Title:Renal Innervation in Resistant Hypertension: A Review of Pathophysiology and Renal Denervation as Potential Treatment
Volume: 16
Issue: 2
Author(s): Anthony L. Wilson, Jason Gandhi, Yiji Suh, Gunjan Joshi, Noel L. Smith and Sardar Ali Khan*
Affiliation:
- Department of Physiology and Biophysics, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794,United States
Keywords:
Resistant hypertension, renal denervation, renal artery, renal sympathetic nerve activity, nerve ablation, stroke.
Abstract:
Background: Advances in treatment and increased awareness have improved the prognosis
for many patients with hypertension (HTN). Resistant hypertension (RH) refers to a subset of
hypertensive individuals who fail to achieve a desired blood pressure (BP) despite concurrent use of
3 different classes antihypertensive agents, one being a diuretic, and proper lifestyle changes. The
prevalence and prognosis of RH are unclear owing to its heterogeneous etiologies, risk factors, and
secondary comorbidities. Previous research has provided evidence that increased renal sympathetic
nerve activity (RSNA) within the renal artery contributes to RH development. Renal denervation
(RDN) is a procedure that attempts to ameliorate the effects of heightened RSNA via ablation renal
sympathetic fibers. BP reductions associated with RDN may be attributed to decreased norepinephrine
spillover, restoration of natriuresis, increasing renal blood flow, and lowering plasma renin
activity. Early clinical trials perpetuated positive results, and enthusiasm grew exponentially. However,
recent clinical trials have called into question RDN's efficacy. Numerous limitations must be
addressed to discern the true effectiveness of RDN as a therapeutic option for RH.
Objective: We aimed to review the current understanding of RH, the anatomy of renal arteries,
physiology of RH on renal arteries, anatomical pathways of the sympathetic involved in RH, RDN
as a treatment option, and all relevant clinical trials treating RH with RDN.
Methods: We piloted a MEDLINE® database search of literature extending from 1980 to 2017, with
emphasis on the previous five years, combining keywords such as "resistant hypertension" and
"renal denervation."
Conclusion: A plethora of information is available regarding heightened RSNA leading to RH.
RDN as a possible treatment option has shown a range of results. Reconciling RDN's true efficacy
requires future trials to increased sites of nerve ablation, standardized protocol, increased anatomical
understanding per individual basis, stricter guidelines regarding study design, increased operator
experience, and integrating the use of a multielectrode catheter.
