Renal denervation results in blood pressure lowering at mild hypertension
ESC 2017 - Barcelona
Renal denervation lowers blood pressure in hypertensive patients not taking medication (SPYRAL HTN-OFF MED)
Presented at the ESC congress 2017 by: Michael Boehm (Homburg/Saar, Germany)
Renal denervation is a minimally invasive catheter-based procedure that denervates the renal nerves, which help regulate blood pressure. Because the sympathetic nervous system is active in hypertension, this method was initially developed for patients with resistant hypertension. The SYMPLICITY HTN-3 trial failed to show significant blood pressure lowering with this technique.. Subanalyses of SYMPLCITY HTN-3 suggested that variation occurred in therapy adherence, that denervation of the renal arteries was incomplete and that patients had been included with isolated systolic hypertension (ISH).
Based on these observations, the SPYRAL HTN-OFF MED trial studied renal denervation in 80 patients with mild hypertension (no ISH), naïve for therapy of who had stopped blood pressure lowering therapy for a minimum of 4 weeks. Contrary to the mono-electrode, sequential ablation system, often inexperienced surgeons and treatment of only the main artery, the simultaneous four-electrode ablation system was used by very experienced physicians, and also smaller arteries were treated. The latter resulted in multiple ablations per patient.
- Difference in blood pressure from baseline till 3 months between renal denervation and sham treatment: 24-hrs SBP -5.0 mmHg (95% CI -9.9 to -0.2, P=0.04), 24-hrs DBP -4.4 (95% CI -7.2 to -1.6, P=0.002, office SBP -7.7, 95% CI -14.0 to -1.5, P=0.02, office DBP -4.9 (95% CI -8.5 to -1.4, P=0.008). 24-hrs SBP reduction was -5.5 mmHg in treated patients and -0.5 mmHg in control patients and the 24-hrs DBP were -4.8 and -0.4 mmHg respectively.
- No serious bleedings were seen with this more aggressive renal denervation method. The same was true for other safety endpoints.
The SPYRAL HTN-OFF MED trial showed efficacy of renal denervation in mildly hypertensive subjects. Clinically relevant reductions of blood pressure were seen in patients with mildly elevated blood pressure who were not receivind BP-lowering medication. In the press release Boehm said “the efficacy of renal denervation in this study might bet he result of the new procedure, in which the aim was complete denervation, along with the fact that patients did not take blood pressure lowering medication, which may have affected the results of previous studies.”
The procedure did not result in extre safety events, despite the higher number of ablations. A larger study will now be set up.
- Our reporting is based on the information provided at the ESC congress -