Clinical benefits and safety of renal denervation in severe arterial hypertension: A long‐term follow‐up study

Effects of renal denervation on blood pressure in patients with hypertension: a latest systematic review and meta-analysis of randomized sham-controlled trials

The efficacy of renal denervation (RDN) has been controversial, but recent randomized sham-controlled trials demonstrated significant blood pressure reductions after RDN in patients with hypertension. We conducted a systematic review and updated meta-analysis to evaluate the effects of RDN on ambulatory and office blood pressures in patients with hypertension. Databases were searched up to 15 November 2023 to identify randomized, sham-controlled trials of RDN. The primary endpoint was change in 24 h ambulatory systolic blood pressure (SBP) with RDN versus sham control. The secondary endpoints were changes in 24 h ambulatory diastolic blood pressure, daytime and nighttime blood pressure (BP), office BP, and home BP. A sub-analysis determined outcomes by medication, procedure, and device. From twelve trials, 2222 patients with hypertension were randomized to undergo RDN (n = 1295) or a sham procedure (n = 927). At 2-6 months after treatment, RDN significantly reduced 24 h ambulatory SBP by 2.81 mmHg (95% confidence interval: -4.09, -1.53; p < 0.001) compared with the sham procedure. RDN also reduced daytime SBP by 3.17 mmHg (- 4.75, - 1.58; p < 0.001), nighttime SBP by 3.41 mmHg (- 4.69, - 2.13; p < 0.001), office SBP by 4.95 mmHg (- 6.37, - 3.54; p < 0.001), and home SBP by 4.64 mmHg (- 7.44, - 1.84; p = 0.001) versus the sham control group. There were no significant differences in the magnitude of BP reduction between first- and second-generation trials, between devices, or between with or without medication. These data from randomized sham-controlled trials showed that RDN significantly reduced all blood pressure metrics in medicated or unmedicated patients with hypertension, including resistant/uncontrolled hypertension.

Long-Term Blood Pressure Reductions Following Catheter-Based Renal Denervation: A Systematic Review and Meta-Analysis

BACKGROUND

Renal denervation is a recognized adjunct therapy for hypertension with clinically significant blood pressure (BP)-lowering effects. Long-term follow-up data are critical to ascertain durability of the effect and safety. Aside from the 36-month follow-up data available from randomized control trials, recent cohort analyses extended follow-up out to 10 years. We sought to analyze study-level data and quantify the ambulatory BP reduction of renal denervation across contemporary randomized sham-controlled trials and available long-term follow-up data up to 10 years from observational studies.

METHODS

A systematic review was performed with data from 4 observational studies with follow-up out to 10 years and 2 randomized controlled trials meeting search and inclusion criteria with follow-up data out to 36 months. Study-level data were extracted and compared statistically.

RESULTS

In 2 contemporary randomized controlled trials with 36-month follow-up, an average sham-adjusted ambulatory systolic BP reduction of -12.7±4.5 mm Hg from baseline was observed (P=0.05). Likewise, a -14.8±3.4 mm Hg ambulatory systolic BP reduction was found across observational studies with a mean long-term follow-up of 7.7±2.8 years (range, 3.5-9.4 years; P=0.0051). The observed reduction in estimated glomerular filtration rate across the long-term follow-up was in line with the predicted age-related decline. Antihypertensive drug burden was similar at baseline and follow-up.

CONCLUSIONS

Renal denervation is associated with a significant and clinically meaningful reduction in ambulatory systolic BP in both contemporary randomized sham-controlled trials up to 36 months and observational cohort studies up to 10 years without adverse consequences on renal function.

Clinical event reductions in high-risk patients after renal denervation projected from the global SYMPLICITY registry

AIMS

Renal denervation has been shown to lower blood pressure in sham-controlled trials and represents a device-based treatment option for hypertension. We sought to project clinical event reductions after radiofrequency renal denervation using a novel modelling approach.

METHODS AND RESULTS

The Global SYMPLICITY Registry is a global, prospective all-comer registry to evaluate safety and efficacy after renal denervation. For this analysis, change in office systolic blood pressure from baseline was calculated from reported follow-up in the Global SYMPLICITY Registry. Relative risks for death and other cardiovascular events as well as numbers needed to treat for event avoidance were obtained for the respective blood pressure reductions based on previously reported meta-regression analyses for the full cohort and high-risk subgroups including type 2 diabetes, chronic kidney disease, resistant hypertension, and high basal cardiovascular risk. Average baseline office systolic blood pressure and reduction estimates for the full cohort (N = 2651) were 166±25 and -14.8 ± 0.4 mmHg, respectively. Mean reductions in blood pressure ranged from -11.0--21.8 mmHg for the studied high-risk subgroups. Projected relative risks ranged from 0.57 for stroke in the resistant hypertension cohort to 0.92 for death in the diabetes cohort. Significant absolute reductions in major adverse cardiovascular events over 3 years compared with the projected control (8.6 ± 0.7% observed vs. 11.7 ± 0.9% for projected control; P < 0.01) were primarily due to reduced stroke incidence. The robustness of findings was confirmed in sensitivity and scenario analyses.

CONCLUSION

Model-based projections suggest radiofrequency renal denervation for patients with uncontrolled hypertension adds considerable clinical benefit across a spectrum of different cohort characteristics.

Safety and efficacy of renal sympathetic denervation: a 9-year long-term follow-up of 24-hour ambulatory blood pressure measurements

Background

Renal sympathetic denervation (RDN) has been shown to lower arterial blood pressure both in the presence and in the absence of antihypertensive medication in an observation period of up to 3 years. However, long-term results beyond 3 years are scarcely reported.

Methods

We performed a long-term follow-up on patients who were previously enrolled in a local renal denervation registry and who underwent radiofrequency RDN with the Symplicity Flex® renal denervation system between 2011 and 2014. The patients were assessed to evaluate their renal function by performing 24-hour ambulatory blood pressure measurement (ABPM), recording their medical history, and conducting laboratory tests.

Results

Ambulatory blood pressure readings for 24 h were available for 72 patients at long-term follow-up (FU) [9.3 years (IQR: 8.5-10.1)]. We found a significant reduction of ABP from 150.1/86.1 ± 16.9/12.0 mmHg at baseline to 138.3/77.1 ± 16.5/11.1 mmHg at long-term FU (P < 0.001 for both systolic and diastolic ABP). The number of antihypertensive medications used by the patients significantly decreased from 5.4 ± 1.5 at baseline to 4.8 ± 1.6 at long-term FU (P < 0.01). Renal function showed a significant but expected age-associated decrease in the eGFR from 87.8 (IQR: 81.0-100.0) to 72.5 (IQR: 55.8-86.8) ml/min/1.73 m² (P < 0.01) in patients with an initial eGFR > 60 ml/min/1.73 m², while a non-significant decrease was observed in patients with an initial eGFR < 60 ml/min/1.73 m² at long-term FU [56.0 (IQR: 40.9-58.4) vs. 39.0 (IQR: 13.5-56.3) ml/min/1.73 m²].

Conclusions

RDN was accompanied by a long-lasting reduction in blood pressure with a concomitant reduction in antihypertensive medication. No negative effects could be detected, especially with regard to renal function.

Effect of Renal Denervation on the Plasma Adiponectin Concentration in Patients with Resistant Hypertension

(1) Introduction: Adiponectin is synthetized by white adipose tissue and has anti-diabetic, anti-atherosclerotic, anti-thrombotic, anti-inflammatory, and cardioprotective properties. In patients with arterial hypertension, plasma concentration of adiponectin is lower than in healthy subjects. Renal denervation, i.e., percutaneous ablation of fibers from the sympathetic nervous system located in the wall of the renal arteries by radio frequency waves, is a method of resistant arterial hypertension treatment. (2) The aim of this single center, interventional, clinical study was to assess the effect of renal denervation on the plasma adiponectin concentration in patients with resistant arterial hypertension. (3) Materials and methods: 28 patients (13 women, 15 men) aged 54.4 ± 9.2 years with resistant hypertension who underwent renal denervation using Simplicity catheters (Medtronic, Inc., Northridge, CA, USA) were enrolled in the study. Plasma adiponectin concentration was determined using the Human Adiponectin ELISA Kit (Otsuka Pharmaceutical Co, Tokyo, Japan) before the renal denervation and 6 and 12 months after this procedure. (4) Results: Blood pressure (BP) values before renal denervation and 6 and 12 months after this procedure were as follows: systolic BP 190.4 ± 24.5, 160.8 ± 14.5, 155.7 ± 17.9 mmHg (p < 0.001) and diastolic BP 111.7 ± 18.9, 88.9 ± 8.3, 91.2 + 10.2 mmHg (p < 0.001), respectively. Body mass index (BMI) before renal denervation, 6 and 12 months after this procedure were 31.5 ± 4.2, 30.5 ± 4.4, 30.2 ± 4.0 kg/m2, (p = 0.057), respectively. Plasma adiponectin concentration before the renal denervation and 6 and 12 months after this procedure were 4.79 (3.95; 9.49), 7.58 (5.04; 9.51), 6.62 (4.57; 11.65) [µg/mL] (p = 0.007), respectively. (5) Conclusions: Plasma adiponectin concentration increases significantly after successful renal denervation in patients with resistant hypertension. Higher plasma adiponectin concentration may participate—beyond blood pressure reduction—in the cardiovascular benefits related to successful renal denervation; however’ clinical consequences of these results need further investigations.

Renal denervation in the antihypertensive arsenal - knowns and known unknowns

Even though it has been more than a decade since renal denervation (RDN) was first used to treat hypertension and an intense effort on researching this therapy has been made, it is still not clear how RDN fits into the antihypertensive arsenal. There is no question that RDN lowers blood pressure (BP), it does so to an extent at best corresponding to one antihypertensive drug. The procedure has an excellent safety record. However, it remains clinically impossible to predict whose BP responds to RDN and whose does not. Long-term efficacy data on BP reduction are still unconvincing despite the recent results in the SPYRAL HTN-ON MED trial; experimental studies indicate that reinnervation is occurring after RDN. Although BP is an acceptable surrogate endpoint, there is complete lack of outcome data with RDN. Clear indications for RDN are lacking although patients with resistant hypertension, those with documented increase in activity of the sympathetic system and perhaps those who desire to take fewest medication may be considered.

Main Renal Artery Plus Branch Ablation in the Treatment of Resistant Hypertension with Renal Denervation

Objective: To study the safety and efficacy of denervation of renal artery branches in the treatment of resistant hypertension.Methods: Sixty patients with resistant hypertension were enrolled. The patients were randomly assigned to the main renal artery plus branch ablation group or the main renal artery ablation group. The clinical data and operation-related parameters, including number of ablation points, temperature, and average energy, were recorded. Ambulatory blood pressure was taken for all patients at the baseline and at 6 months after treatment. Office blood pressure was recorded before treatment and after treatment every 3 months for 2 years.Results: Sixty patients with resistant hypertension were enrolled in this study. There were 30 patients in each group. Angiography was performed after ablation. No renal artery complications, such as stenosis and dissection, occurred in the two groups. There was no significant difference in age, sex, BMI, comorbid disease, and medication between the two groups (P>0.05). The number of ablation points for the main renal artery plus branch ablation group was greater than that for the main renal artery ablation group. The office blood pressure and 24-hour blood pressure were significantly lower 6 months after treatment than before treatment in both groups (P<0.05). Office blood pressure in the main renal artery plus branch ablation group was lower than that in the main renal artery ablation group during the 3‐12-month follow-up period, with a statistical difference. However, as the follow-up time increased, the difference disappeared.Conclusion: The results of this study show that main renal artery plus branch ablation is a safe interventional method, but there was no obvious advantage on long-term follow-up compared with only main renal artery ablation.

Efficacy and safety of renal denervation for hypertension in patients with chronic kidney disease: a meta-analysis

BACKGROUND

Renal denervation (RDN) is a new treatment for hypertension in patients with chronic kidney disease (CKD), but its efficacy is still debated. This meta-analysis aimed to evaluate the efficacy and safety of RDN for hypertension in patients with CKD.

METHODS

PubMed, Web of Science, EMBASE, and Ovid databases were searched for relevant studies published. We performed both fixed- and random-effects meta-analyses of the changes in blood pressure, estimated glomerular filtration rate (eGFR), and urinary albumin-to-creatinine ratio (UACR) after RDN.

RESULTS

The meta-analysis included 238 patients from 11 single-center, non-randomized, uncontrolled studies. Office blood pressure and 24-hour ambulatory blood pressure (24 h-ABP) showed a significant reduction 1 month after RDN (p < 0.05). This decrease of 24 h-ABP persisted for 24 months after RDN showed difference systolic blood pressure (p < 0.001) and diastolic blood pressure (p = 0.001). The 24 h-ABP exhibited a similar trend in the subgroup analysis. eGFR measurements obtained at each time point of analysis after RDN were not significantly different from those obtained before (p > 0.05). UACR levels were significantly reduced at 3 months and 6 months after RDN (p < 0.001). After RDN, the heart rate showed no significant changes (p > 0.05), and few major complications were encountered.

CONCLUSIONS

The meta-analysis showed that RDN may be effective and safe for treating CKD patients with hypertension. Well-designed randomized controlled trials of RDN are urgently needed to confirm the safety and reproducibility of RDN and to assess its impact on clinical outcomes.