Dietary Nitrate Supplementation and Cardiorespiratory Control in Chronic Heart Failure: a Randomized, Placebo-controlled Trial
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 13
- 主要终点
- Exercise tolerance
研究概览
简要总结
The main purpose of this study is to determine whether dietary nitrate supplementation via concentrated beetroot juice improves central and peripheral cardiovascular control and physical capacity in patients with systolic heart failure.
详细描述
Chronic heart failure (CHF) is a leading cause of morbidity and mortality worldwide. Although affecting the heart at first, it is now recognized that disability is largely due to impaired cerebral and skeletal muscle blood flow and consequently microvascular oxygenation. Reduced muscle oxygenation compromises oxidative metabolism and thus contractile performance. Impaired cerebral oxygenation not only reduces motor output (thus exacerbating muscle fatigue) but also constitutes a predictor of cerebral ischemic events and an independent prognostic risk factor.
Reduced levels of the vasodilator nitric oxide (NO) contribute to impaired blood flow and oxygenation in CHF. Development of new effective therapeutic strategies is therefore crucial given that current pharmacological treatment has failed to abrogate oxygenation deficits in CHF patients. Emerging evidence shows that nitrate serves as an alternative source for NO and improves muscle blood flow and oxygenation in health. Another striking feature of nitrate is that it can improve muscle work efficiency, a tenet of physiology that was once considered immutable.
Objective
To investigate systematically the role of dietary nitrate supplementation on central and peripheral cardiovascular function in CHF patients.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 40 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •previous diagnosis of systolic heart failure (left ventricular ejection fraction <40%) under optimized clinical treatment as judged by the accompanying physician.
排除标准
- •hospital admission in the previous 6 weeks;
- •exercise training program in the previous 6 months;
- •nitrate therapy (e.g., isosorbide dinitrate);
- •tabagism;
- •any condition that could interfere with the ability to exercise;
- •diagnosed psychiatric or cognitive disorders;
- •type I insulin-dependent diabetes mellitus;
- •excessively over-weight (BMI>35kg/m²);
- •other diagnosed cardiorespiratory disorders (e.g., chronic obstructive pulmonary disease, peripheral artery disease).
结局指标
主要结局
Exercise tolerance
时间窗: 8 days
Cycle ergometer exercise test to the limit of tolerance
次要结局
- Plasma nitrate and nitrite concentrations(8 days)
- Central and peripheral fatigue(8 days)
- Skeletal muscle and cerebral blood flow and oxygenation(8 days)
- Neuromuscular activity(8 days)
- Dyspnea and leg effort scores(8 days)
- Cognitive performance(8 days)
- Cardiorespiratory responses to exercise(8 days)
研究者
Dr. J. Alberto Neder
Principal Investigator
Queen's University