Hoshimoto-Iwamoto Masayo, Koike Akira, Nagayama Osamu, Tajima Akihiko, Suzuki Takeya, Uejima Tokuhisa, Sawada Hitoshi, Aizawa Tadanori
The Cardiovascular Institute, Minato-ku, Tokyo, 106-0032, Japan.
J Physiol Sci. 2009 Jan;59(1):49-55. doi: 10.1007/s12576-008-0004-8. Epub 2008 Nov 30.
We compared the prognostic power of end-tidal CO(2) pressure (PETCO(2)) during exercise, an index of arterial CO(2) pressure, with those of established respiratory gas indexes during exercise testing in patients with left ventricular dysfunction. Seventy-eight consecutive patients with a left ventricular ejection fraction (LVEF) <or=40% were enrolled in the study. All the patients performed a symptom-limited incremental exercise test with respiratory gas measurements. PETCO(2) at peak exercise, peak O(2) uptake (VO(2)), the ratio of the increase in ventilation to the increase in CO(2) output (VE/VCO(2) slope), and the ratio of the increase in VO(2) to the increase in work rate (deltaVO(2)/deltaWR) were measured. PETCO(2) at peak exercise was significantly correlated with peak VO(2), VE/VCO(2) slope and deltaVO(2)/deltaWR. During a prospective follow-up period of 992 +/- 570 days, 14 cardiac deaths occurred. As compared to survivors, non-survivors had a significantly lower LVEF, lower PETCO(2) at peak exercise, lower peak VO(2), lower deltaVO(2)/deltaWR and a higher VE/VCO(2) slope. Among these indexes, only PETCO(2) at peak exercise was found to be an independent predictor for cardiac death. PETCO(2) at peak exercise is useful in predicting poor prognosis in patients with left ventricular systolic dysfunction.
我们比较了运动期间呼气末二氧化碳分压（PETCO₂）（一种动脉二氧化碳分压指标）与左心室功能不全患者运动测试期间既定呼吸气体指标的预后预测能力。连续纳入78例左心室射血分数（LVEF）≤40%的患者进行研究。所有患者均进行了症状限制性递增运动测试并测量呼吸气体。测量了运动峰值时的PETCO₂、峰值摄氧量（VO₂）、通气量增加与二氧化碳排出量增加的比值（VE/VCO₂斜率）以及VO₂增加与工作负荷增加的比值（deltaVO₂/deltaWR）。运动峰值时的PETCO₂与峰值VO₂、VE/VCO₂斜率和deltaVO₂/deltaWR显著相关。在992±570天的前瞻性随访期内，发生了14例心源性死亡。与幸存者相比，非幸存者的LVEF显著更低，运动峰值时的PETCO₂更低，峰值VO₂更低，deltaVO₂/deltaWR更低，而VE/VCO₂斜率更高。在这些指标中，仅发现运动峰值时的PETCO₂是心源性死亡的独立预测因素。运动峰值时的PETCO₂有助于预测左心室收缩功能不全患者的不良预后。
