A failure of endovascular renal denervation (RDN) as a series of point treatments equally distributed within main trunk of renal artery (Symplicity and other methods) was easily predictable. It may only be effective if all renal nerves closely follow the course of renal artery (RA) from aorta to the kidney. However, surgical studies demonstrated that proximally most renal nerves go at a distance from RA and join mainly its distal part. To evaluate whether denervation treatment in distal part of RA is more effective than conventional RDN.Design and Method:
We developed a distal mode of RDN mainly in segmental branches of RA and compared its efficacy and safety to those of conventional RDN in a single-center double-blind randomized controlled parallel group study (ClinicalTrials.gov NCT02667912). Inclusion criteria: both genders, 18–80 years, office systolic BP ≥ 160 or diastolic BP ≥ 100 mmHg despite ≥3 antihypertensive drugs including a diuretic, written informed consent. Exclusion criteria: secondary hypertension, 24h-mean systolic BP < 135 mmHg, eGFR < 30 mL/min/m2, extended RA disease, comorbidities causing high risk of the intervention (investigator's assessment). Randomization was done in Cath lab using computer-generated random sequence and remained unknown to patients and outcome assessors. Primary outcome was the between-group difference in baseline-to-6-month change of 24h-mean systolic BP.Results:
Of 45 patients enrolled in the study 24 undergone distal RDN and 21 – conventional RDN. Of them 41 (89%) completed 6 months follow-up and were included in per-protocol analysis. The 24 h mean systolic BP decreased powerfully in the distal treatment group (n = 23): −22.4 (SD 20.5) mmHg, p < 0.0001 and only slightly - in conventional RDN group (n = 18): −8.7 (SD 18.8), p = 0.06. The difference between the groups was statistically significant, p = 0.036.Conclusions:
Distal RDN is superior to conventional mode of the intervention, however, currently may only be done with ablation catheters. Complex devices (baskets, balloons) need redesigning for use in segmental branches of RA.