Changes in Plasma Renin Activity After Renal Artery Sympathetic Denervation

BACKGROUND The renin-angiotensin-aldosterone system plays a key role in blood pressure (BP) regulation and is the target of several antihypertensive medications. Renal denervation (RDN) is thought to interrupt the sympathetic mediated neurohormonal pathway as part of its mechanism of action to reduce BP. OBJECTIVES The purpose of this study was to evaluate plasma renin activity (PRA) and aldosterone before and after RDN and to assess whether these baseline neuroendocrine markers predict response to RDN. METHODS Analyses were conducted in patients with confirmed absence of antihypertensive medication. Aldosterone and PRA levels were compared at baseline and 3 months post-procedure for RDN and sham control groups. Patients in the SPYRAL HTN-OFF MED Pivotal trial were separated into 2 groups, those with baseline PRA >= 0.65 ng/ml/h (n = 110) versus < 0.65 ng/ml/h (n = 116). Follow-up treatment differences between RDN and sham control groups were adjusted for baseline values using multivariable linear regression models. RESULTS Baseline PRA was similar between RDN and control groups (1.0 +/- 1.1 ng/ml/h vs. 1.1 +/- 1.1 ng/ml/h; p = 0.37). Change in PRA at 3 months from baseline was significantly greater for RDN compared with control subjects (-0.2 +/- 1.0 ng/ ml/h; p = 0.019 vs. 0.1 +/- 0.9 ng/ml/h; p = 0.14), p = 0.001 for RDN versus control subjects, and similar differences were seen for aldosterone: RDN compared with control subjects (-1.2 +/- 6.4 ng/dl; p = 0.04 vs. 0.4 +/- 5.4 ng/dl; p = 0.40), p = 0.011. Treatment differences at 3 months in 24-h and office systolic blood pressure (SBP) for RDN versus control patients were significantly greater for patients with baseline PRA >= 0.65 ng/ml/h versus < 0.65 ng/ml/h, despite similar baseline BP. Differences in office SBP changes according to baseline PRA were also observed earlier at 2 weeks post-RDN. CONCLUSIONS Plasma renin activity and aldosterone levels for RDN patients were significantly reduced at 3 months when compared with baseline as well as when compared with sham control. Higher baseline PRA levels were associated with a significantly greater reduction in office and 24-h SBP. (SPYRAL PIVOTAL SPYRAL HTN-OFF MED Study; NCT02439749) (J Am Coll Cardiol 2021;77:2909-19) (c) 2021 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The study aimed to evaluate the impact of renal denervation (RDN) on the renin-angiotensin-aldosterone system in blood pressure regulation. Results showed that plasma renin activity and aldosterone levels significantly decreased compared to baseline in RDN patients at 3 months, with higher baseline PRA levels associated with a more significant reduction in blood pressure.