Helios Clinics Wuppertal - Department of Cardiology, University Hospital Witten/Herdecke, Wuppertal - Germany.
University Wuppertal - Department of Movement and Training Science, Wuppertal - Germany.
Arq Bras Cardiol. 2019 Jul 10;113(2):231-239. doi: 10.5935/abc.20190116.
Thoracic bioreactance (TB), a noninvasive method for the measurement of cardiac output (CO), shows good test-retest reliability in healthy adults examined under research and resting conditions.
In this study, we evaluate the test-retest reliability of CO and cardiac power (CPO) output assessment during exercise assessed by TB in healthy adults under routine clinical conditions.
25 test persons performed a symptom-limited graded cycling test in an outpatient office on two different days separated by one week. Cardiorespiratory (power output, VO2peak) and hemodynamic parameters (heart rate, stroke volume, CO, mean arterial pressure, CPO) were measured at rest and continuously under exercise using a spiroergometric system and bioreactance cardiograph (NICOM, Cheetah Medical).
After 8 participants were excluded due to measurement errors (outliers), there was no systematic bias in all parameters under all conditions (effect size: 0.2-0.6). We found that all noninvasively measured CO showed acceptable test-retest-reliability (intraclass correlation coefficient: 0.59-0.98; typical error: 0.3-1.8). Moreover, peak CPO showed better reliability (intraclass correlation coefficient: 0.80-0.85; effect size: 0.9-1.1) then the TB CO, thanks only to the superior reliability of MAP (intraclass correlation coefficient: 0.59-0.98; effect size: 0.3-1.8).
Our findings preclude the clinical use of TB in healthy subject population when outliers are not identified.
胸腔生物电阻抗（TB）是一种非侵入性的测量心输出量（CO）的方法，在研究和休息条件下，对健康成年人进行检查时，具有良好的测试-重测可靠性。
本研究评估了 TB 在健康成年人常规临床条件下运动时评估 CO 和心脏功率（CPO）输出的测试-重测可靠性。
25 名测试人员在两个不同的日子里，在一周的间隔时间内，在门诊办公室进行了一项症状限制的分级踏车试验。心肺（功率输出，峰值 VO2）和血液动力学参数（心率、每搏量、CO、平均动脉压、CPO）在休息和运动时使用呼吸功测量系统和生物电阻抗心图（NICOM，Cheetah Medical）连续测量。
在排除 8 名因测量误差（离群值）而导致的参与者后，所有参数在所有条件下均无系统偏差（效应量：0.2-0.6）。我们发现所有非侵入性测量的 CO 均具有可接受的测试-重测可靠性（组内相关系数：0.59-0.98；典型误差：0.3-1.8）。此外，由于 MAP 的可靠性更高（组内相关系数：0.59-0.98；效应量：0.3-1.8），峰值 CPO 的可靠性优于 TB CO（组内相关系数：0.80-0.85；效应量：0.9-1.1）。
当未识别出离群值时，我们的发现排除了 TB 在健康受试者人群中的临床应用。
