Sperling Milena Pelosi Rizk, Caruso Flávia Cristina Rossi, Mendes Renata Gonçalves, Dutra Daniela Bassi, Arakelian Vivian Maria, Bonjorno José Carlos, Catai Aparecida Maria, Arena Ross, Borghi-Silva Audrey
Programa de Pós-graduação Interunidades Bioengenharia (EESC/FMRP/IQSC), Universidade de São Paulo, USP, São Carlos, SC, Brasil.
Laboratório de Fisioterapia Cardiopulmonar, Universidade Federal de São Carlos, UFSCar, São Carlos, SP, Brasil.
Clin Physiol Funct Imaging. 2016 Mar;36(2):92-8. doi: 10.1111/cpf.12197. Epub 2014 Oct 13.
Non-invasive assessment of haemodynamic function by impedance cardiography (IC) constitutes an interesting approach to monitor cardiac function in patients with coronary artery disease (CAD). However, such measurements are most often performed at rest, whereas symptoms are also possible during exertion, particularly at higher intensities. In addition, the association between IC during exertion and cardiopulmonary exercise testing (CPX) is not well understood in these patients, which was the aim of this study.
Nineteen men (age = 62 ± 6 years) with CAD [left ventricular ejection fraction (LVEF) = 61 ± 10%] underwent a CPX using an incremental protocol on a cycle ergometer, with simultaneous measurement of IC. Cardiac output (CO), stroke volume (SV), cardiac index (CI), peak oxygen consumption (VO2 ), the oxygen uptake efficiency slope (OUES), circulatory power and ventilatory power were determined.
Pearson product-moment correlation analysis revealed peak VO2 (r = 0·46) was significantly related to CO. Peak oxygen pulse (0·52) was associated with SV. OUES was associated with resting SV (0·47) and with peak SV (r = 0·52).
These findings suggest that IC indices are associated with certain, but not all, established CPX measures in patients with stable CAD.
通过阻抗心动图（IC）对血流动力学功能进行无创评估是监测冠心病（CAD）患者心功能的一种有趣方法。然而，此类测量大多在静息状态下进行，而症状也可能在运动时出现，尤其是在高强度运动时。此外，在这些患者中，运动时的IC与心肺运动试验（CPX）之间的关联尚未得到充分理解，而这正是本研究的目的。
19名患有CAD的男性（年龄 = 62 ± 6岁，左心室射血分数[LVEF] = 61 ± 10%）采用递增方案在自行车测力计上进行CPX，并同时测量IC。测定心输出量（CO）、每搏输出量（SV）、心脏指数（CI）、峰值耗氧量（VO2）、摄氧效率斜率（OUES）、循环功率和通气功率。
Pearson积差相关分析显示，峰值VO2（r = 0·46）与CO显著相关。峰值氧脉搏（0·52）与SV相关。OUES与静息SV（0·47）和峰值SV（r = 0·52）相关。
这些发现表明，在稳定型CAD患者中，IC指标与某些（但并非全部）既定的CPX测量指标相关。
