Immediate post-ablation renal nerve stimulation predicted blood pressure reductions 6 months following renal denervation

Abstract

Abstract Background Renal denervation (RDN) has been recognized as an alternative treatment strategy for blood pressure (BP) control. There is no consensus on which intra-procedural parameters could reliably predict BP-lowering responses following RDN, which usually occur months later. Purpose This study aimed to evaluate systolic BP (SBP) changes induced by renal nerve stimulation (RNS) during RDN and its associations with BP-lowering responses 6 months following RDN. Methods Seventeen patients with hypertension who underwent radiofrequency RDN between February 2019 and March 2021 were prospectively included. RNS was performed immediately before and after RDN in bilateral proximal and distal main renal arteries under general anesthesia. The responder was defined as 24-hour SBP reduction of ≥10 mmHg 6 months following RDN. Results RNS-induced SBP changes significantly decreased after RDN in all 4 sites of bilateral main renal arteries (all p<0.05). The mean 24-hour SBP were 144±16 mmHg and 131±15 mmHg at baseline and 6 months after RDN, respectively. Nine (53%) patients were responders. Compared to non-responders, the responders had significantly lower RNS-induced SBP changes in proximal main renal arteries immediately after RDN (right, 15.3±9.6 mmHg vs. 31.6±9.6 mmHg, p=0.005; left, 11.6±6.9 mmHg vs. 27.9±10.2 mmHg, p=0.002). All 7 patients with RNS-induced SBP increases of <20 mmHg after RDN in bilateral proximal main renal arteries were responders. Conclusions An RNS-induced SBP increase of <20 mmHg in bilateral proximal main renal arteries immediately after RDN was associated with significant 24-hour SBP reductions 6 months following RDN. Whether RNS-induced SBP changes could predict or even guide RDN strategies awaits further verifications.