Lauer Michael S, Pothier Claire E, Magid David J, Smith S Scott, Kattan Michael W
Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Ann Intern Med. 2007 Dec 18;147(12):821-8. doi: 10.7326/0003-4819-147-12-200712180-00001.
The exercise treadmill test is recommended for risk stratification among patients with intermediate to high pretest probability of coronary artery disease. Posttest risk stratification is based on the Duke treadmill score, which includes only functional capacity and measures of ischemia.
To develop and externally validate a post-treadmill test, multivariable mortality prediction rule for adults with suspected coronary artery disease and normal electrocardiograms.
Prospective cohort study conducted from September 1990 to May 2004.
Exercise treadmill laboratories in a major medical center (derivation set) and a separate HMO (validation set).
33,268 patients in the derivation set and 5821 in the validation set. All patients had normal electrocardiograms and were referred for evaluation of suspected coronary artery disease.
The derivation set patients were followed for a median of 6.2 years. A nomogram-illustrated model was derived on the basis of variables easily obtained in the stress laboratory, including age; sex; history of smoking, hypertension, diabetes, or typical angina; and exercise findings of functional capacity, ST-segment changes, symptoms, heart rate recovery, and frequent ventricular ectopy in recovery.
The derivation data set included 1619 deaths. Although both the Duke treadmill score and our nomogram-illustrated model were significantly associated with death (P < 0.001), the nomogram was better at discrimination (concordance index for right-censored data, 0.83 vs. 0.73) and calibration. We reclassified many patients with intermediate- to high-risk Duke treadmill scores as low risk on the basis of the nomogram. The model also predicted 3-year mortality rates well in the validation set: Based on an optimal cut-point for a negative predictive value of 0.97, derivation and validation rates were, respectively, 1.7% and 2.5% below the cut-point and 25% and 29% above the cut-point.
Blood test-based measures or left ventricular ejection fraction were not included. The nomogram can be applied only to patients with a normal electrocardiogram. Clinical utility remains to be tested.
A simple nomogram based on easily obtained pretest and exercise test variables predicted all-cause mortality in adults with suspected coronary artery disease and normal electrocardiograms.
对于冠状动脉疾病预检概率为中到高的患者，推荐进行运动平板试验以进行风险分层。试验后风险分层基于杜克运动平板评分，该评分仅包括功能能力和缺血指标。
为疑似冠状动脉疾病且心电图正常的成年人开发并外部验证一种运动平板试验后的多变量死亡率预测规则。
1990年9月至2004年5月进行的前瞻性队列研究。
一个主要医疗中心的运动平板实验室（推导集）和一个独立的健康维护组织（验证集）。
推导集有33268例患者，验证集有5821例患者。所有患者心电图均正常，因疑似冠状动脉疾病而接受评估。
对推导集患者进行了中位时间为6.2年的随访。基于在压力实验室中容易获得的变量推导了一个列线图所示模型，这些变量包括年龄、性别、吸烟、高血压、糖尿病或典型心绞痛病史，以及功能能力、ST段改变、症状、心率恢复和恢复时频繁室性早搏的运动结果。
推导数据集包括1619例死亡病例。虽然杜克运动平板评分和我们的列线图所示模型均与死亡显著相关（P<0.001），但列线图在区分度（右删失数据的一致性指数，0.83对0.73）和校准方面表现更好。基于列线图，我们将许多杜克运动平板评分处于中到高风险的患者重新分类为低风险。该模型在验证集中对3年死亡率的预测也很好：基于阴性预测值为0.97的最佳切点，推导集和验证集中低于切点的比例分别为1.7%和2.5%，高于切点的比例分别为25%和29%。
未纳入基于血液检测的指标或左心室射血分数。该列线图仅适用于心电图正常的患者。临床实用性仍有待检验。
一个基于容易获得的预检和运动试验变量的简单列线图可预测疑似冠状动脉疾病且心电图正常的成年人的全因死亡率。
