Durability of the Blood Pressure Effects of Renal Pelvic Denervation in Patients with Hypertension during a 12-Month Observation

Abstract

<b><i>Introduction:</i></b> We previously completed a trial of renal pelvic denervation for treating hypertension that reduced blood pressure by the 2-month primary endpoint. However, information on the durability of effectiveness is a critical requirement for device therapy and we now report data up to 12 months. <b><i>Methods:</i></b> This was an open-label, single-arm feasibility study in patients with increased blood pressure despite taking an average of 2.7 medications. The key endpoint reported here was ambulatory blood pressure at 12 months following renal pelvic denervation. <b><i>Results:</i></b> In the 17 patients (mean age: 56) studied, there was a reduction from the baseline of 148 + 8.7 mm Hg in the primary endpoint of mean daytime systolic blood pressure at 12 months of 19.1 (26.7, 11.6) mm Hg, <i>p</i> < 0.001, as compared with the 2-month result of 19.4 (24.9, 14.0) mm Hg. The 24-h systolic blood pressure fell by 19.3 (26.7, 11.9), <i>p</i> < 0.001, and nighttime systolic fell by 18.7 (27.5, 9.8), <i>p</i> < 0.001, mm Hg at 12 months. Diastolic pressures also fell significantly from baseline at 12 months. As well, automated office systolic blood pressure was reduced from the baseline of 156.5 ± 12.3 by 24.8 (33.2, 16.8) mm Hg, <i>p</i> < 0.001, at 12 months as compared with 22.4 (31.5, 13.3) at 2 months. All blood pressure changes at 12 months were not different from those at 2 months, thus confirming the durability of the procedure. There were no serious procedural, clinical, or laboratory adverse events related to the intervention. Serum creatinine fell from 1.03 ± 0.22 to 0.82 ± 0.16 mg/dL, and estimated glomerular filtration rate rose from 79.6 ± 17.8 to 96.3 ± 16.4 mL/min/1.73 m<sup>2</sup> by 12 months, again sustaining effects seen at 2 months. <b><i>Conclusion:</i></b> These findings provide evidence that the significant blood pressure-lowering effects of renal pelvic denervation are durable and safe for at least 1 year and provide the basis for a pivotal randomized blinded trial to further define the safety and effectiveness of this procedure.

One More Step in the Renal Denervation Trek

“…The impressive blood pressure reduction results from Weber et al [1] will need to show replication in a larger, double-blind sham-controlled cohort, hopefully with an assessment of the adequacy of blinding and a strategy to minimize alteration of medication therapy during the blinded period leading up to the primary outcome assessment. We await confirmatory studies of the transurethral approach to renal denervation with tempered enthusiasm, mixed with a dash of cautious optimism.…”

“…In this issue of the Journal, Weber and colleagues [1] report the longer-term durability, that is, at 12-month follow-up, of blood pressure reduction following renal denervation undertaken by a transurethral route. This represents a follow-up period of ten additional months on top of their 2-month results, reported previously [2].…”

“…This has been noted repeatedly in the clinical trials undertaken by transarterial denervation, as well as in the real-world experience of the Global Simplicity Registry. In the study of Weber and colleagues [1], the large daytime ambulatory systolic blood pressure reduction achieved at 2 months was sustained, but not increased, at the 12-month time period. This is a small study with 17 patients, but it does raise some interesting physiologic thoughts regarding the renal nerves.…”