The REDUCE HTN: REINFORCE: Randomized,Sham-Controlled Trial of Bipolar Radiofrequency Renal Denervation for the Treatment of Hypertension

ObjectivesThe aim of this study was to investigate bipolar radiofrequency renal denervation in patients with hypertension not receiving medications at baseline.BackgroundA blood pressure–reducing effect of renal denervation has been difficult to isolate in clinical investigations.MethodsREDUCE HTN: REINFORCE (Renal Denervation Using the Vessix Renal Denervation System for the Treatment of Hypertension) was a randomized, sham-controlled multicenter trial. Patients with office systolic blood pressure (SBP) of 150 to 180 mm Hg and average 24-h ambulatory SBP of 135 to 170 mm Hg after medication washout underwent bipolar radiofrequency renal denervation or a sham procedure. The planned outcome was 8-week change in 24-h ambulatory SBP. Enrollment was terminated for apparent futility before a sufficient sample for powered efficacy comparisons was enrolled. Safety assessments included all-cause death, renal failure, severe hypotension or syncope, hypertensive crisis, and renal artery stenosis.ResultsBaseline 24-h blood pressure was 148.3 ± 10.9/85.7 ± 9.1 mm Hg for the denervation group (n = 34, mean age 58.5 ± 10.1 years, 47% women) and 149.1 ± 7.2/86.4 ± 9.8 mm Hg for the control group (n = 17, mean age 58.2 ± 9.8 years, 24% women). At 8 weeks, mean 24-h SBP reductions for the renal denervation and control groups were −5.3 mm Hg (95% confidence interval [CI]: −8.8 to −1.8 mm Hg) and −8.5 mm Hg (95% CI: −13.3 to −3.8 mm Hg), respectively (difference 3.3 mm Hg; 95% CI: −2.8 to 9.3 mm Hg; p = 0.30). Antihypertensive medications could then be added. By 6 months, decreases in SBP were greater for the denervation group, yielding between-group differences of −7.2 mm Hg (95% CI: −15.2 to 0.8 mm Hg; p = 0.08), −9.7 mm Hg (95% CI: −17.7 to −1.7 mm Hg; p = 0.02), and −11.4 mm Hg (95% CI: −19.2 to −3.7 mm Hg; p < 0.01) for 24-h, daytime ambulatory, and office measurements, respectively. Through 12 months, 1 patient (renal denervation group) had a hypertensive urgency requiring immediate management, and 1 experienced progression of renal artery stenosis.ConclusionsFuture studies of radiofrequency renal denervation must anticipate delayed treatment effects. (Renal Denervation Using the Vessix Renal Denervation System for the Treatment of Hypertension [REDUCE HTN: REINFORCE]; NCT02392351)