Cost Effectiveness of Endovascular Ultrasound Renal Denervation in Patients with Resistant Hypertension.

BACKGROUND: Resistant hypertension (rHTN) is defined as blood pressure (BP) of ≥ 140/90 mmHg despite treatment with at least three antihypertensive medications, including a diuretic. Endovascular ultrasound renal denervation (uRDN) aims to control BP alongside conventional BP treatment with antihypertensive medication. This analysis assesses the cost effectiveness of the addition of the Paradise uRDN System compared with standard of care alone in patients with rHTN from the perspective of the United Kingdom (UK) health care system. METHODS: Using RADIANCE-HTN TRIO trial data, we developed a state-transition model. Baseline risk was calculated using Framingham and Prospective Cardiovascular Münster (PROCAM) risk equations to estimate the long-term cardiovascular risks in patients treated with the Paradise uRDN System, based on the observed systolic BP (SBP) reduction following uRDN. Relative risks sourced from a meta-analysis of randomised controlled trials were then used to project cardiovascular events in patients with baseline SBP ('control' patients); utility and mortality inputs and costs were derived from UK data. Costs and outcomes were discounted at 3.5% per annum. Modelled outcomes were validated against trial meta-analyses and the QRISK3 algorithm and real-world evidence of RDN effectiveness. One-way and probabilistic sensitivity analyses were conducted to assess the uncertainty surrounding the model inputs and sensitivity of the model results to changes in parameter inputs. Results were reported as incremental cost-effectiveness ratios (ICERs). RESULTS: A mean reduction in office SBP of 8.5 mmHg with uRDN resulted in an average improvement in both absolute life-years (LYs) and quality-adjusted life-years (QALYs) gained compared with standard of care alone (0.73 LYs and 0.67 QALYs). The overall base-case ICER with uRDN was estimated at £5600 (€6500) per QALY gained (95% confidence interval £5463-£5739 [€6341-€6661]); modelling demonstrated > 99% probability that the ICER is below the £20,000-£30,000 (€23,214-€34,821) per QALYs gained willingness-to-pay threshold in the UK. Results were consistent across sensitivity analyses and validation checks. CONCLUSIONS: Endovascular ultrasound RDN with the Paradise system offers patients with rHTN, clinicians, and healthcare systems a cost-effective treatment option alongside antihypertensive medication.

Patient-Level Pooled Analysis of Ultrasound Renal Denervation in the Sham-Controlled RADIANCE II, RADIANCE-HTN SOLO, and RADIANCE-HTN TRIO Trials.

Importance: Ultrasound renal denervation (uRDN) was shown to lower blood pressure (BP) in patients with uncontrolled hypertension (HTN). Establishing the magnitude and consistency of the uRDN effect across the HTN spectrum is clinically important. Objective: To characterize the effectiveness and safety of uRDN vs a sham procedure from individual patient-level pooled data across uRDN trials including either patients with mild to moderate HTN on a background of no medications or with HTN resistant to standardized triple-combination therapy. Data Sources: A Study of the ReCor Medical Paradise System in Clinical Hypertension (RADIANCE-HTN SOLO and TRIO) and A Study of the ReCor Medical Paradise System in Stage II Hypertension (RADIANCE II) trials. Study Selection: Trials with similar designs, standardized operational implementation (medication standardization and blinding of both patients and physicians to treatment assignment), and follow-up. Data Extraction and Synthesis: Pooled analysis using individual patient-level data using linear regression models to compare uRDN with sham across the trials. Main Outcomes and Measures: The primary outcome was baseline-adjusted change in 2-month daytime ambulatory systolic BP (dASBP) between groups. Results: A total of 506 patients were randomized in the 3 studies (uRDN, 293; sham, 213; mean [SD] age, 54.1 [9.3]; 354 male [70.0%]). After a 1-month medication stabilization period, dASBP was similar between the groups (mean [SD], uRDN, 150.3 [9.2] mm Hg; sham, 150.8 [10.5] mm Hg). At 2 months, dASBP decreased by 8.5 mm Hg to mean (SD) 141.8 (13.8) mm Hg among patients treated with uRDN and by 2.9 mm Hg to 147.9 (14.6) mm Hg among patients treated with a sham procedure (mean difference, -5.9; 95% CI, -8.1 to -3.8 mm Hg; P < .001 in favor of uRDN). BP decreases from baseline with uRDN vs sham were consistent across trials and across BP parameters (office SBP: -10.4 mm Hg vs -3.4 mm Hg; mean difference, -6.4 mm Hg; 95% CI, -9.1 to -3.6 mm Hg; home SBP: -8.4 mm Hg vs -1.4 mm Hg; mean difference, -6.8 mm Hg; 95% CI, -8.7 to -4.9 mm Hg, respectively). The BP reductions with uRDN vs sham were consistent across prespecified subgroups. Independent predictors of a larger BP response to uRDN were higher baseline BP and heart rate and the presence of orthostatic hypertension. No differences in early safety end points were observed between groups. Conclusions and Relevance: Results of this patient-level pooled analysis suggest that BP reductions with uRDN were consistent across HTN severity in sham-controlled trials designed with a 2-month primary end point to standardize medications across randomized groups. Trial Registration: ClinicalTrials.gov Identifier: NCT02649426 and NCT03614260.

Predictors of blood pressure response to ultrasound renal denervation in the RADIANCE-HTN SOLO study.

The blood pressure (BP) lowering response to renal denervation (RDN) remains variable with about one-third of patients not responding to ultrasound or radiofrequency RDN. Identification of predictors of the BP response to RDN is needed to optimize patient selection for this therapy. This is a post-hoc analysis of the RADIANCE-HTN SOLO study. BP response to RDN was measured by the change in daytime ambulatory systolic blood pressure (dASBP) at 2 months post procedure. Univariate regression was used initially to assess potential predictors of outcome followed by multivariate regression analysis. In the univariate analysis, predictors of response to RDN were higher baseline daytime ambulatory diastolic blood pressure (dADBP), the use of antihypertensive medications at screening, and presence of orthostatic hypertension (OHTN) whilst the presence of untreated accessory arteries was a negative predictor of response. Multivariate analysis determined that dADBP and use of antihypertensive medications were predictors of response to RDN with a trend for OHTN to predict response. Obese females also appeared to be better responders to RDN in an interaction model. RDN is more effective in patients with elevated baseline dADBP and those with OHTN, suggesting increased peripheral vascular resistance secondary to heightened sympathetic tone. These assessments are easy to perform in clinical setting and may help in phenotyping patients who will respond better to RDN.

Ultrasound renal denervation for hypertension resistant to a triple medication pill (RADIANCE-HTN TRIO): a randomised, multicentre, single-blind, sham-controlled trial.

BACKGROUND: Endovascular renal denervation reduces blood pressure in patients with mild-to-moderate hypertension, but its efficacy in patients with true resistant hypertension has not been shown. We aimed to assess the efficacy and safety of endovascular ultrasound renal denervation in patients with hypertension resistant to three or more antihypertensive medications. METHODS: In a randomised, international, multicentre, single-blind, sham-controlled trial done at 28 tertiary centres in the USA and 25 in Europe, we included patients aged 18-75 years with office blood pressure of at least 140/90 mm Hg despite three or more antihypertensive medications including a diuretic. Eligible patients were switched to a once daily, fixed-dose, single-pill combination of a calcium channel blocker, an angiotensin receptor blocker, and a thiazide diuretic. After 4 weeks of standardised therapy, patients with daytime ambulatory blood pressure of at least 135/85 mm Hg were randomly assigned (1:1) by computer (stratified by centres) to ultrasound renal denervation or a sham procedure. Patients and outcome assessors were masked to randomisation. Addition of antihypertensive medications was allowed if specified blood pressure thresholds were exceeded. The primary endpoint was the change in daytime ambulatory systolic blood pressure at 2 months in the intention-to-treat population. Safety was also assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT02649426. FINDINGS: Between March 11, 2016, and March 13, 2020, 989 participants were enrolled and 136 were randomly assigned to renal denervation (n=69) or a sham procedure (n=67). Full adherence to the combination medications at 2 months among patients with urine samples was similar in both groups (42 [82%] of 51 in the renal denervation group vs 47 [82%] of 57 in the sham procedure group; p=0·99). Renal denervation reduced daytime ambulatory systolic blood pressure more than the sham procedure (-8·0 mm Hg [IQR -16·4 to 0·0] vs -3·0 mm Hg [-10·3 to 1·8]; median between-group difference -4·5 mm Hg [95% CI -8·5 to -0·3]; adjusted p=0·022); the median between-group difference was -5·8 mm Hg (95% CI -9·7 to -1·6; adjusted p=0·0051) among patients with complete ambulatory blood pressure data. There were no differences in safety outcomes between the two groups. INTERPRETATION: Compared with a sham procedure, ultrasound renal denervation reduced blood pressure at 2 months in patients with hypertension resistant to a standardised triple combination pill. If the blood pressure lowering effect and safety of renal denervation are maintained in the long term, renal denervation might be an alternative to the addition of further antihypertensive medications in patients with resistant hypertension. FUNDING: ReCor Medical.

Comprehensive Assessment of Human Accessory Renal Artery Periarterial Renal Sympathetic Nerve Distribution.

OBJECTIVES: The aim of this study was to understand the anatomy of periarterial nerve distribution in human accessory renal arteries (ARAs). BACKGROUND: Renal denervation is a promising technique for blood pressure control. Despite the high prevalence of ARAs, the anatomic distribution of periarterial nerves around ARAs remains unknown. METHODS: Kidneys with surrounding tissues were collected from human autopsy subjects, and histological evaluation was performed using morphometric software. An ARA was defined as an artery arising from the aorta above or below the dominant renal artery (DRA) or an artery that bifurcated within 20 mm of the takeoff of the DRA from the aorta. The DRA was defined as an artery that perfused >50% of the kidney. RESULTS: A total of 7,287 nerves from 14 ARAs and 9 DRAs were evaluated. The number of nerves was smaller in the ARA than DRA (median: 30 [interquartile range: 17.5 to 48.5] vs. 49 [interquartile range: 36 to 76]; p < 0.0001). In both ARAs and DRAs, the distance from the arterial lumen to nerve was shortest in the distal, followed by the middle and proximal segments. On the basis of the post-mortem angiography, ARAs were divided into large (≥3 mm diameter) and small (<3 mm) groups. The number of nerves was greatest in the DRA, followed by the large and small ARA groups (53 [41 to 97], 38 [25 to 53], and 24.5 [10.5 to 36.3], respectively; p = 0.001). CONCLUSIONS: ARAs showed a smaller number of nerves than DRAs, but these results were dependent on the size of the ARA. Ablation, especially in large ARAs, may allow more complete denervation with the potential to further reduce blood pressure.

12-Month Results From the Unblinded Phase of the RADIANCE-HTN SOLO Trial of Ultrasound Renal Denervation.

OBJECTIVES: This study reports the 12-month results of the RADIANCE-HTN (A Study of the ReCor Medical Paradise System in Clinical Hypertension) SOLO trial following unblinding of patients at 6 months. BACKGROUND: The blood pressure (BP)-lowering efficacy and safety of endovascular ultrasound renal denervation (RDN) in the absence (2 months) and presence (6 months) of antihypertensive medications were previously reported. METHODS: Patients with daytime ambulatory BP ≥135/85 mm Hg after 4 weeks off medication were randomized to RDN (n = 74) or sham (n = 72) and maintained off medication for 2 months. A standardized medication escalation protocol was instituted between 2 and 5 months (blinded phase). Between 6 and 12 months (unblinded phase), patients received antihypertensive medications at physicians' discretion. Outcomes at 12 months included medication burden, change in daytime ambulatory systolic BP (dASBP) and office or home systolic BP (SBP), visit-to-visit variability in SBP, and safety. RESULTS: Sixty-five of 74 RDN patients and 67 of 72 sham patients had 12-month dASBP measurements. The proportion of patients on ≥2 medications (27.7% vs. 44.8%; p = 0.041), the number of medications (0 vs. 1.4; p = 0.015), and defined daily dose (1.4 vs. 2.2; p = 0.007) were less with RDN versus sham. The decrease in dASBP from baseline in the RDN group (-16.5 ± 12.9 mm Hg) remained stable at 12 months. The RDN versus sham adjusted difference at 12 months was -2.3 mm Hg (95% confidence interval [CI]: -5.9 to 1.3 mm Hg; p = 0.201) for dASBP, -6.3 mm Hg (95% CI: -11.1 to -1.5 mm Hg; p = 0.010) for office SBP, and -3.4 mm Hg (95% CI: -6.9 to 0.1 mm Hg; p = 0.062) for home SBP. Visit-to-visit variability in SBP was smaller in the RDN group. No renal artery injury was detected on computed tomographic or magnetic resonance angiography. CONCLUSIONS: Despite unblinding, the BP-lowering effect of RDN was maintained at 12 months with fewer prescribed medications compared with sham.

Six-Month Results of Treatment-Blinded Medication Titration for Hypertension Control After Randomization to Endovascular Ultrasound Renal Denervation or a Sham Procedure in the RADIANCE-HTN SOLO Trial.

BACKGROUND: The multicenter, international, randomized, blinded, sham-controlled RADIANCE-HTN SOLO trial (A Study of the ReCor Medical Paradise System in Clinical Hypertension) demonstrated a 6.3 mm Hg greater reduction in daytime ambulatory systolic blood pressure (BP) at 2 months by endovascular ultrasound renal denervation (RDN) compared with a sham procedure among patients not treated with antihypertensive medications. We report 6-month results after the addition of a recommended standardized stepped-care antihypertensive treatment to the randomized endovascular procedure under continued blinding to initial treatment. METHODS: Patients with a daytime ambulatory BP ≥135/85 mm Hg and <170/105 mm Hg after a 4-week discontinuation of up to 2 antihypertensive medications, and a suitable renal artery anatomy, were randomized to RDN (n=74) or sham (n=72). Patients were to remain off antihypertensive medications throughout the first 2 months of follow-up unless safety BP criteria were exceeded. Between 2 and 5 months, if monthly measured home BP was ≥135/85 mm Hg, a standardized stepped-care antihypertensive treatment was recommended consisting of the sequential addition of amlodipine (5 mg/d), a standard dose of an angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, and hydrochlorothiazide (12.5 mg/d), followed by the sequential uptitration of hydrochlorothiazide (25 mg/d) and amlodipine (10 mg/d). Outcomes included the 6-month (1) change in daytime ambulatory systolic BP adjusted for medications and baseline systolic BP, (2) medication burden, and (3) safety. RESULTS: A total of 69/74 RDN patients and 71/72 sham patients completed the 6-month ambulatory BP measurement. At 6 months, 65.2% of patients in the RDN group were treated with the standardized stepped-care antihypertensive treatment versus 84.5% in the sham group (P=0.008), and the average number of antihypertensive medications and defined daily dose were less in the RDN group than in the sham group (0.9±0.9 versus 1.3±0.9, P=0.010 and 1.4±1.5 versus 2.0±1.8, P=0.018; respectively). Despite less intensive standardized stepped-care antihypertensive treatment, RDN reduced daytime ambulatory systolic BP to a greater extent than sham (-18.1±12.2 versus -15.6±13.2 mm Hg, respectively; difference adjusted for baseline BP and number of medications: -4.3 mm Hg, 95% confidence interval, -7.9 to -0.6, P=0.024). There were no major adverse events in either group through 6 months. CONCLUSIONS: The BP-lowering effect of endovascular ultrasound RDN was maintained at 6 months with less prescribed antihypertensive medications compared with a sham control. CLINICAL TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov. Unique identifier: NCT02649426.

Catheter-based renal sympathetic denervation: chronic preclinical evidence for renal artery safety.

BACKGROUND: Renal sympathetic hyperactivity is associated with hypertension, a leading cause of mortality worldwide. Renal sympathetic denervation via the Symplicity Catheter System has been shown to decrease blood pressure by 33/11 mmHg by 6 months, with no radiofrequency (RF)-related adverse sequelae visible by CT/MR angiography or renal duplex ultrasound 6 months after the procedure. Here, we present preclinical work predating those clinical results. We performed therapeutic renal sympathetic denervation in a swine animal model to characterize the vascular safety and healing response 6 months after renal denervation therapy. METHODS: In December 2007, seven domestic swine received a total of 32 radiofrequency ablations via the Symplicity Catheter System and were euthanatized 6 months later. Renal angiography was done before, immediately after, and 6 months after procedure. The renal vessels were examined histologically with H&E and Movat pentachrome stains to identify evidence of vascular and neural injury. The kidneys and urinary system were also examined for evidence of gross and microscopic abnormalities. RESULTS: Renal nerve injury involved primarily nerve fibrosis, replacement of nerve fascicles with fibrous connective tissue, and thickening of the epineurium and perineurium. Renal arterial findings included fibrosis of 10-25% of the total media and underlying adventitia, with mild disruption of the external elastic lamina. No significant smooth muscle hyperplasia or inflammatory components were observed. There was no renal arterial stenosis or thrombosis observed by angiography or histology. No gross or microscopic device-related abnormalities were noted in the kidney, surrounding stroma, or urinary bladder. CONCLUSIONS: In a swine model, renal denervation via the Symplicity Catheter System resulted in no clinically significant adverse renal artery or renal findings 6 months after the procedure. This is corroborated by the vascular safety profile demonstrated in subsequent human clinical studies.