METHODS: A cross sectional study of 70 asymptomatic male CKD patients [CKD stages 2-5 (pre-dialysis)] without primary cardiac disease or diabetes mellitus and 25 HF patients. A specialized CPX with a CO2 rebreathing technique was utilized to measure the peak cardiac output and peak cardiac power output. The peak O2 consumption (VO2peak) and AT were also measured during the test. Parameters such as the O2-pulse, stroke volume, arteriovenous difference in O2 concentration [C(a-v)O2], peak circulatory power, and peak ventilatory power were all calculated. Pearson\'s correlation, univariate, and multivariate analyses were applied.
RESULTS: Whereas there was a strong correlation between the peak O2-pulse and measured peak SV in HF, the correlation was less robust in CKD. Similarly, the correlation between the estimated SV and the measured SV was less robust in CKD compared to HF. The AT only showed a modest correlation with the CPOpeak in HF and only a weak correlation in CKD. A stronger correlation was demonstrated between the peak circulatory power and CPOpeak, and the ventilatory power and CPOpeak. In HF, the central cardiac factor was the predominant determinant of the standard CPX-derived surrogate indices of cardiac performance. By contrast, in CKD both central and peripheral factors played an equally important role, making such indices less reliable markers of cardiac performance per se in CKD.
CONCLUSIONS: The results highlight that the standard CPX-derived surrogate markers of cardiac performance may be less reliable in CKD, and that further prospective studies comparing such surrogate markers with directly measured cardiac hemodynamics are required before adopting such markers into clinical practice or research in CKD.
方法:一项对70例无原发性心脏病或糖尿病的无症状男性CKD患者[CKD2-5期(透析前)]和25例HF患者进行的横断面研究。使用具有CO2再呼吸技术的专用CPX来测量峰值心输出量和峰值心功率输出量。在测试过程中还测量了峰值O2消耗(VO2peak)和AT。O2脉冲等参数,每搏输出量,O2浓度的动静脉差异[C(a-v)O2],峰值循环功率,并计算了峰值通气功率。皮尔森的相关性,单变量,并应用多变量分析。
结果:尽管峰值O2脉冲与HF中测得的峰值SV之间存在很强的相关性,CKD的相关性较不稳健。同样,与HF相比,在CKD中,估计的SV与测量的SV之间的相关性不那么稳健.AT仅显示与HF中的CPO峰的适度相关性,而在CKD中仅显示弱相关性。峰值循环功率和CPOpeak之间具有更强的相关性,以及通气力和CPOpeak。在HF中,中心心脏因素是CPX衍生的标准心脏表现替代指数的主要决定因素.相比之下,在CKD中,中枢和外周因素起着同等重要的作用,使这些指标在CKD中心脏表现本身的可靠性较低。
结论:结果突出表明,标准CPX衍生的心脏表现替代标志物在CKD中可能不太可靠,并且在将此类标记物用于CKD的临床实践或研究之前,需要进一步的前瞻性研究将此类替代标记物与直接测量的心脏血流动力学进行比较。