Moore Brian, Brubaker Peter H, Stewart Kathryn P, Kitzman Dalane W
Section on Cardiology, Department of Internal Medicine, Wake Forest University, Winston-Salem, North Carolina, USA.
J Card Fail. 2007 May;13(4):259-62. doi: 10.1016/j.cardfail.2006.12.005.
Oxygen consumption (VO2) has previously been used for prognosis and risk stratification in patients with heart failure. More recent research has introduced VE/VCO2 slope as a prognostic measure. Risk of mortality is thought to increase when VE/VCO2 slope values are greater than 34. Therefore, the purpose of this study was to cross-sectionally examine VE/VCO2 slope in systolic heart failure (SHF) and diastolic heart failure (DHF) as well as age-matched healthy controls.
Maximal graded exercise tests were conducted on 147 patients (59 DHF, 60 SHF, and 28 controls) using a bicycle ergometer. Breath-by-breath expired gas analysis was performed using a commercially available system with on-line computer calculations. VE/VCO2 slope was calculated from a regression line of minute ventilation and carbon dioxide production. One-way analysis of covariance with a Bonferroni post hoc test and Pearson correlations were used for statistical analysis. VE/VCO2 slope was significantly higher in SHF when compared to both DHF (37 +/- 8 vs. 34 +/- 7, P = .03) and controls (37 +/- 8 vs. 32 +/- 5, P = .002). No significant difference was observed between DHF and healthy controls (34 +/- 7 vs. 32 +/- 5, P = .52). Additional analysis resulted in significant correlations between VO2 and VE/VCO2 slope in systolic heart failure patients (r = -0.40, P = .002); however, there was no significant relationships in diastolic heart failure patients (r = -0.09, P = .49) or in controls (r = 0.13, P = .50).
VE/VCO2 slope is significantly higher in patients with SHF compared with DHF and healthy controls.
以往氧耗量(VO2)已用于心力衰竭患者的预后评估和风险分层。最近的研究引入了VE/VCO2斜率作为一种预后指标。当VE/VCO2斜率值大于34时,死亡风险被认为会增加。因此,本研究的目的是横断面研究收缩性心力衰竭(SHF)、舒张性心力衰竭(DHF)以及年龄匹配的健康对照者的VE/VCO2斜率。
对147例患者(59例DHF、60例SHF和28例对照者)使用自行车测力计进行最大分级运动试验。使用市售系统并通过在线计算机计算进行逐次呼吸的呼出气分析。VE/VCO2斜率由分钟通气量和二氧化碳产生量的回归线计算得出。采用协方差分析及Bonferroni事后检验和Pearson相关性分析进行统计学分析。与DHF(37±8 vs. 34±7,P = 0.03)和对照者(37±8 vs. 32±5,P = 0.002)相比,SHF患者的VE/VCO2斜率显著更高。DHF患者与健康对照者之间未观察到显著差异(34±7 vs. 32±5,P = 0.52)。进一步分析发现,收缩性心力衰竭患者的VO2与VE/VCO2斜率之间存在显著相关性(r = -0.40,P = 0.002);然而,舒张性心力衰竭患者(r = -0.09,P = 0.49)或对照者(r = 0.13,P = (此处原文有误,应为0.50))中未发现显著相关性。
与DHF患者和健康对照者相比,SHF患者的VE/VCO2斜率显著更高。