Cardiac magnetic resonance assessment of central and peripheral vascular function in patients undergoing renal sympathetic denervation as predictor for blood pressure response

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.

Skin sodium content as a predictor of blood pressure response to renal denervation

Patients with treatment resistant hypertension (TRH) are known to have elevated sodium (Na) content in muscle and skin. Renal denervation (RDN) emerged as an adjacent therapeutic option in this group of patients. This analysis aimed at evaluating whether tissue Na content predicts blood pressure (BP) response after RDN in patients with TRH. Radiofrequency-device based RDN was performed in 58 patients with uncontrolled TRH. Office and 24-h ambulatory BP were measured at baseline and after 6 months. To assess tissue Na content Na magnetic resonance imaging (Na-MRI) was performed at baseline prior to RDN. We splitted the study cohort into responders and non-responders based on the median of systolic 24-h ambulatory blood pressure (ABP) reduction after 6 months and evaluated the association between BP response to RDN and tissue Na content in skin and muscle. The study was registered at http://www.clinicaltrials.gov (NCT01687725). Six months after RDN 24-h ABP decreased by -8.6/-4.7 mmHg. BP-Responders were characterized by the following parameters: low tissue sodium content in the skin (p = 0.040), female gender (p = 0.027), intake of aldosterone antagonists (p = 0.032), high baseline 24-h night-time heart rate (p = 0.045) and high LDL cholesterol (p < 0.001). These results remained significant after adjustment for baseline 24-h systolic BP. Similar results were obtained when the median of day-time and night-time ABP reduction after 6 months were used as cut-off criteria for defining BP response to RDN. We conclude that in addition to clinical factors including baseline 24-h ABP Na-MRI may assist to select patients with uncontrolled TRH for RDN treatment.

Association between renal sympathetic denervation and arterial stiffness: the ASORAS study

OBJECTIVES

Renal sympathetic denervation (RDN) reduces blood pressure (BP). However, one out of three patients does not exhibit a significant BP response to the therapy. This study investigates the association between noninvasive vascular stiffness indices and RDN-mediated BP reduction.

METHODS

In this prospective, single-arm pilot study, patients with systolic office BP at least 140 mmHg, mean 24-h systolic ambulatory blood pressure (ABP) at least 130 mmHg and at least three prescribed antihypertensive drugs underwent radiofrequency RDN. The primary efficacy endpoint was temporal evolution of mean 24-h systolic ABP throughout 1-year post RDN (measured at baseline and 3-6-12 months). Effect modification was studied for baseline ultrasound carotid-femoral and magnetic resonance (MR) pulse wave velocity (PWV), MR aortic distensibility, cardiac MR left ventricular parameters and clinical variables. Statistical analyses were performed using linear mixed-effects models, and effect modification was assessed using interaction terms.

RESULTS

Thirty patients (mean age 62.5 ± 10.7 years, 50% women) with mean 24-h ABP 146.7/80.8 ± 13.7/12.0 mmHg were enrolled. Following RDN, mean 24-h systolic ABP changed with -8.4 (95% CI: -14.5 to -2.3) mmHg/year ( P  = 0.007). Independent effect modifiers were CF-PWV [+2.7 (0.3 to 5.1) mmHg/year change in outcome for every m/s increase in CF-PWV; P  = 0.03], daytime diastolic ABP [-0.4 (-0.8 to 0.0) mmHg/year per mmHg; P  = 0.03], age [+0.6 (0.2 to 1.0) mmHg/year per year of age; P  = 0.006], female sex [-14.0 (-23.1 to -5.0) mmHg/year as compared with men; P  = 0.003] and BMI [+1.2 (0.1 to 2.2) mmHg/year per kg/m 2 ; P  = 0.04].

CONCLUSION

Higher CF-PWV at baseline was associated with a smaller reduction in systolic ABP following RDN. These findings could contribute to improve identification of RDN responders.

Assessment of arterial stiffness to predict blood pressure response to renal sympathetic denervation

BACKGROUND

Recent trials support the efficacy of renal sympathetic denervation (RDN) to reduce blood pressure (BP). Nevertheless, about one third of patients are considered non-responders to RDN. Previous retrospective analyses suggest arterial stiffness could predict BP response to RDN.

AIMS

We prospectively assessed the potential of invasive pulse wave velocity (iPWV) to predict BP response to RDN. Additionally, we aimed to establish non-invasive models based on arterial stiffness to predict BP response to RDN.

METHODS

 iPWV, magnetic resonance imaging-based markers of arterial stiffness and the carotid-femoral pulse wave velocity were recorded prior to RDN in patients with treatment resistant hypertension. Changes in daytime BP after 3 months were analysed according to the prespecified iPWV cut-off (14.4 m/s). Regression analyses were used to establish models for non-invasive prediction of BP response. Results were compared to iPWV as reference and were then validated in an external patient cohort.

RESULTS

Eighty patients underwent stiffness assessment before RDN. After 3 months, systolic 24h and daytime BP were reduced by 13.6±9.8 mmHg and 14.7±10.6 mmHg in patients with low iPWV, versus 6.2±13.3 mmHg and 6.3±12.8 mmHg in those with high iPWV (p<0.001 for both). Upon regression analysis, logarithmic ascending aortic distensibility and systolic baseline BP independently predicted BP change at follow-up. Both were confirmed in the validation cohort.

CONCLUSIONS

 iPWV is an independent predictor for BP response after RDN. In addition, BP change prediction following RDN using non-invasive measures is feasible. This could facilitate patient selection for RDN treatment.

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.

Present Evidence of Determinants to Predict the Efficacy of Renal Denervation

Sympathetic overactivation is one of the main contributors to development and progress of hypertension. Renal denervation (RDN) has been evidenced by series of clinical trials for its efficacy and safety to treat overactivated sympathetic nervous system induced diseases. However, the results were inconsistent and not all patients benefited from RDN. Appropriate patient selection and intraoperative factors to improve the efficacy of RDN need to be solved urgently. Over the decade, research studies on the correlations between indicators and the antihypertensive effects have been conducted and made a fairly well progress. Herein, we comprehensively reviewed the research studies on how to make RDN more predictable or improve the efficacy of RDN and summarized these potential indicators or devices which might be applied in clinical settings.

Changes in Plasma Renin Activity After Renal Artery Sympathetic Denervation

BACKGROUND

The renin-angiotensin-aldosterone system plays a key role in blood pressure (BP) regulation and is the target of several antihypertensive medications. Renal denervation (RDN) is thought to interrupt the sympathetic-mediated neurohormonal pathway as part of its mechanism of action to reduce BP.

OBJECTIVES

The purpose of this study was to evaluate plasma renin activity (PRA) and aldosterone before and after RDN and to assess whether these baseline neuroendocrine markers predict response to RDN.

METHODS

Analyses were conducted in patients with confirmed absence of antihypertensive medication. Aldosterone and PRA levels were compared at baseline and 3 months post-procedure for RDN and sham control groups. Patients in the SPYRAL HTN-OFF MED Pivotal trial were separated into 2 groups, those with baseline PRA ≥0.65 ng/ml/h (n = 110) versus <0.65 ng/ml/h (n = 116). Follow-up treatment differences between RDN and sham control groups were adjusted for baseline values using multivariable linear regression models.

RESULTS

Baseline PRA was similar between RDN and control groups (1.0 ± 1.1 ng/ml/h vs. 1.1 ± 1.1 ng/ml/h; p = 0.37). Change in PRA at 3 months from baseline was significantly greater for RDN compared with control subjects (-0.2 ± 1.0 ng/ml/h; p = 0.019 vs. 0.1 ± 0.9 ng/ml/h; p = 0.14), p = 0.001 for RDN versus control subjects, and similar differences were seen for aldosterone: RDN compared with control subjects (-1.2 ± 6.4 ng/dl; p = 0.04 vs. 0.4 ± 5.4 ng/dl; p = 0.40), p = 0.011. Treatment differences at 3 months in 24-h and office systolic blood pressure (SBP) for RDN versus control patients were significantly greater for patients with baseline PRA ≥0.65 ng/ml/h versus <0.65 ng/ml/h, despite similar baseline BP. Differences in office SBP changes according to baseline PRA were also observed earlier at 2 weeks post-RDN.

CONCLUSIONS

Plasma renin activity and aldosterone levels for RDN patients were significantly reduced at 3 months when compared with baseline as well as when compared with sham control. Higher baseline PRA levels were associated with a significantly greater reduction in office and 24-h SBP. (SPYRAL PIVOTAL - SPYRAL HTN-OFF MED Study; NCT02439749).

A Three-Arm Randomized Trial of Different Renal Denervation Devices and Techniques in Patients With Resistant Hypertension (RADIOSOUND-HTN)

BACKGROUND

Both radiofrequency and ultrasound endovascular renal sympathetic denervation (RDN) have proven clinical efficacy for the treatment of hypertension. We performed a head-to-head comparison of these technologies.

METHODS

Patients with resistant hypertension were randomly assigned in a 1:1:1 manner to receive either treatment with (1) radiofrequency RDN of the main renal arteries; (2) radiofrequency RDN of the main renal arteries, side branches, and accessories; or (3) an endovascular ultrasound-based RDN of the main renal artery. The primary end point was change in systolic daytime ambulatory blood pressure at 3 months.

RESULTS

Between June 2015 and June 2018, 120 patients were enrolled (mean age, 64±9 years±SD; mean daytime blood pressure, 153/86±12/13 mm Hg). Of these, 39 were randomly assigned to radiofrequency main renal artery ablation, 39 to combined radiofrequency ablation of the main artery and branches, and 42 to ultrasound-based treatment. Baseline daytime blood pressure, clinical characteristics, and treatment were well balanced between the groups. At 3 months, systolic daytime ambulatory blood pressure decreased by 9.5±12.3 mm Hg ( P<0.001) in the whole cohort. Although blood pressure was significantly more reduced in the ultrasound ablation group than in the radiofrequency ablation group of the main renal artery (-13.2±13.7 versus -6.5±10.3 mm Hg; mean difference, -6.7 mm Hg; global P=0.038 by ANOVA, adjusted P=0.043), no significant difference was found between the radiofrequency ablation groups (-8.3±11.7 mm Hg for additional side branch ablation; mean difference, -1.8 mm Hg; adjusted P>0.99). Similarly, the blood pressure reduction was not found to be significantly different between the ultrasound and the side branch ablation groups. Frequencies of blood pressure response ≥5 mm Hg were not significantly different (global P=0.77).

CONCLUSIONS

In patients with resistant hypertension, endovascular ultrasound-based RDN was found to be superior to radiofrequency ablation of the main renal arteries only, whereas a combined approach of radiofrequency ablation of the main arteries, accessories, and side branches was not.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT02920034.

Validation of simple measures of aortic distensibility based on standard 4-chamber cine CMR: a new approach for clinical studies

Objective

Aortic distensibility (AD) represents a well-established parameter of aortic stiffness. It remains unclear, however, whether AD can be obtained with high reproducibility in standard 4-chamber cine CMR images of the descending aorta. This study investigated the intra- and inter-observer agreement of AD based on different angles of the aorta and provided a sample size calculation of AD for future trials.

Methods

Thirty-one patients underwent CMR. Angulation of the descending aorta was performed to obtain strictly transversal and orthogonal cross-sectional aortic areas. AD was obtained both area and diameter based.

Results

For area-based values, inter-observer agreement was highest for 4-chamber AD (ICC 0.97; 95% CI 0.93–99), followed by orthogonal AD (ICC 0.96; 95% CI 0.91–98) and transversal AD (ICC 0.93; 95% CI 0.80–97). For diameter-based values, agreement was also highest for 4-chamber AD (ICC 0.97; 95% CI 0.94–99), followed by orthogonal AD (ICC 0.96; 95% CI 0.92–98) and transversal AD (ICC 0.91; 95% CI 0.77–96). Bland–Altman plots confirmed a small variation among observers. Sample size calculation showed a sample size of 12 patients to detect a change in 4-chamber AD of 1 × 10⁻³ mmHg⁻¹ with either the area or diameter approach.

Conclusion

AD measurements are highly reproducible and allow an accurate and rapid assessment of arterial compliance from standard 4-chamber cine CMR.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-019-01525-8) contains supplementary material, which is available to authorized users.

Renal Denervation in Isolated Systolic Hypertension Using Different Catheter Techniques and Technologies

Patients with isolated systolic hypertension (ISH) are thought to show a diminished blood pressure (BP)-lowering effect after renal sympathetic denervation (RDN). This conclusion is mostly derived from unipolar radiofrequency catheter ablation studies. Limited data for newer RDN technologies exist. We used data from the RADIOSOUND-HTN (Three-Arm Randomized Trial of Different Renal Denervation Devices and Techniques in Patients With Resistant Hypertension) comparing 3 different RDN approaches to investigate a possible interaction between ISH and RDN response. One hundred twenty patients were stratified by having ISH or combined systolic-diastolic hypertension (CH). Of these, 39 underwent radiofrequency ablation of the renal main arteries, 39 combined radiofrequency ablation of the main and branch arteries, and 42 were treated with ultrasound-based ablation of the main renal artery. Patients with ISH (n=61) were older and had lower systolic and diastolic BP on ambulatory measurement (ambulatory BP measurement) at baseline in comparison to CH (n=59). At 3 months, patients with ISH showed a less pronounced BP-lowering effect of RDN as compared to patients with CH (daytime average -5.9±11.8 versus -13.3±11.7 mm Hg, P=0.001). This difference was significant for radiofrequency ablation of the renal main arteries and ultrasound-based ablation of the main renal artery treatment but did not reach significance in the radiofrequency ablation of the main and branch arteries group. After adjustment for baseline BP values and age, there was no significant difference in BP reduction between ISH and CH. Using unadjusted BP values, RDN seems to be more effective in CH than in ISH. However, adjusting for baseline BP values revealed similar BP reduction in ISH and CH patients, irrespective of the RDN treatment used. The value of ISH as predictor for successful RDN might have been overestimated in the past. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT02920034.

Lessons Learned from RADIOSOUND-HTN: Different Technologies and Techniques for Catheter-based Renal Denervation and Their Effect on Blood Pressure

The interest in renal denervation (RDN) as a treatment for arterial hypertension has returned with three proof of principle trials that have shown recently RDN to be superior to sham treatment. Nevertheless, many questions about this treatment remain open, including those around the optimal interventional technique and technology. To clarify this important question, the authors designed and conducted the Randomized Trial of Different Renal Denervation Devices and Techniques in Patients with Resistant Hypertension (RADIOSOUND-HTN) trial, which compared three RDN treatment arms in a prospective randomised clinical trial. In this article, they comment on the background and results of this trial, and discuss which conclusions can be drawn from the trial, and which questions remain open for future studies in this field.

Differential effects of inhibition of interleukin 1 and 6 on myocardial, coronary and vascular function

BACKGROUND

Anakinra, an interleukin-1 receptor antagonist and tocilizumab, an interleukin-6 receptor blocker, are used for the treatment of rheumatoid arthritis. We investigated the differential effects of anakinra and tocilizumab on myocardial and vascular function in an atherosclerosis model of patients with rheumatoid arthritis.

METHODS

120 patients with rheumatoid arthritis were randomized to anakinra (n = 40), tocilizumab (n = 40) or prednisolone (n = 40) for 3 months. Primary outcome measure was the change of left ventricular longitudinal strain after 3 months of treatment. Additionally, we measured coronary flow reserve, flow-mediated dilatation of the brachial artery, carotid-femoral pulse wave velocity, malondialdehyde and protein carbonyls as oxidative stress markers and C-reactive protein blood levels at baseline and post-treatment.

RESULTS

At baseline, patients among the three treatment arms had similar age, sex, disease activity score and atherosclerotic risk factors. Compared with baseline, all patients had improved longitudinal strain (- 16% vs. - 17.8%), coronary flow reserve (2.56 vs. 2.9), malondialdehyde (2.0 vs. 1.5 µM/L), protein carbonyls (0.0132 vs. 0.0115 nmol/mg), and C-reactive protein post-treatment. In all patients, the percent decrease of malondialdehyde was correlated with percent increase of longitudinal strain (p < 0.001). Compared with tocilizumab and prednisolone, anakinra treatment resulted in a greater improvement of longitudinal strain (18.7% vs. 9.7% vs. 6%) and coronary flow reserve (29% vs. 13% vs. 1%), while pulse wave velocity and brachial blood pressure were improved only after tocilizumab treatment (11 ± 3 vs. 10.3 ± 2 m/s p < 0.05 for all comparisons).

CONCLUSIONS

Anakinra is associated with an improvement in cardiac function and tocilizumab with improvement in vascular function.

CLINICAL TRIAL REGISTRATION

URL: https:// http://www.clinicaltrials.gov . Unique identifier: NCT03288584.