Effects of renal sympathetic denervation on heart rate and atrioventricular conduction in patients with resistant hypertension

Abstract

Background: Renal sympathetic denervation (RDN) reduces sympathetic activity and blood pressure (BP) in patients with resistant hypertension. The present study aimed to investigate the effects of RDN on HR and other electrocardiographic parameters.

Methods: 136 patients aged 62.2 ± 0.8 years (58% male, BP 177 ± 2/93 ± 1 mmHg) with resistant hypertension underwent RDN. BP and a 12-lead electrocardiogram (ECG) were recorded before, 3 months (n=127), and 6 months (n=88) after RDN.

Results: After 3 months (3M) and 6 months (6M), systolic BP was reduced by 25.5 ± 2.4 mmHg (p<0.0001) and 28.1 ± 3 mmHg (p<0.0001). HR at baseline was 66.1 ± 1 beats per minute (bpm) and was reduced by 2.6 ± 0.8 bpm after 3 months (p=0.001) and 2.1 ± 1.1 bpm after 6 months (p=0.046). Patients with HR at baseline between 60-71 bpm and ≥ 71 bpm had a reduction of 2.9 ± 7.6 bpm (p=0.008) and 9.0 ± 8.6 bpm (p<0.0001), respectively, whereas in patients with baseline HR<60 bpm HR slightly increased after 3 months (2.7 ± 8.4 bpm; p=0.035). Neither baseline HR nor change of HR correlated with the reduction of systolic BP. The PR interval was prolonged by 11.3 ± 2.5 ms (p<0.0001) and 10.3 ± 2.5 ms (p<0.0001) at 3 and 6 months after RDN, respectively.

Conclusions: Renal sympathetic denervation reduced heart rate and the PR interval as indicators of cardiac autonomic activity.

Keywords: Cardiac autonomic activity; Renal nerve ablation; Resistant hypertension; SIMPLYCITY-HTN.