The Efficacy of Renal Denervation in Treating Resistant Hypertension: A Systematic Review

Resistant hypertension is blood pressure (BP) that is persistently above target in spite of the maximally tolerated usage of at least three anti-hypertensives simultaneously. The sympathetic nervous system is instrumental in blood pressure (BP) regulation. Renal (sympathetic) denervation involves using ablative energy to disrupt the sympathetic nerves in renal arteries. This systematic review examines the efficacy of this treatment modality. Abiding by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, we conducted an extensive literature search in five databases, Cochrane Library, Google Scholar, PubMed, PubMed Central (PMC), and ScienceDirect, to retrieve studies that are free, open access, and published in English done within the past four years. Nineteen articles passed critical appraisal. These articles were randomized controlled trials (RCT), a case report, a cross-sectional study, a cohort study, and previous reviews. Renal denervation (RDN) was generally superior to sham control in patients with resistant hypertension for reducing various systolic blood pressure (SBP) measures, including 24-hour ambulatory, daytime, and nighttime SBP. The efficacy was highest in patients whose baseline SBP was higher. BP reduction was sustained for years post-procedure. The procedure had a good safety profile with no severe complications. Future studies should compare the efficacy of different types of renal denervation, such as ethanol ablation versus radiofrequency ablation, and renal denervation against other procedure-based treatment modalities, such as carotid baroreceptor stimulation and transcranial direct current stimulation.