Targeting Breathing Limitations to Improve Functional Outcomes in Heart Failure With Preserved Ejection Fraction (HFpEF)
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 78
- 试验地点
- 1
- 主要终点
- O2 cost of breathing (Objective 1)
研究概览
简要总结
The overall purpose of this study is to investigate whether pulmonary limitations that increase the oxygen (O2) cost of breathing impact dyspnea on exertion (DOE) and peak exercise capacity in patients with HFpEF and obesity. As per investigator's hypothesis, obesity is likely a significant contributor to DOE and exercise intolerance in patients with HFpEF.
详细描述
Clinical screening tests including cardiopulmonary exercise testing (CPET), pulmonary function testing, and dual-energy x-ray absorptiometry (DEXA) scans will be performed on all subjects. Investigator's approach will be to undertake the following objectives:
Objective 1: (Observational) is a cross-sectional study designed to test the interaction of HFpEF (underlying changes in pulmonary function) and obesity (obesity-related changes in pulmonary function) on the O2 cost of breathing, and its association with DOE and peak exercise capacity. The specific hypotheses proposed to test as part of this objective are:
Hypothesis 1.1: Due to the presence of obesity-related mechanical ventilatory constraints, the O2 cost of breathing will be greater in obese HFpEF patients and obese controls vs. nonobese HFpEF patients and nonobese controls, but will be similar between obese HFpEF patients vs. obese controls.
Hypothesis 1.2: The association between the O2 cost of breathing and DOE and the association between the O2 cost of breathing and peak exercise capacity will be stronger in obese HFpEF patients and obese controls vs. nonobese HFpEF patients and nonobese controls, but will be similar between obese HFpEF patients vs. obese controls.
Objective 2: (Interventional) is a single-blind, randomized, placebo-controlled, cross-over trial designed to investigate the effects of reducing obesity-related mechanical ventilatory constraints by breathing a HeO2 gas mixture (HeO2: 21% O2 and 79% He) on DOE and peak exercise capacity. The specific hypotheses proposed to test as part of this objective are:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Other
- 盲法
- Single (Participant)
盲法说明
The order of the room air and HeO2 tests will be randomized and the subjects will not be told what gas mixture they will be breathing.
入排标准
- 年龄范围
- 55 Years 至 90 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •signs and symptoms of heart failure
- •an ejection fraction > 0.50;
- •objective evidence of diastolic dysfunction. elevated biomarkers (NT-proBNP >300 ng/dl) or HF hospitalization
- •healthy volunteers
排除标准
- •age < 55 years
- •BMI > 50 kg/m2
- •Atrial fibrillation with poorly controlled heart rate
- •phosphodiesterase type 5 (PDE5) inhibitor use
- •severe valvular disease
- •severe Chronic obstructive pulmonary disease (COPD)
- •Chronic kidney disease (CKD) 4 or higher
- •any restriction of ambulation and mobility.
研究组 & 干预措施
HeO2 gas mixture, then Room air gas mixture
Participant will be randomized to each intervention on separate days (Study visit 3 and 4) in this cross-over trial. Participants that receive HeO2 first will then receive the room air gas mixture. At least 24 hours will separate each visit.
干预措施: HeO2 gas mixture (Other)
HeO2 gas mixture, then Room air gas mixture
Participant will be randomized to each intervention on separate days (Study visit 3 and 4) in this cross-over trial. Participants that receive HeO2 first will then receive the room air gas mixture. At least 24 hours will separate each visit.
干预措施: Room air gas mixture (Other)
Room air gas mixture, then HeO2 gas mixture
Participant will be randomized to each intervention on separate days (Study visit 3 and 4) in this cross-over trial. Participants that receive Room air first will then receive the HeO2 mixture. At least 24 hours will separate each visit.
干预措施: HeO2 gas mixture (Other)
Room air gas mixture, then HeO2 gas mixture
Participant will be randomized to each intervention on separate days (Study visit 3 and 4) in this cross-over trial. Participants that receive Room air first will then receive the HeO2 mixture. At least 24 hours will separate each visit.
干预措施: Room air gas mixture (Other)
结局指标
主要结局
O2 cost of breathing (Objective 1)
时间窗: Day 2
O2 cost of breathing measured during eucapnic voluntary hyperventilation, and calculated using oxygen uptake and ventilation variables.
Change in DOE during HeO2 breathing (Objective 2)
时间窗: Day 3 or 4
Dyspnea on Exertion (DOE) will be assessed via ratings of perceived breathlessness (RPB) using a 0-10 Borg Scale, and will be compared with that measured during room air breathing.
Change in peak exercise capacity during HeO2 breathing (Objective 2)
时间窗: Day 3 or 4
Peak exercise capacity will be assessed by measuring peak oxygen uptake (in L/min, measured via a breath-by-breath metabolic measurement system), peak power output recorded from a cycle ergometer (Watts), and/or total exercise duration (minutes).
次要结局
未报告次要终点
研究者
Bryce Balmain
Principal Investigator
University of Texas Southwestern Medical Center