Effect of catheter-based renal denervation on orthostatic blood pressure adaptations in patients with uncontrolled hypertension

Abstract Background Orthostatic blood pressure (BP) adaptations are associated with the risk of adverse cardiovascular events. This study aimed to evaluate the effect of catheter-based renal denervation (RDN) on orthostatic BP adaptations in patients with uncontrolled hypertension. Methods The Iberis-HTN Trial is a randomized, sham-controlled, multicenter study conducted at 16 centers in China. Eligible patients were randomly assigned to undergo either radiofrequency RDN or a sham procedure. As one of the participating centers in the Iberis-HTN trial, BP and heart rate (HR) changes during a 3-min orthostatic challenge from supine to standing were measured at baseline and 6 months after randomization. Results Between March 2018 and January 2022, a total of 30 patients were assigned to the RDN group (n = 15) and sham group (n = 15). Of these 30 patients, 10 in the RDN group and 12 in the sham group completed orthostatic BP measurements at both baseline and 6 months. At 6 months, the RDN group exhibited a significantly greater reduction in ambulatory blood pressure, office systolic blood pressure (SBP) and BP in both supine and standing positions compared to the sham group. The changes in orthostatic SBP and diastolic blood pressure (DBP) at 3 minutes, and the maximum changes during a 3-min orthostatic test at 6 months were smaller in the RDN group than in the sham group after adjusting for baseline values (3 min: SBP -9.4 mmHg 95%CI: -16.0 to -2.8, P = 0.008; DBP -6.7 mmHg 95%CI: -12.4 to -1.1, P = 0.022. Maximum: SBP -10.9 mmHg 95%CI: -21.1 to -0.6, P = 0.039; DBP -9.2 mmHg 95%CI: -16.2 to -2.1, P = 0.013). The orthostatic HR changes at 6 months were similar between the RDN and sham group. Conclusions Catheter-based radiofrequency RDN significantly reduced office BP, ambulatory BP, and BP in both supine and standing positions during active standing at 6 months compared to the sham group. Additionally, RDN mitigated the inappropriate increase in orthostatic BP and partly restored the normal response pattern to orthostatic challenges. Further studies are warranted to investigate whether the differential effects of RDN on orthostatic BP correlated with long-term cardiovascular outcomes.