Francis D P, Shamim W, Davies L C, Piepoli M F, Ponikowski P, Anker S D, Coats A J
National Heart & Lung Institute, Imperial College of Science, Technology and Medicine, London, U.K.
Eur Heart J. 2000 Jan;21(2):154-61. doi: 10.1053/euhj.1999.1863.
Chronic heart failure carries a poor prognosis. Cardiopulmonary exercise testing is useful in predicting survival. We set out to establish the prognostic value of peak VO(2)and VE/VCO(2)slope across a range of threshold values.
Three hundred and three consecutive patients with stable chronic heart failure underwent cardiopulmonary exercise testing between 1992 and 1996. Their age was 59+/-11 years (mean+/-SD), peak VO(2)17. 8+/- 6.6 ml. kg(-1)min(-1), VE/VCO(2)slope 37+/-12. At the end of follow-up in January 1999, 91 patients had died (after a median of 7 months, interquartile range 3-16 months). The median follow-up for the survivors was 47 months (interquartile range 37-57 months). The areas under the receiver-operating characteristic curves for predicting mortality at 2 years were 0.77 for both peak VO(2)and VE/VCO(2)slope. With peak VO(2)and VE/VCO(2)slope viewed as continuous variables in the Cox proportional-hazards model, they were both highly significant prognostic indicators, both in univariate analysis and bivariate analysis (P<0.001 for VE/VCO(2)slope, P<0.003 for peak VO(2)).
Lower peak VO(2)implies poorer prognosis across a range of values from 10 to 20 ml. kg(-1)min(-1), without a unique threshold. Gradations of elevation of the VE/VCO(2)slope also carry prognostic information over a wide range (30-55). The two parameters are comparable in terms of prognostic power, and contribute complementary prognostic information.
慢性心力衰竭预后较差。心肺运动试验有助于预测生存率。我们旨在确定一系列阈值下峰值摄氧量（VO₂）和通气当量（VE/VCO₂）斜率的预后价值。
1992年至1996年间，303例连续的稳定慢性心力衰竭患者接受了心肺运动试验。他们的年龄为59±11岁（均值±标准差），峰值VO₂为17.8±6.6 ml·kg⁻¹·min⁻¹，VE/VCO₂斜率为37±12。在1999年1月随访结束时，91例患者死亡（中位时间为7个月，四分位间距为3 - 16个月）。幸存者的中位随访时间为47个月（四分位间距为37 - 57个月）。预测2年死亡率的受试者工作特征曲线下面积，峰值VO₂和VE/VCO₂斜率均为0.77。在Cox比例风险模型中，将峰值VO₂和VE/VCO₂斜率视为连续变量时，它们在单变量分析和双变量分析中均为高度显著的预后指标（VE/VCO₂斜率P<0.001，峰值VO₂P<0.003）。
在10至20 ml·kg⁻¹·min⁻¹的一系列值范围内，较低的峰值VO₂意味着预后较差，无独特阈值。VE/VCO₂斜率的升高程度在较宽范围（30 - 55）内也携带预后信息。这两个参数在预后能力方面相当，并提供互补的预后信息。
