Renal denervation aids in long-term blood pressure control

Patients with uncontrolled hypertension can benefit from renal sympathetic denervation, which leads to notable reductions in systolic blood pressure (SBP) for up to 3 years, reports the proof-of-concept SPYRAL HTN-ON MED trial presented at ACC.22.

“This study parallels the findings of the SPYRAL HTN-OFF MED trial, which treated patients not on antihypertensive medications. Future research will need to identify patients most likely to benefit from this technology,” the researchers said.

SPYRAL HTN-ON MED enrolled 80 patients (mean age 54 years, 13 percent women) with uncontrolled blood pressure who were then randomly assigned to receive renal denervation (n=38) or sham control (n=42). Denervation was performed in a spiral manner across four quadrants using the Symplicity Spyral or Symplicity G3 denervation catheters. Sham patients, in comparison, underwent a renal angiogram and were asked to stay on the table for ≥20 minutes.

Over 3 years of follow-up, renal denervation led to an 18.7-mm Hg decrease in 24-hour SBP, as opposed to only an 8.6-mm Hg drop in sham controls. According to the researchers, the 10.1-mm Hg difference was both statistically (p=0.004) and clinically significant. The same was true for nighttime SBP (19.3 vs 6.6 mm Hg; p=0.002). [ACC 2022, Bavry, A.A. et al]

In comparison, while office SBP (20.9 vs 12.5 mm Hg; p=0.07) was lower in the active intervention group after 36 months, the difference relative to sham was not significant.

Of note, the researchers reported no procedural adverse events, supporting the long-term efficacy and safety of renal denervation for this patient population.

Such benefits of renal denervation became apparent as early as 6 months into the trial, at which point patients in the denervation arm saw a 9.0-mm Hg decrease in 24-hour SBP from baseline, as opposed to only a 1.6-mm Hg reduction in controls (p=0.0051).

Similarly, the 6-month decrease in 24-hour diastolic BP (DBP) was significantly greater in the denervation vs control groups (6.0 vs 1.9 mm Hg; P=0.029). Six-month reductions in office SBP (9.4 vs 2.6 mm Hg; p=0.021) and DBP (5.2 vs 1.7 mm Hg; p=0.048) were likewise significantly greater in the renal denervation than the control group.

“The goal of the trial was to evaluate renal denervation compared with sham control among patients with uncontrolled blood pressure on antihypertensive drug therapy,” the researchers said. All participants enrolled had SBP from 150–180 mm Hg and DBP ≥90 mm Hg; 24-hour ambulatory SBP ranged from 140–170 mm Hg. All antihypertensive medications were being taken for ≥6 weeks.

“Among patients with uncontrolled hypertension on blood pressure medication, this proof-of-concept trial revealed the efficacy of renal sympathetic denervation,” they added, pointing out that aside from proving its safety, no adverse events related to denervation was reported, indicating the overall safety of such a strategy.