老年冠心病患者心肺运动试验特点

Features of cardiopulmonary exercise testing in elderly patients with coronary arterial disease

目的：了解老年冠心病患者心肺运动试验（CPET）特点。方法选择2010年10月至2014年10月在阜外医院心内科住院行冠状动脉造影，并进行CPET的老年患者，除外急性心肌梗死、左心室射血分数（LVEF）＜55%、恶性心律失常，合并肺部疾病、肺血管疾病、神经肌肉疾病或贫血等，根据冠状动脉造影检查结果分为两组，冠心病组33例和非冠心病组17例，比较其CPET参数。结果共入选患者47例，平均年龄（62.6±4.3）岁，男性32例，女性15例。两组患者年龄、性别、体质量指数、吸烟史、高血压及糖尿病病史无明显差异，超声心动图左心室舒张末内径（LVEDD）及LVEF无明显差异。CPET结果显示，冠心病组峰值氧耗量（peak VO2）和峰值VO2占预计值的百分比（peak VO2%）分别为（1158.4±286.4）ml/min和（60.5±13.4）%，非冠心病组分别为（1382.2±337.9）ml/min和（83.6±14.5）%，冠心病组较非冠心病组明显降低，P＜0.05。冠心病组峰值氧脉搏（peak VO2/HR）明显低于非冠心病组，分别为（10.7±1.6）和（9.5±1.5）ml/（min·beat），P＝0.038。冠心病组氧耗量与功率比值斜率（VO2/WR slope）明显低于非冠心病组，分别为（7.8±0.9）和（6.5±1.5）ml/（min·W），但无氧代谢阈值（AT）及通气效率等无明显差异。结论老年冠心病患者运动耐量较非冠心病患者明显降低，可能与冠心病患者运动时心肌缺血左心室功能不全导致心排血量降低有关。

ObjectiveTo investigate the features of cardiopulmonary exercise testing （CPET） in elderly patients with coronary arterial disease （CAD）.Methods A prospective study was carried out on the elderly patients who hospitalized and underwent coronary angiography and CPET in our center from October 2010 to October 2014. Those patients with acute myocardial infarction, pulmonary disease, left ventricular ejection fraction less than 55% or anaemia were excluded. The obtained 47 patients were divided into CAD （n=33） and non-CAD groups （n=17） according to the results of coronary angiography. Valuables of CPET were compared between the 2 groups of patients.Results The cohort was at an age of （62.6±4.3） years, and included 33 males and 15 females. There was no significant difference in gender, age, body mass index, and histories of cigarettes, hypertension and diabetes. No obvious difference was either seen in left ventricular end diastolic diameter （LVEDD） or left ventricular ejection fraction. CPET results showed that peak VO2 and percentage of it to expected value were lower in CAD group than in non-CAD group [（1158.4±286.4）vs （1382.2±337.9）ml/min], （60.5±13.4）%vs （83.6±14.5）%,P〈0.05]. Peak VO2/HR was also lower in the former than in the latter group [（9.5±1.5）vs （10.7±1.6）ml/（min·beat）,P=0.038）. Compared with non-CAD group, VO2/WR slope was decreased in CAD group [（7.8±0.9）vs （6.5±1.5）ml/（min·W）]. However, there was no difference in anaerobic threshold （AT） or ventilatory equivalent ratio of oxygen and carbon dioxide （VE/VCO2） between the 2 groups.Conclusion Exercise tolerance is decreased in the elderly CAD patients than those without CAD, which may be associated with lower cardiac output for left ventricular dysfunction due to myocardial ischemia.