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
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 84
- 试验地点
- 1
- 主要终点
- Change in brain BOLD signal intensity
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •signed informed consent
- •capable of discernment
排除标准
- •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
结局指标
主要结局
Change in brain BOLD signal intensity
时间窗: 1.5 hours
Changes in the brain BOLD fMRI signal of the brainstem in response to a cold pressor test
次要结局
- Functional connectivity (resting state and effective connectivity)(1.5 hours)
- Structural connectivity(30 minutes)
- Correlation between brain BOLD fMRI and renal ultrasound(2 hours)
研究者
PD Dr. Grégoire Wuerzner
Primary Investigator, MD
Centre Hospitalier Universitaire Vaudois