Brain BOLD fMRI in Hypertensive and Normotensive Participants

Hypertension,Essential Clinical Trial

— BRAIrdN  

Official title:

Central Blood Pressure Regulation by the Brainstem and Influence by Renal Sympathetic Afference: a Functional Magnetic Resonance Imaging (MRI) Study in Hypertensive and Normotensive Participants

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03473275
• Other study ID #: 2018-00105
• Status: Completed
• Start date: August 16, 2018
• Est. completion date: August 12, 2022

Study information

• Verified date: February 2023
• Source: Centre Hospitalier Universitaire Vaudois
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

This study will explore the brainstem activity in response to stress in hypertensive patients and normotensive subjects. In addition, it will evaluate if the response in hypertensive patients can be modulated by blocking the afferent signalling of sympathetic nervous system from the kidney to the brain achieved by renal denervation.

The investigators hypothesize that the change in BOLD signal intensity in response to stress is higher in hypertensive patients than in normotensive subjects and that in patients responsive to renal denervation the change in BOLD signal intensity in response to stress is decreased compared to non-responders or to non-denervated resistant hypertensive patients.

Description:

In hypertension, the overactivity of the sympathetic nervous system (SNS) has been found to be implicated in its initiation, maintenance and adverse consequences. The SNS is composed of an afferent and efferent arm, which brings sensory information to the brain (e.g. brainstem and hypothalamus) and transmits sympathetic outflow from the brain to the peripheral organs, respectively. Selective removal of the afferent renal component of the SNS can modulate central sympathetic outflow to the kidney, heart and vasculature in animals. The specific contribution of afferent nerve signalling in hypertension and in the potential antihypertensive effect of renal denervation has not been studied in humans.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 84
• Est. completion date: August 12, 2022
• Est. primary completion date: August 12, 2022
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• signed informed consent

• capable of discernment

Exclusion Criteria:

• having contra-indications for MRI (claustrophobia, cardiac pacemaker or other metallic or mechanical implant or device, etc.)

• pregnant women

• lower limb sensitive neuropathy

• Blood pressure >180/110 mmHg during washout period (for hypertensive patients)

• Intolerance to Sonovue®(ultrasound contrast agent)

• Acute or chronic disease other than hypertension that influences renal function

• taking medication/drugs, except of calcium channel blockers for resistant hypertensive patients

Related Conditions & MeSH terms

• Essential Hypertension
• Hypertension
• Hypertension,Essential

Intervention

Diagnostic Test:
• Cold Pressor test
Both feet in icy waterbath alternated with body temperature water
• PinPrick test
Pricking both feet with a needle using gravity (without penetrating) alternated with cotton swap

Locations

Country	Name	City	State
Switzerland	CHUV, nephrology service	Lausanne	Vaud

Sponsors (2)

Lead Sponsor	Collaborator
Centre Hospitalier Universitaire Vaudois	Ecole Polytechnique Fédérale de Lausanne

Country where clinical trial is conducted

Switzerland, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in brain BOLD signal intensity	Changes in the brain BOLD fMRI signal of the brainstem in response to a cold pressor test	1.5 hours
Secondary	Functional connectivity (resting state and effective connectivity)	Activation patterns in spatially separated brain regions tending to have synchronous activity in resting state and activation pattern changes during a cold pressor test	1.5 hours
Secondary	Structural connectivity	Map of anatomical (neural) connections within the brain in normotensive subjects and hypertensive patients	30 minutes
Secondary	Correlation between brain BOLD fMRI and renal ultrasound	Correlation between changes in brain BOLD signal and renal (contrast-enhanced) ultrasound endpoints	2 hours