Arterial Stiffness as a Predictor of Response to Renal Sympathetic Denervation

Study Overview
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Brief Summary
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This trial is designed to establish invasive and non-invasive measures of arterial stiffness as potential predictors of treatment response to renal sympathetic denervation

Detailed Description
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Regardless of the ongoing debate on the general effect of renal sympathetic denervation in therapy resistant hypertension, all trials published so far face the problem of a certain proportion of nonresponders to treatment. Previous data shows, that to some extent this might be attributable to arterial stiffening. Elevated invasive pulse wave velocity as an established marker for arterial stiffness has been found to be associated with nonresponse to renal denervation treatment in a smaller trial population. This trial attempts to assess the predictive value of different invasive and non-invasive markers for arterial stiffness in an adequately powered population.

Official Title
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Evaluation of Arterial Stiffness as a Predictor of Response to Renal Sympathetic Denervation

Conditions
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Therapy Resistant Arterial Hypertension

Intervention / Treatment
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* Device: Renal sympathetic denervation (RDN)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with therapy resistant arterial hypertension (>=3 antihypertensive drugs including at least one diuretic without any dosage change in the preceding 4 weeks) and office BP >160 mmHg systolic or 90 mmHg diastolic Exclusion Criteria: average systolic daytime BP <135 mmHg in 24h ambulatory blood pressure measurement (ABPM) pregnancy known renal artery stenosis >= 1 renal artery diameter < 4 mm life expectancy <6 months participation in any other clinical trial

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Renal Denervation<br>Renal denervation for therapy resistant arterial hypertension | Device: Renal sympathetic denervation (RDN)<br>* Catheter based renal sympathetic denervation for therapy resistant arterial hypertension<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Predictive value of invasive Pulse wave velocity for blood pressure response after renal denervation | difference in daytime blood pressure (ABPM) between patients with low (<14.4 m/s) vs. high invasive pulse wave velocity | 3 Months | 
| Predictive value of noninvasive and invasive measures of arterial stiffness (Pulse wave velocity assessed invasively, with a piezoelectric device and MRI-based) in combination with clinical variables | AUC of ROCs for noninvasive and invasive measures of arterial stiffness in predicting blood pressure response to renal denervation | 3 Months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in 24h ambulatory blood pressure |  | 3 months, 6 months, 12 months | 
| Change in exercise blood pressure |  | 3 months | 
| Predictive value of MRI-assessed aortic distensibility on Change in daytime ambulatory blood pressure |  | 3 months, 6 months, 12 months | 
| Predictive value of MRI-assessed aortic distensibility on Change in 24 h ambulatory blood pressure |  | 3 months, 6 months, 12 months | 
| Predictive value of MRI-assessed total arterial compliance on Change in daytime ambulatory blood pressure |  | 3 months, 6 months, 12 months | 
| Predictive value of MRI-assessed total arterial compliance on Change in 24 h ambulatory blood pressure |  | 3 months, 6 months, 12 months | 
| comparison of predictive value of invasive pulse wave velocity, invasive central pulse pressure, noninvasive pulse wave velocity, noninvasive central pulse pressure, aortic distensibility, total arterial compliance for Change in ambulatory blood pressure |  | 3 months, 6 months, 12 months |