 0; 61) to 61.0 (40.5; 70), p > 0.05). There were also no significant changes in both LF and HF in the RHTN + IGT group (for LF from 52 (38; 61) to 50 (42; 61), p > 0.05, for HF from 37 (30; 50) to 44 (29; 47), p > 0.05). On the contrary, in the RHTN + DM group, there was a significant decrease in LF (from 55 (39; 63) to 50 (42; 61), p = 0.004), which occurred independently from BP effects, and a non-significant increase in HF. Other measured HRV parameters (mean NN, SDNN, SDNN-I, SDANN-I, r-MSSD, pNN50) were unchanged in all groups (p > 0.05). Conclusions: RDN was associated with a reduction of LF, HRV parameters that mainly reflect sympathetic overactivity, only in patients with resistant hypertension and diabetes mellitus.