The Long-term Safety and Effect of Renal Denervation

Study Overview
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Brief Summary
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The goal of this observational study is to learn about the effects of renal denervation in patients with resistant hypertension. The main question it aims to answer is: What are the long term effects of renal denervation on blood pressure and flow within the arteries? Participants will undergo an assessment of their blood pressure, echocardiogram and invasive measurements of blood pressure and flow in the aorta and renal arteries before undergoing the renal denervation procedure. 6 months later these assessments will be repeated.

Detailed Description
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Renal denervation is emerging as a succesful technique in the treatment of high blood pressure particularly for those people who's disease is resistant to drug therapy. It involves insertion of an catheter through the femoral artery and into the renal artery where it delivers a controlled radiofrequency ablation to the renal artery wall. The purpose of this ablation is to interupt the sympathetic nervous system which is inappropriately activated in hypertension. Its beneficial effects on BP reduction has been borne out in a recently published randomised clinical trial which demonstrated a reduction in blood pressure in patients who underwent denervation compared to those managed with medication alone and it is now being used worldwide to manage hypertensive patients. The safety of this procedure has been demonstrated in the peri-operative setting and short term particularly regarding anatomical changes and kidney function. However, its effects have not been demonstrated with invasive imaging or physiological testing in the long term. Therefore, the investigators recognise that a repeat assessment 6 months after denervation using invasive measures (to perform detailed assessments of the effects on aortic, flow and artery stiffness) would be of great benefit in stratifying this technique, which is likely to become widespread in the very near future. The investigators therefore plan to perform denervation in 20 patients and obtain detailed information on kidney and aortic blood pressure and flow. They will then reassess these parameters after 6 months in the same patients to ensure preservation of pressure, flow and energy transfer and document the effects of denervation on vascular stiffness.

Official Title
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The Long-term Safety and Effect of Renal Denervation for Resistant Hypertension

Conditions
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Hypertension

Intervention / Treatment
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* Device: Renal denervation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Systolic blood pressure >160mmHg despite 3 antihypertensive agents eGFR >45 Exclusion Criteria: Secondary causes of hypertension Prior renal artery intervention Renal insufficiency Significant stenotic valvular heart disease Myocardial infarction, unstable angina or stroke within the preceding 6 months

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Renal denervation|Renal denervation (ReCor Medical)|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in systolic blood pressure | Invasively measured aortic systolic pressure | At baseline and at 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in diastolic pressure | Invasively measured aortic diastolic pressure | At baseline and 6 months | 
| Change in renal artery pressure | Invasively measured | At baseline and 6 months | 
| Change in renal artery flow | Invasively measured | At baseline and 6 months | 
| Change in renal artery resistance | Invasively measured | At baseline and 6 months | 
| Change in aortic reservoir pressure | Invasively measured | At baseline and 6 months | 
| Change in aortic wavespeed | Invasively measured | At baseline and 6 months | 
| Change in aortic reservoir wave intensity | Invasively measured | At baseline and 6 months | 
| Change in left ventricular wall thickness | Assessed during echocardiography | At baseline and 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypertension, Renal denervation