Cooke G A, Marshall P, al-Timman J K, Wright D J, Riley R, Hainsworth R, Tan L B
Institute for Cardiovascular Research, University of Leeds, UK.
Heart. 1998 Mar;79(3):289-94. doi: 10.1136/hrt.79.3.289.
To investigate whether physiological cardiac reserve can be measured in man without invasive procedures and whether it is a major determinant of exercise capacity.
Development of method of measurement and an observational study.
A regional cardiothoracic centre.
70 subjects with a wide range of cardiac function, from heart failure patients to athletes.
Subjects underwent treadmill, symptom limited cardiopulmonary exercise tests to measure aerobic exercise capacity (represented by VO2max) and cardiac reserve. Cardiac output was measured non-invasively using the CO2 rebreathing technique.
Cardiac power output (CPOmax) at peak exercise was found to be significantly related to aerobic capacity: CPOmax (W) = 0.35 + 1.5 VO2max (1/min), r = 0.87, p < 0.001. It also correlated well with exercise duration (r = 0.62, p < 0.001), suggesting that cardiac reserve is a major determinant of exercise capacity. In the study, cardiac reserve ranged from 0.27 to 5.65 W, indicating a 20-fold difference between the most impaired cardiac function and that of the fittest subject.
A non-invasive method of estimating physiological cardiac reserve was developed. The reserve was found to be a major determinant of exercise capacity in a population of normal subjects and patients with heart disease. This method may thus be used to provide a clearer definition of the extent of cardiac impairment in patients with heart failure.
研究能否在不进行侵入性操作的情况下测量人体的生理性心脏储备，以及它是否是运动能力的主要决定因素。
测量方法的开发及一项观察性研究。
一个地区性心胸中心。
70名心脏功能范围广泛的受试者，从心力衰竭患者到运动员。
受试者进行症状限制性跑步机心肺运动试验，以测量有氧运动能力（用最大摄氧量VO₂max表示）和心脏储备。使用二氧化碳重呼吸技术无创测量心输出量。
发现运动峰值时的心功率输出（CPOmax）与有氧运动能力显著相关：CPOmax（瓦）= 0.35 + 1.5×VO₂max（升/分钟），r = 0.87，p < 0.001。它也与运动持续时间密切相关（r = 0.62，p < 0.001），表明心脏储备是运动能力的主要决定因素。在该研究中，心脏储备范围为0.27至5.65瓦，表明心脏功能受损最严重者与身体状况最佳者之间相差20倍。
开发了一种估计生理性心脏储备的无创方法。发现该储备是正常受试者和心脏病患者群体运动能力的主要决定因素。因此，这种方法可用于更清晰地界定心力衰竭患者心脏损害的程度。
