Chua T P, Ponikowski P, Harrington D, Anker S D, Webb-Peploe K, Clark A L, Poole-Wilson P A, Coats A J
Royal Brompton Hospital and National Heart and Lung Institute, Imperial College School of Medicine, London, England, United Kingdom.
J Am Coll Cardiol. 1997 Jun;29(7):1585-90. doi: 10.1016/s0735-1097(97)00078-8.
This study sought to investigate the clinical characteristics of patients with chronic heart failure and an increased ventilatory response to exercise and to examine the prognostic usefulness of this response.
The ventilatory response to exercise is increased in many patients with chronic heart failure and may be characterized by the regression slope relating minute ventilation to carbon dioxide output (VE-VCO2 slope) during exercise.
One hundred seventy-three consecutive patients (155 men; mean [+/-SD] age 59.8 +/- 11.5 years; radionuclide left ventricular ejection fraction [LVEF] 28.4 +/- 14.6%) underwent cardiopulmonary exercise testing (peak oxygen consumption 18.5 +/- 7.3 ml/kg per min; VE-CO2 slope 34.8 +/- 10.6) over a 2-year period. Using 1.96 standard deviations above the mean VE-VCO2 slope of 68 healthy age-matched subjects (mean slope 26.3 +/- 4.1), we defined a high ventilatory response to exercise as a slope >34.
Eighty-three patients (48%) had an increased VE-VCO2 slope (mean 43.1 +/- 8.9). There was a difference in age (62.2 vs. 57.3 years, p = 0.005), New York Heart Association functional class (2.9 vs. 2.1, p < 0.001), LVEF (24.7 vs. 31.9%, p = 0.0016), peak oxygen consumption (14.9 vs. 21.7 ml/kg per min, p < 0.0001) and radiographic cardiothoracic ratio (0.58 vs. 0.55, p = 0.002) between these patients and those with a normal slope. In the univariate Cox proportional hazards model, the E-VCO2 slope was an important prognostic factor (p < 0.0001). In the multivariate Cox analyses using several variables (age, peak oxygen consumption, VE-VCO2 slope and LVEF), the VE-VCO2 slope gave additional prognostic information (p = 0.018) beyond peak oxygen consumption (p = 0.022). Kaplan-Meier survival curves at 18 months demonstrated a survival rate of 95% in patients with a normal VE-VCO2 slope compared with 69% in those with a high slope (p < 0.0001).
A high VE-VCO2 slope selects patients with more severe heart failure and is an independent prognostic marker. The VE-VCO2 slope may be used as a supplementary index in the assessment of patients with chronic heart failure.
本研究旨在调查慢性心力衰竭患者且运动时通气反应增加的临床特征，并检验这种反应的预后价值。
许多慢性心力衰竭患者运动时的通气反应增加，其特征可能为运动期间分钟通气量与二氧化碳排出量的回归斜率（VE-VCO2斜率）。
在两年期间，173例连续患者（155例男性；平均[±标准差]年龄59.8±11.5岁；放射性核素左心室射血分数[LVEF]28.4±14.6%）接受了心肺运动试验（峰值耗氧量18.5±7.3 ml/kg每分钟；VE-CO2斜率34.8±10.6）。使用68例年龄匹配的健康受试者平均VE-VCO2斜率（平均斜率26.3±4.1）加1.96个标准差，我们将运动时高通气反应定义为斜率>34。
83例患者（48%）VE-VCO2斜率增加（平均43.1±8.9）。这些患者与斜率正常的患者在年龄（62.2对57.3岁，p = 0.005）、纽约心脏协会功能分级（2.9对2.1，p < 0.001）、LVEF（24.7对31.9%，p = 0.0016）、峰值耗氧量（14.9对21.7 ml/kg每分钟，p < 0.0001）和胸部X线心胸比率（0.58对0.55，p = 0.002）方面存在差异。在单变量Cox比例风险模型中，E-VCO2斜率是一个重要的预后因素（p < 0.0001）。在使用多个变量（年龄、峰值耗氧量、VE-VCO2斜率和LVEF）的多变量Cox分析中，VE-VCO2斜率除了峰值耗氧量（p = 0.022）外还提供了额外的预后信息（p = 0.018）。18个月时的Kaplan-Meier生存曲线显示，VE-VCO2斜率正常的患者生存率为95%，而斜率高的患者为69%（p < 0.0001）。
高VE-VCO2斜率筛选出心力衰竭更严重的患者，是一个独立的预后标志物。VE-VCO2斜率可作为评估慢性心力衰竭患者的补充指标。
