The effect of renal denervation on arterial stiffness, central blood pressure and heart rate variability in treatment resistant essential hypertension: a substudy of a randomized sham-controlled double-blinded trial (the ReSET trial)

Renal Denervation: A New Therapy for Resistant Hypertension

The Food and Drug Administration (FDA) recently approved renal denervation to treat resistant hypertension. This procedure is a minimally invasive procedure that starts by placing a catheter in the renal artery. This catheter is used to send either radiofrequency heat or ultrasound waves to burn the superficial nerves surrounding the renal arteries while making certain no damage happens to the renal arteries themselves. This procedure is done after a renal angiogram to ensure patency of the renal artery. Each radiofrequency ablation will take 1-2 minutes, depending on the device used. The radiofrequency balloon generator requires one single application of the radiofrequency pulse. The radiofrequency generator that uses a catheter tube will need more than one pulse. The second approved option uses ultrasound to generate an electrical signal that is converted into ultrasound vibration, that occurs at the distal end of the catheter. This vibration heats the system around the nerves, disrupting the superficial nerves that communicate with the central nervous system. This will result in lowering the blood pressure. We will review the studies that led to FDA approval, and the current guidelines for use. The FDA now approves both devices.

Renal Denervation as a Novel Therapeutic Approach for Resistant Hypertension: Mechanisms, Efficacy and Future Directions

Resistant hypertension is a state characterized by sustained hypertension despite adherence to the standard pharmacological treatment with beta-blockers, calcium channel blockers, diuretics, and ACE inhibitors or ARBs. Resistant hypertension is a problem now in cardiovascular medicine because of its association with increased stroke, heart failure, kidney disease, and vision loss. Renal denervation (RDN) is an invasive treatment strategy for patients with hypertension who are unresponsive to pharmacological therapy. Therefore, this procedure has become a feasible alternative, and this review explores and compares with other possible novel options. RDN's mechanisms, efficacy, safety, and future directions are also discussed. No serious side effects have been reported in the short-term use of RDN, but some of the complications include renal stenosis and hypertensive urgencies in the long term. Despite this, RDN can benefit patients who are non-compliant with medications or are intolerant. However, it should also be pointed out that some clinical studies have not given consistent results. RDN may be employed as secondary therapy as opposed to the primary line of treatment in resistant hypertension. Subsequent studies should assess the technique's durability and establish customized approaches to deliver RDN safely while determining specific biomarkers that can predict patients' outcomes.

Renal autonomic dynamics in hypertension: how can we evaluate sympathetic activity for renal denervation?

This review explores the various pathophysiological factors influencing antihypertensive effects, involving the regulation of vascular resistance, plasma volume, cardiac function, and the autonomic nervous system, emphasizing the interconnected processes regulating blood pressure (BP). The kidney's pivotal role in BP control and its potential contribution to hypertension is complicated but important to understand the effective mechanisms of renal denervation (RDN), which may be a promising treatment for resistant hypertension. Excessive stimulation of the sympathetic nervous system or the renin-angiotensin-aldosterone system (RAAS) can elevate BP through various physiological changes, contributing to chronic hypertension. Renal sympathetic efferent nerve activation leads to elevated norepinephrine levels and subsequent cascading effects on vasoconstriction, renin release, and sodium reabsorption. RDN reduces BP in resistant hypertension by potentially disrupting sensory afferent nerves, decreasing feedback activation to the central nervous system, and reducing efferent sympathetic nerve activity in the heart and other structures. RDN may also modulate central sympathetic outflow and inhibit renal renin-angiotensin system overactivation. While evidence for RDN efficacy in hypertension is increasing, accurate patient selection becomes crucial, considering complex interactions that vary among patients. This review also discusses methods to evaluate autonomic nerve activity from the golden standard to new potential examination for finding out optimization in stimulation parameters or rigorous patient selection based on appropriate biomarkers.

Comparing the Efficacy of Renal Artery Denervation in Uncontrolled Hypertension: A Systematic Review and Network Meta-Analysis

The study aims to compare the outcomes of different renal denervation (RDN) procedures in the treatment of uncontrolled hypertension. We searched Scopus, PubMed, Web of Science, and Cochrane for RCTs evaluating different procedures of RDN for hypertension. The outcomes of this study were systolic blood pressure (SBP) daytime, diastolic blood pressure (DBP) daytime, SBP nighttime, DBP nighttime, SBP 24-hour, DBP 24-hour, SBP home, DBP home, SBP office, and DBP office. We did a frequentist network meta-analysis of 38 published RCTs evaluating the efficacy of different renal artery denervation procedures for uncontrolled hypertension compared to sham procedures or standardized stepped-care antihypertensive treatment (SSAHT). Radiofrequency (RF) alone showed a statistically significant reduction in DBP (24 hours), DBP (daytime), and DBP (nighttime): standardized mean difference (SMD): -2.01 (95% CI: (-3.34; -0.68)), SMD: -4.36 (95% CI: (-8.28; -0.44)), and SMD: -3.50 (95% CI: (-6.23; -0.76)), respectively, and showed a statistically significant reduction in SBP (24 hours), SBP (daytime), and SBP (nighttime): SMD: -3.93 (95% CI: (-6.01; -1.84)), SMD: -5.88 (95% CI: (-9.91; -1.85)), and SMD: -5.79 (95% CI: (-10.0; -1.58)), respectively. RF added to SSAHT has statistical significance in the reduction of DBP (nighttime), SBP (daytime), SBP (home), and SBP (nighttime) with a SMD of -7.63 (95% CI: (-14.21; -1.06)), SMD of -10.56 (95% CI: (-21.03; -0.08)), SMD of -23.20 (95% CI: (-36.72; -9.26)), and SMD of -14.03 (95% CI: (-25.43; -2.63)), respectively. We found that renal denervation, especially by RF, when added to SSAHT may be a promising therapeutic option for patients with treatment-resistant hypertension, particularly in cases where medication alone fails to achieve adequate blood pressure control.

Randomized Trials of Renal Denervation for Uncontrolled Hypertension: An Updated Meta-Analysis

BACKGROUND

Despite optimal medical therapy, a significant proportion of patients' blood pressure remains uncontrolled. Catheter-based renal denervation (RDN) has been proposed as a potential intervention for uncontrolled hypertension. We conducted an updated meta-analysis to assess the efficacy and safety of RDN in patients with uncontrolled hypertension, with emphasis on the differential effect of RDN in patients on and off antihypertensive medications.

METHODS AND RESULTS

Online databases were searched to identify randomized clinical trials comparing efficacy and safety of RDN versus control in patients with uncontrolled hypertension. Subgroup analyses were conducted for sham-controlled trials and studies that used RDN devices that have gained or are currently seeking US Food and Drug Administration approval. Fifteen trials with 2581 patients (RDN, 1723; sham, 858) were included. In patients off antihypertensive medications undergoing RDN, a significant reduction in 24-hour ambulatory (-3.70 [95% CI, -5.41 to -2.00] mm Hg), office (-4.76 [95% CI, -7.57 to -1.94] mm Hg), and home (-3.28 [95% CI, -5.96 to -0.61] mm Hg) systolic blood pressures was noted. In patients on antihypertensive medications, a significant reduction was observed in 24-hour ambulatory (-2.23 [95% CI, -3.56 to -0.90] mm Hg), office (-6.39 [95% CI, -11.49 to -1.30]), home (-6.08 [95% CI, -11.54 to -0.61] mm Hg), daytime (-2.62 [95% CI, -4.14 to -1.11]), and nighttime (-2.70 [95% CI, -5.13 to -0.27]) systolic blood pressures, as well as 24-hour ambulatory (-1.16 [95% CI, -1.96 to -0.35]), office (-3.17 [95% CI, -5.54 to -0.80]), and daytime (-1.47 [95% CI, -2.50 to -0.27]) diastolic blood pressures.

CONCLUSIONS

RDN significantly lowers blood pressure in patients with uncontrolled hypertension, in patients off and on antihypertensive medications, with a favorable safety profile. The efficacy of RDN was consistent in sham-controlled trials and contemporary trials using US Food and Drug Administration-approved devices.

Patient-Specific Factors Predicting Renal Denervation Response in Patients With Hypertension: A Systematic Review and Meta-Analysis

BACKGROUND

The accurate selection of patients likely to respond to renal denervation (RDN) is crucial for optimizing treatment outcomes in patients with hypertension. This systematic review was designed to evaluate patient-specific factors predicting the RDN response.

METHODS AND RESULTS

We focused on individuals with hypertension who underwent RDN. Patients were categorized based on their baseline characteristics. The primary outcome was blood pressure (BP) reduction after RDN. Both randomized controlled trials and nonrandomized studies were included. We assessed the risk of bias using corresponding tools and further employed the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the overall quality of evidence. A total of 50 studies were ultimately included in this systematic review, among which 17 studies were for meta-analysis. Higher baseline heart rate and lower pulse wave velocity were shown to be associated with significant antihypertensive efficacy of RDN on 24-hour systolic BP reduction (weighted mean difference, -4.05 [95% CI, -7.33 to -0.77]; weighted mean difference, -7.20 [95% CI, -9.79 to -4.62], respectively). In addition, based on qualitative analysis, higher baseline BP, orthostatic hypertension, impaired baroreflex sensitivity, and several biomarkers are also reported to be associated with significant BP reduction after RDN.

CONCLUSIONS

In patients with hypertension treated with the RDN, higher heart rate, and lower pulse wave velocity were associated with significant BP reduction after RDN. Other factors, including higher baseline BP, hypertensive patients with orthostatic hypertension, BP variability, impaired cardiac baroreflex sensitivity, and some biomarkers are also reported to be associated with a better BP response to RDN.

Renal Denervation in the Treatment of Resistant Hypertension and Difficult-to-Control Hypertension - Consensus Document of the Croatian Hypertension League - Croatian Society of Hypertension, Croatian Cardiac Society, Croatian Endovascular Initiative, Croatian Society for Diabetes and Metabolic Diseases, Croatian Renal Association, and Croatian Society of Family Physicians of the Croatian Medical Association

Renal denervation (RDN) as a method of treating arterial hypertension (AH) was introduced in Croatia in 2012. A multidisciplinary team and a network of hospitals that diagnose and treat patients with severe forms of AH were established, and a very strict diagnostic-treatment algorithm was prepared. At monthly meetings patients with truly resistant hypertension who were candidates for RDN were discussed. According to the 2021 ESH position statement and 2023 ESH guidelines, RDN is considered an alternative and additional, not a competitive method of treating patients with various forms of AH which must be performed by following a structured procedure and the patient's preference should be considered. In view of the changes in the global scientific community, the Croatian Hypertension League brings this consensus document on RDN conducted with radiofrequency-based catheter, the only currently available method in Croatia. In this document, exclusion and inclusion criteria are shown, as well as three groups of patients in whom RDN could be considered. The new diagnostic-treatment algorithm is prepared and follow-up procedure is explained. In Croatia, RDN is reimbursed by the national insurance company, thus pharmacoeconomic analyses is also shown. Criteria required by an individual centre to be approved of RDN are listed, and plans for prospective research on RDN in Croatia, including the Croatian registry for RDN, are discussed.

A systematic review, meta-analysis, and meta regression of the sham controlled renal denervation randomized controlled trials

Renal denervation (RD) has been investigated as a novel blood pressure (BP) lowering treatment for hypertension. The primary objective of this meta-analysis was to assess the efficacy of RD and factors that may associate with treatment effect heterogeneity. The primary outcomes were raw mean differences (RMD) in 24-hour ambulatory, daytime ambulatory, nighttime, and office systolic BP (SBP) and diastolic BP (DBP) between sham control and RD. A prespecified subgroup analysis was performed comparing studies with follow-up less than versus greater than 4 months. If inter-study heterogeneity was found for any of the above outcomes, additional analyses were performed to assess potential moderator variables. Ten sham-controlled randomized trials were identified and included 1,544 participants, followed for a mean of 4.20 months. RD was associated with a statistically significant reduction in all SBP and DBP measures except for nighttime SBP (-2.64 mmHg; 95% confidence interval (CI) -5.84 to 0.56, p = 0.11) and nighttime DBP (- 1.21 mmHg; 95% CI -3.17 to 0.75, p = 0.23). Mild to moderate inter-study heterogeneity was identified for three outcomes (office SBP and nighttime SBP and DBP). Studies that followed patients for longer than 4 months had numerically lower reductions in most BP outcomes; however, there were no statistically significant interactions between subgroups. Compared to a sham procedure, RD was associated with statistically significant reductions in most measures of SBP and DBP that were within bounds of what would be expected from standard blood pressure lowering medications.

Predicting Renal Denervation Response in Resistant High Blood Pressure by Arterial Stiffness Assessment: A Systematic Review

Background: Accurately selecting hypertensive candidates for renal denervation (RDN) therapy is required, as one-third of patients who undergo RDN are non-responders. We aimed to systematically review the literature on RDN response prediction using arterial stiffness assessment, optimizing the selection of patients referred for interventional blood pressure lowering procedures. Methods: A literature search was performed in MEDLINE, Embase, Scopus, and Cochrane databases to retrieve potential eligible studies from the inception to 30 June 2022. Results: Ten studies were finally included in this systematic review. Studies consistently documented that invasive pulse wave velocity (PWV) was correlated with RDN’s significant success. Nevertheless, non-invasive ambulatory arterial stiffness index and PWV derived from ambulatory blood pressure monitoring were independent predictors of blood pressure response (p = 0.04 and p < 0.0001). In some studies, magnetic resonance imaging parameters of arterial stiffness (ascending aortic distensibility, total arterial compliance) were correlated with blood pressure reduction (AUC = 0.828, p = 0.006). Conclusions: Assessing arterial stiffness prior to RDN predicted procedural success, since stiffness parameters were strongly correlated with a significant blood pressure response. Our endeavor should be tackled as a step forward in selecting appropriate hypertensive patients scheduled for RDN therapy. Non-invasive measurements could be an alternative to invasive parameters for response prediction.

The autonomic balance of heart rhythm complexity after renal artery denervation: insight from entropy of entropy and average entropy analysis

Background

The current method to evaluate the autonomic balance after renal denervation (RDN) relies on heart rate variability (HRV). However, parameters of HRV were not always predictive of response to RDN. Therefore, the complexity and disorder of heart rhythm, measured by entropy of entropy (EoE) and average entropy (AE), have been used to analyze autonomic dysfunction. This study evaluated the dynamic changes in autonomic status after RDN via EoE and AE analysis.

Methods

Five patients were prospectively enrolled in the Global SYMPLICITY Registry from 2020 to 2021. 24-h Holter and ambulatory blood pressure monitoring (ABPM) was performed at baseline and 3 months after RDN procedures. The autonomic status was analyzed using the entropy-based AE and EoE analysis and the conventional HRV-based low frequency (LF), high frequency (HF), and LF/HF.

Results

After RDN, the ABPM of all patients showed a significant reduction in blood pressure (BP) and heart rate. Only AE and HF values of all patients had consistent changes after RDN (p < 0.05). The spearman rank-order correlation coefficient of AE vs. HF was 0.86, but AE had a lower coefficient of variation than HF.

Conclusions

Monitoring the AE and EoE analysis could be an alternative to interpreting autonomic status. In addition, a relative change of autonomic tone, especially an increasing parasympathetic activity, could restore autonomic balance after RDN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12938-022-00999-4.

Effect of Renal Denervation for the Management of Heart Rate in Patients With Hypertension: A Systematic Review and Meta-Analysis

Objective:

The effect of renal denervation (RDN) on heart rate (HR) in patients with hypertension had been investigated in many studies, but the results were inconsistent. This meta-analysis was performed to evaluate the efficacy of RDN on HR control.

Methods:

Databases, such as PubMed, EMBASE, Cochrane, and ClinicalTrials.gov, were searched until September 2021. Randomized controlled trials (RCTs) or non-RCTs of RDN in hypertensive patients with outcome indicators, such as HR, were selected. Weighted mean difference (WMD) was calculated for evaluating the changes in HR from baseline using fixed-effects or random-effects models. The Spearman's correlation coefficients were used to identify the relationship between the changes of HR and systolic blood pressure (SBP).

Results:

In the current meta-analysis, 681 subjects from 16 individual studies were included. This study showed that RDN could reduce office HR in patients with hypertension [WMD = −1.93 (95% CI: −3.00 to −0.85, p < 0.001)]. In addition, 24-h HR and daytime HR were decreased after RDN [WMD = −1.73 (95% CI: −3.51 to −0.31, p = 0.017) and −2.67 (95% CI: −5.02 to −0.32, p = 0.026) respectively], but nighttime HR was not significantly influenced by RDN (WMD = −2.08, 95% CI: −4.57 to 0.42, p = 0.103). We found that the reduction of HR was highly related to the decrease of SBP (r = 0.658, p < 0.05).

Conclusion:

Renal denervation could reduce office, 24-h, and daytime HR, but does not affect nighttime HR. And the effect is highly associated with blood pressure (BP) control.

Systematic Review Registration:

https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42021283065.

Renal denervation for resistant hypertension

BACKGROUND

Resistant hypertension is highly prevalent among the general hypertensive population and the clinical management of this condition remains problematic. Different approaches, including a more intensified antihypertensive therapy, lifestyle modifications or both, have largely failed to improve patients' outcomes and to reduce cardiovascular and renal risk. As renal sympathetic hyperactivity is a major driver of resistant hypertension, in the last decade renal sympathetic ablation (renal denervation) has been proposed as a possible therapeutic alternative to treat this condition.

OBJECTIVES

We sought to evaluate the short- and long-term effects of renal denervation in individuals with resistant hypertension on clinical end points, including fatal and non-fatal cardiovascular events, all-cause mortality, hospital admissions, quality of life, blood pressure control, left ventricular hypertrophy, cardiovascular and metabolic profile and kidney function, as well as the potential adverse events related to the procedure.

SEARCH METHODS

For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to 3 November 2020: Cochrane Hypertension's Specialised Register, CENTRAL (2020, Issue 11), Ovid MEDLINE, and Ovid Embase. The World Health Organization International Clinical Trials Registry Platform (via CENTRAL) and the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov were searched for ongoing trials. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that compared renal denervation to standard therapy or sham procedure to treat resistant hypertension, without language restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed study risk of bias. We summarised treatment effects on available clinical outcomes and adverse events using random-effects meta-analyses. We assessed heterogeneity in estimated treatment effects using Chi² and I² statistics. We calculated summary treatment estimates as a mean difference (MD) or standardised mean difference (SMD) for continuous outcomes, and a risk ratio (RR) for dichotomous outcomes, together with their 95% confidence intervals (CI). Certainty of evidence has been assessed using the GRADE approach.

MAIN RESULTS

We found 15 eligible studies (1416 participants). In four studies, renal denervation was compared to sham procedure; in the remaining studies, renal denervation was tested against standard or intensified antihypertensive therapy. Most studies had unclear or high risk of bias for allocation concealment and blinding.  When compared to control, there was low-certainty evidence that renal denervation had little or no effect on the risk of myocardial infarction (4 studies, 742 participants; RR 1.31, 95% CI 0.45 to 3.84), ischaemic stroke (5 studies, 892 participants; RR 0.98, 95% CI 0.33 to 2.95), unstable angina (3 studies, 270 participants; RR 0.51, 95% CI 0.09 to 2.89) or hospitalisation (3 studies, 743 participants; RR 1.24, 95% CI 0.50 to 3.11). Based on moderate-certainty evidence, renal denervation may reduce 24-hour ambulatory blood pressure monitoring (ABPM) systolic BP (9 studies, 1045 participants; MD -5.29 mmHg, 95% CI -10.46 to -0.13), ABPM diastolic BP (8 studies, 1004 participants; MD -3.75 mmHg, 95% CI -7.10 to -0.39) and office diastolic BP (8 studies, 1049 participants; MD -4.61 mmHg, 95% CI -8.23 to -0.99). Conversely, this procedure had little or no effect on office systolic BP (10 studies, 1090 participants; MD -5.92 mmHg, 95% CI -12.94 to 1.10). Moderate-certainty evidence suggested that renal denervation may not reduce serum creatinine (5 studies, 721 participants, MD 0.03 mg/dL, 95% CI -0.06 to 0.13) and may not increase the estimated glomerular filtration rate (eGFR) or creatinine clearance (6 studies, 822 participants; MD -2.56 mL/min, 95% CI -7.53 to 2.42).  AUTHORS' CONCLUSIONS: In patients with resistant hypertension, there is low-certainty evidence that renal denervation does not improve major cardiovascular outomes and renal function. Conversely, moderate-certainty evidence exists that it may improve 24h ABPM and diastolic office-measured BP. Future trials measuring patient-centred instead of surrogate outcomes, with longer follow-up periods, larger sample size and more standardised procedural methods are necessary to clarify the utility of this procedure in this population.

Large Artery Stiffness: A Companion to the 2015 AHA Science Statement on Arterial Stiffness

Large artery stiffness (LAS) has proven to be an independent risk factor for cardiovascular disease and mortality. Nevertheless, the position of current hypertension guidelines regarding the usefulness of assessing LAS differs across different continents. In general, European Guidelines recognize pulse wave velocity (PWV) as a marker of target organ damage but do not recommend its systematic use in general population. Asian guidelines consider PWV as a recommended test at diagnosis of hypertension, in contrast to North American guidelines that do not state any position about its usefulness. However, PWV predicts cardiovascular events, and several studies have shown that it improves risk classification adjusting for established risk factors especially for intermediate-risk patients. Finally, some advances have been made related to treatments affecting LAS. Dietary interventions such as sodium restriction and exercise-based interventions have a modest effect in reducing LAS. Pharmacological interventions, such as statins, or more recent advances with mineralocorticoid blocker seem to have a beneficial effect. Last, controversial effects of renal denervation on LAS have been found. Our goal here is to update the reader on LAS on these areas since the 2015 American Heart Association Scientific Statement.

Effects of renal denervation on the expression profile of circular RNA in the serum of patients with resistant hypertension

OBJECTIVE

Renal denervation (RDN) is a new treatment option for resistant hypertension (RH), although it has been shown that reduced sympathetic nerve activity after RDN is the main cause of blood pressure decline. In view of the possible correlation between circRNA and hypertension and the metabolic state of the body after RDN, we investigated the potential role of circRNA in RDN treatment of RH.

METHODS

Serum samples of patients with RH were collected before and 48 h after RDN. We explored the mechanism underlying RDN with high-throughput integration of circRNA data.

RESULTS

There were 338 circRNAs that were differentiated before and after RDN; 170 were upregulated and 168 were downregulated (≥1.2-fold, P < 0.05), and the expression of five of them changed significantly (≥1.5-fold, P < 0.05). We used reverse transcription-quantitative polymerase chain reaction to confirm these results in 13 other patients with RH. hsa_circRNA_000367 was upregulated and hsa_circRNA_405119 was downregulated after RDN. We predicted their downstream miRNA-mRNA network and analyzed their putative function via the circRNA-miRNA-mRNA pathway. GO/KEGG analysis showed that their functional annotation may be related to nerve injury and hypertension. We used the Venn Diagram Generator to obtain the intersection of predicted target and sympathetic nerve-related genes (from GeneCards website).

CONCLUSION

The mechanism underlying RDN may be closely related to upregulated hsa_circRNA_000367 or downregulated hsa_circRNA_405119 and involve regulated multiple pathways and multiple cellular and molecular biological processes. These circRNAs may potentially be used as treatment effect biomarkers in RDN.

The state of renal sympathetic denervation for the management of patients with hypertension: A systematic review and meta-analysis

BACKGROUND

Sympathetic nervous system plays a central role in the development and persistence of essential hypertension. In recent years renal sympathetic denervation (RSD) has emerged as a promising option for the treatment of patients with hypertension.

METHODS

We conducted a literature search of PubMed, EMBASE, Cochrane library and Clinicaltrials.gov from inception through April 20, 2020. Outcomes of interest were change in 24-hour ambulatory systolic (ASBP) or diastolic blood pressure (ADBP) and change in office systolic (OSBP) or diastolic blood pressure (ODBP). We pooled data from randomized controlled trials (RCTS) comparing RSD to sham procedures in the management of hypertension using the random effect model.

RESULTS

A total of 1,363 patients from eight studies were included in the current meta-analysis. The mean age of the included patients was 56 ± 2.6 years, 29% were women and the median duration of maximum follow up was 6-month (range 3-12 month). There was more reduction favoring RSD in ASBP (Weighted mean difference [WMD] -3.55; 95% CI -4.91 - -2.19, p < .001, I² = 0%), ADBP (WMD -1.87; 95% CI -3.07 - -0.66, p = .002, I² = 43%), OSBP (WMD -5.5; 95% CI -7.59 - -3.40, p < .001, I² = 7%) and ODBP (WMD -3.20; 95% CI -4.47 - -1.94, p < .001, I² = 14%).

CONCLUSION

The use of RSD for the management of hypertension resulted in effective reduction in the ambulatory and office blood pressure compared to sham procedure. Adequately powered RCTs of RSD are needed to confirm safety, reproducibility and assess the impact on clinical outcomes.

Arterial Destiffening Starts Early after Renal Artery Denervation

Introduction

Renal artery denervation (RDN) is a new widely discussed method in treatment of hypertension. Most of the RDN studies assessed BP and arterial changes 3 and 6 months after the procedure, but there is a lack of trials that investigated early changes after RDN.

Aim

To investigate aortic stiffness 24-48 hours after the procedure and thus to examine whether RDN might have an early additive value for a cardiovascular risk decline beyond the lowering of blood pressure.

Methods

RDN was performed for 73 patients with resistant hypertension. Arterial stiffness and central haemodynamics were measured before the procedure, the next day after the procedure, and subsequently after 1, 3, 6, and 12 months.

Results

Within 48 hours, RDN significantly reduced aortic pulse wave velocity (AoPWV) from 11.3±2.7 to 10.3±2.6 m/s (p=0.001); reduction was sustained at months 1, 3, 6, and 12. Early changes in the AoPWV value did not correlate with changes in office systolic or diastolic BP (p=0.45; p=0.33). Furthermore, the higher the initial AoPWV value, the greater the reduction of AoPWV observed after 6 months: Q₁ 8.4±1, Δ0.05±1.6 / Q₂ 10.1±0.4, Δ1.1±1.4 / Q₃ 12.2±0.8, Δ1.8±1.7 / Q₄ 15.3±1.7, Δ2.8±2.1 (p=0.002).

Conclusions

Early and sustained effects on AoPWV observed in our study suggest that RDN may have additional effects on reducing arterial stiffness and cardiovascular risk.