The Long-term Safety and Effect of Renal Denervation (RDN flow)

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

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.

Study Overview

• Status: Terminated
• Conditions: Hypertension
• Intervention / Treatment: Device: Renal denervation

Detailed Description

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.

• Study Type: Observational
• Enrollment (Actual): 9

Contacts and Locations

Study Locations

• United Kingdom
  • Middlesex
    • London, Middlesex, United Kingdom, W12 0HS
      • Hammersmith Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

People with resistant hypertension and no contraindication to renal denervation.

Description

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

Study Plan

How is the study designed?

What is the study measuring?

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

Collaborators and Investigators

• Sponsor: Imperial College Healthcare NHS Trust
• Collaborators: Philips Healthcare
• Investigators: Principal Investigator: Sayan Sen, PhD, Consultant Cardiologist

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2021
• Primary Completion (Actual): April 16, 2024
• Study Completion (Actual): April 16, 2024

Study Registration Dates

• First Submitted: March 22, 2023
• First Submitted That Met QC Criteria: April 5, 2023
• First Posted (Actual): April 19, 2023

Study Record Updates

• Last Update Posted (Actual): March 27, 2026
• Last Update Submitted That Met QC Criteria: March 24, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Hypertension; Renal denervation
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypertension
• Other Study ID Numbers: 14/LO/0026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No