Ischemic Conditioning to Promote Microvascular Resiliency in Frail Individuals
试验速览
- 阶段
- 2 期
- 状态
- 招募中
- 入组人数
- 60
- 试验地点
- 2
- 主要终点
- Change in Perfused Vessel Density
研究概览
简要总结
The goal of this clinical trial is to see how small blood vessels respond to the stress of high intensity exercise, and if a safe and simple intervention called ischemic conditioning can protect blood vessels from the stress of exercise.
Participants will come in for 3 study visits and get home-based ischemic conditioning. At Study Visit 1, participants will be assessed for their frailty and physical function. Afterwards, they will perform an exercise test. At Study Visit 2, patients will undergo 2 microvascular assessments, perform a high-intensity exercise, then undergo the same 2 microvascular assessments again. Participants will be given a handheld sphygmomanometer and a blood pressure cuff to take home. Depending on which group the participants get randomized into, participants will place the blood pressure cuff around their non-dominant upper arm and inflate to either a low or high pressure for 2 weeks at home. Participants will repeat the same steps in Study Visit 2 for Study Visit 3. In addition, participants will also be assessed for their frailty and physical function.
详细描述
In elderly individuals the small blood vessels that regulate blood flow to organs and other tissues can become damaged when they are exposed to stress, which can lead to complications following stressful events like surgery. In this study we will examine how these blood vessels respond to the stress of high intensity exercise, and if a safe and simple intervention called ischemic conditioning can increase resiliency of these vessels.
Our previous work showed that conditioned athletes are protected from the stress of a single, high intensity exercise bout whereas non-athletes are not. Others have shown that elderly individuals have reduced large artery function following the high intensity exercise. This study will be the first to examine how the small blood vessels respond to this stress in the elderly. Participants will be asked to come in for 3 study visits.
Study Visit 1
- Complete assessments on frailty and physical function
- Complete an exercise test using either a total body recumbent stepper or a bicycle and pedal in a seated position
Study Visit 2
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 65 Years 至 85 Years（Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Women and men ages 65-85 years of age
排除标准
- •Myocardial infarction in last 6 months
- •morbid obesity (BMI >40)
- •heart failure
- •uncontrolled hypertension
- •other condition that precludes high intensity exercise (ex, neurological disorder, acute systemic infection)
- •history of blood clots in the extremities
- •any condition in which compression of the arm or transient ischemia is contraindicated (e.g., wounds in the arm).
结局指标
主要结局
Change in Perfused Vessel Density
时间窗: 0.5 hours
Total vessel density (TVD) will be calculated using the DeBacker Score manual analysis on all images that have a minimum microcirculation image quality score (MIQS) of 10. Perfused vessel density (PVD) will be calculated by multiplying total vessel density (TVD) x proportion of perfused vessels (PPV%).
Change in Acetylcholine-mediated dilation
时间窗: 2 hours
Cutaneous vascular conductance in response to acetylcholine infusion will be calculated as laser Doppler flux / mean arterial pressure
次要结局
未报告次要终点
研究者
Matthew Durand
Associate Professor
Medical College of Wisconsin