scholarly journals Non-invasive quantification of anatomical and functional renal artery vessel wall changes in patients with resistant hypertension undergoing renal denervation using MRI

2014 ◽  
Vol 16 (Suppl 1) ◽  
pp. P172
Author(s):  
Adelina Doltra ◽  
Arthur Hartmann ◽  
Bernhard Schnackenburg ◽  
Christopher Schneeweis ◽  
Rolf Gebker ◽  
...  
Keyword(s):  
Renal Artery ◽  
Resistant Hypertension ◽  
Vessel Wall ◽  
Renal Denervation ◽  
Non Invasive

scholarly journals Early Morphologic Alterations in Renal Artery Wall and Renal Nerves in Response to Catheter-Based Renal Denervation Procedure in Sheep: Difference Between Single-Point and Multiple-Point Ablation Catheters

2017 ◽  
pp. 601-614 ◽  
Author(s):  
M. TÁBORSKÝ ◽  
D. RICHTER ◽  
Z. TONAR ◽  
T. KUBÍKOVÁ ◽  
A. HERMAN ◽  
...  
Keyword(s):  
Renal Artery ◽  
Resistant Hypertension ◽  
Renal Denervation ◽  
Single Point ◽  
Renal Tissue ◽  
Renal Nerves ◽  
Multiple Point ◽  
Renal Nerve ◽  
Jude Medical ◽  
Novel Strategy

Renal sympathetic hyperactivity is critically involved in hypertension pathophysiology; renal denervation (RDN) presents a novel strategy for treatment of resistant hypertension cases. This study assessed effects of two RDN systems to detect acute intravascular, vascular and peri-vascular changes in the renal artery, and renal nerve alterations, in the sheep. The procedures using a single-point or multi-point ablation catheters, Symplicity FlexTM, Medtronic versus EnligHTNTM, St. Jude Medical were compared; the intact contralateral kidneys served as controls. Histopathological and immunohistochemical assessments were performed 48 h after RDN procedures; the kidney and suprarenal gland morphology was also evaluated. Special staining methods were applied for histologic analysis, to adequately score the injury of renal artery and adjacent renal nerves. These were more pronounced in the animals treated with the multi-point compared with the single-point catheter. However, neither RDN procedure led to complete renal nerve ablation. Forty-eight hours after the procedure no significant changes in plasma and renal tissue catecholamines were detected. The morphologic changes elicited by application of both RDN systems appeared to be dependent on individual anatomical variability of renal nerves in the sheep. Similar variability in humans may limit the therapeutic effectiveness of RDN procedures used in patients with resistant hypertension.

Abstract 13272: Efficacy and Safety of Non-invasive Renal Denervation Study Using Externally Delivered Focused Ultrasound in Severe Resistant Hypertension

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Roland E Schmieder ◽  
John A Ormiston ◽  
Petr Neuzil ◽  
Zdenek Stárek ◽  
Patrick Kay ◽  
...  
Keyword(s):  
Resistant Hypertension ◽  
Renal Denervation ◽  
Focused Ultrasound ◽  
Surrounding Tissue ◽  
Renal Nerves ◽  
Antihypertensive Medications ◽  
Serious Adverse Events ◽  
Sound System ◽  
Invasive Approach ◽  
Non Invasive

Background: Invasive catheter based techniques for renal denervation have been extensively examined in treating patients with resistant hypertension, with mixed results and some periprocedural complications. New evidence suggested that not all renal nerves are in the range of invasive procedures limited to a distance 4 to 6 mm from the lumen. Aims: To evaluate the safety and efficacy of an entirely non-invasive approach to renal denervation using externally delivered focused ultrasound to the peri-renal artery tissue with real time Doppler-based image guidance. Methods and results: Twenty-seven patients with severe, treatment resistant hypertension, defined as persistent systolic blood pressure (BP) > 160 mmHg despite 3 or more antihypertensive medications, were treated non-invasively with the Kona Medical Surround Sound System™. Focused ultrasound energy was delivered to the renal arteries bilaterally and surrounding tissue using Doppler-based imaging and continuous tracking with automatic correction for kidney motion throughout treatment. Patients received conscious sedation during the treatment period. At this time, all patients have completed 24 weeks and 23 patients 52 weeks of follow up. Post-denervation, the mean changes from baseline BP (175/92 mmHg) were -16.8/-8.6 mmHg at 3 weeks, -23.2/-10.8 mmHg at 6 weeks, -29.7/-13.1 mmHg at 12 weeks, -21.6/-8.7 mmHg at 24 weeks and -25.6/-10.1 mmHg at 52 weeks . No serious device-related events have been reported to date. Forty-one percent of subjects (11/27) reported mild back pain immediately following the denervation treatment. The majority of cases (7/11) completely resolved within three days post treatment without any significant intervention and no case was associated with any motor, sensory deficits. Conclusions: This is the first study in humans using a non-invasive renal denervation system in severe resistant hypertension. Results showed clinically meaningful reductions from baseline in office BP through 52 weeks post-denervation. The procedure was well-tolerated with no serious adverse events. This technology should enable patients to benefit from renal denervation therapy without the invasive risks associated with catheter based techniques.

scholarly journals Distal renal denervation: cardioprotection in patients with resistant hypertension

2020 ◽  
Vol 19 (4) ◽  
pp. 2225
Author(s):  
E. S. Sitkova ◽  
V. F. Mordovin ◽  
S. E. Pekarsky ◽  
T. M. Ripp ◽  
A. Yu. Falkovskaya ◽  
...  
Keyword(s):  
Renal Artery ◽  
Resistant Hypertension ◽  
Renal Denervation ◽  
Myocardial Damage ◽  
Left Ventricular ◽  
Double Blind Study ◽  
Double Blind ◽  
Damage Area ◽  
Main Renal Artery ◽  
Group 2

Aim. To study the effectiveness of using the anatomically optimized distal renal denervation (RDN) in comparison with the standard approach for reducing myocardial damage and left ventricular (LV) hypertrophy in patients with resistant hypertension (HTN).Material and methods. The randomized double-blind study of the efficacy and safety of distal RDN compared to conventional main renal artery intervention (ClinicalTrials.gov NCT02667912) for the treatment of resistant HTN included 26 patients. All patients were divided into two groups: group 1 (n=16) — distal RDN, group 2 (n=10) — conventional RDN. In addition to 24-hour blood pressure (BP) monitoring, initially and 12 months after the intervention, contrast- enhanced cardiac magnetic resonance imaging was performed to determine the left ventricular mass and non-coronary myocardial damage area. All patients signed informed consent. Twenty-four patients completed the present study.Results. After 12 months, the mean 24-hour BP significantly decreased after both distal RDN (from 167,2±28,5/93,2±19,3 to 147,0±13,7/81,5±9,3 mm Hg (p<0,05)) and conventional RDN (from 157,5±22,5/90,6±23,9 to 139,9±17,7/80,0±16,7 (p<0,05)). Also in both cases, a trend to LV mass decrease was revealed: from 252,6±85,2 to 221,0±60,3 gm (p=0,096) after the distal RDN; from 214,3±54,1 to 186,4±48,1 gm (p=0,071) after the conventional RDN. In contrast, the myocardial damage area decreased only after distal RDN (from 2,33±1,33 to 1,35±0,67 cm3 (p=0,02)) and did not change after conventional RDN.Conclusion. In comparison with the conventional main renal artery intervention, distal RDN in patients with resistant HTN has an additional cardioprotective effect — a decrease in LV myocardial damage area.

scholarly journals Technical advance in silico and in vitro development of a new bipolar radiofrequency ablation device for renal denervation

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Noel Pérez ◽  
Karl Muffly ◽  
Stephen E. Saddow
Keyword(s):  
Radiofrequency Ablation ◽  
Renal Artery ◽  
Resistant Hypertension ◽  
In Silico ◽  
Renal Denervation ◽  
Bipolar Electrode ◽  
Ablation Zone ◽  
Catheter Design ◽  
Basket Catheter

Abstract Background Renal denervation with radiofrequency ablation has become an accepted treatment for drug-resistant hypertension. However, there is a continuing need to develop new catheters for high-accuracy, targeted ablation. We therefore developed a radiofrequency bipolar electrode for controlled, targeted ablation through Joule heating induction between 60 and 100 °C. The bipolar design can easily be assembled into a basket catheter for deployment inside the renal artery. Methods Finite element modeling was used to determine the optimum catheter design to deliver a minimum ablation zone of 4 mm (W) × 10 mm (L) × 4 mm (H) within 60 s with a 500 kHz, 60 Vp-p signal, and 3 W maximum. The in silico model was validated with in vitro experiments using a thermochromic phantom tissue prepared with polyacrylamide gel and a thermochromic ink additive that permanently changes from pink to magenta when heated over 60 °C. Results The in vitro ablation zone closely matched the size and shape of the simulated area. The new electrode design directs the current density towards the artery walls and tissue, reducing unwanted blood temperature increases by focusing energy on the ablation zone. In contrast, the basket catheter design does not block renal flow during renal denervation. Conclusions This computational model of radiofrequency ablation can be used to estimate renal artery ablation zones for highly targeted renal denervation in patients with resistant hypertension. Furthermore, this innovative catheter has short ablation times and is one of the lowest power requirements of existing designs to perform the ablation.

scholarly journals Long-Term Results up to 12 Months After Catheter-Based Alcohol-Mediated Renal Denervation for Treatment of Resistant Hypertension

2021 ◽  
Author(s):  
Felix Mahfoud ◽  
Horst Sievert ◽  
Stefan Bertog ◽  
Lucas Lauder ◽  
Sebastian Ewen ◽  
...  
Keyword(s):  
Renal Artery ◽  
Resistant Hypertension ◽  
Renal Denervation ◽  
Multicenter Trial ◽  
Long Term Results ◽  
Open Label ◽  
Antihypertensive Medications ◽  
Unique Identifier ◽  
Spot Urine

Background: Primary results of this prospective, open-label, multicenter trial suggested that alcohol-mediated renal denervation with perivascular injection of dehydrated alcohol using the Peregrine System Infusion Catheter safely reduces blood pressure (BP) in patients with resistant hypertension. To date, maintenance of the BP-lowering effect beyond 6 months using this novel technology has not been reported. This article describes the final, 12-month follow-up data on the safety and efficacy of alcohol-mediated renal denervation in these patients. Methods: Forty-five patients with resistant hypertension on a stable regimen of on average 5.1±1.5 antihypertensive medications underwent successful bilateral renal denervation using the Peregrine Catheter with alcohol as the neurolytic agent (0.6 mL per renal artery). Apart from 2 vascular access pseudoaneurysms (both without sequelae), no major procedural complications occurred. Results: At 12 months post-procedure, mean 24-hour ambulatory systolic and diastolic BP were reduced by 10 mm Hg (95% CI, −16 to −5) and 7 mm Hg (−10 to −3), respectively ( P <0.001). Office systolic/diastolic BP was reduced by 20/10 mm Hg (−27, −13/−14, −6; <0.001). Compared with baseline, the number of antihypertensive medications was reduced in 21% of patients, while it was increased in 19%. From baseline to 12 months, serum creatinine, urea, cystatin C, and spot urine albumin levels remained unchanged. The change in estimated glomerular filtration rates (−3.9±10.3 mL/minute per 1.73 m 2 [95% CI, −7.1 to −0.75]; P =0.02) was within the expected range. There were no cases of renal artery stenosis up to 12-month follow-up. Conclusions: Catheter-based chemical renal denervation with dehydrated alcohol using the Peregrine Catheter seems to safely reduce BP at follow-up of up to 12 months. Further randomized and sham controlled studies are underway to further validate these findings. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02570113.

scholarly journals Renal Denervation Therapy (RDT) in Resistant Hypertension

2012 ◽  
Vol 2 (2) ◽  
pp. 104-112
Author(s):  
Mohammad Gaffar Amin ◽  
Hasna Fahmima Haque
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Renal Artery ◽  
Resistant Hypertension ◽  
Renal Denervation ◽  
Antihypertensive Drugs ◽  
Antihypertensive Agents ◽  
Radiofrequency Energy ◽  
Sympathetic Nervous

Resistant hypertension is defined as blood pressure that remains above therapeutic goal despite the use of three antihypertensive drugs including a diuretic. As much as one third of patients with arterial hypertension are treatmentrefractory as they do not reach sufficient blood pressure control despite combination antihypertensive therapy of significant duration. The hyperactivity of sympathetic nervous system (SNS) in the occurrence of treatment-resistant long standing hypertension has been established both in animal models and in clinical practice. In these patients, the kidneys play a central role as an activator of the sympathetic nervous system. The failure of purely pharmacological approaches to treat resistant hypertension has stimulated interest in invasive device-based treatments based on old concepts. In the absence of orally active antihypertensive agents, patients with severe and complicated hypertension were widely treated by surgical denervation of the kidneys until the 1960s, but this approach was associated with a high incidence of severe adverse events and a high mortality rate. A new catheter system using radiofrequency energy has been developed, allowing an endovascular approach to renal denervation and providing patients, with resistant hypertension, with a new therapeutic option that is minimally invasive and can be performed rapidly under local anaesthesia. With this method the afferent and efferent sympathetic nervous fibers surrounding the renal artery are ablated precisely keeping the renal artery intact. To date, this technique has been evaluated only in open-label trials including small numbers of highly selected resistant hypertensive patients with suitable renal artery anatomy. The available evidence suggests a significant and persistent blood pressure-lowering effect and a very low incidence of short & long term complications with no deleterious effects on renal function. These data, although promising, need confirmation in larger randomized controlled clinical trials with longerterm follow-up.DOI: http://dx.doi.org/10.3329/birdem.v2i2.12325(Birdem Med J 2012; 2(2): 104-112)

scholarly journals TCT-87 Non-invasive Renal Denervation Study Using Externally Delivered Focused Ultrasound in Severe Resistant Hypertension: 1 Year Follow up Results

2015 ◽  
Vol 66 (15) ◽  
pp. B40 ◽  
Author(s):  
Roland E. Schmieder ◽  
John A. Ormiston ◽  
Petr Neuzil ◽  
Zdenek Starek ◽  
Patrick Kay ◽  
...  
Keyword(s):  
Resistant Hypertension ◽  
Renal Denervation ◽  
Focused Ultrasound ◽  
Non Invasive
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