老年冠心病患者的心肺运动试验特点及临床意义

Features and clinical significance of cardiopulmonary exercise testing in elderly patients with coronary heart disease

目的观察老年冠心病患者的心肺运动试验（CPET）特点及临床意义。方法回顾性分析2015年9月至2017年8月在郑州大学第五附属医院就诊，行冠状动脉造影并进行CPET的老年患者59例，平均年龄（61．5±3．0）岁。根据其冠状动脉造影结果分为冠心病组40例和非冠心病组19例，比较两组患者CPET参数的差异。根据冠状动脉造影血管狭窄程度将冠心病组分为50％～70％组25例和〉70％组15例，比较两组间摄氧量对应功率的递增斜率在整个运动中的差异和无氧阈前后的变化。结果CPET结果显示，冠心病组患者无氧阈、峰值摄氧量及摄氧量、峰值摄氧量占预计值的百分比、峰值氧脉搏和摄氧量对应功率的递增斜率较非冠心病组降低，分别为（855．8±207．0）ml／min、（1371．5±388．8）ml／min、（18．3±4．7）ml·min-1·kg-1、（65．6±14．8）％、（11．2±2．5）ml／次和（8．0±1．1）ml·min-1·W-1比（976．5±231．8）ml／min、（1652．8±435．5）ml／min、（22．0±4．4）ml·min-1·kg-1、（85．5±14．9）％、（12．9±3．2）ml／次和（9．1±1．5）ml·min-1·W-1（均P〈0．05）。冠心病组患者狭窄程度〉70％组与50％～70％组比较，在整个功率递增运动中和在无氧阂后摄氧量对应功率的递增曲线斜率降低（t=2．815，P=0．008）。结论老年冠心病患者运动耐量下降，且运动过程中，摄氧量对应功率的递增曲线斜率降低，无氧阈后更为明显，可能与运动诱发心肌缺血致左室功能下降，心排血量降低有关。提示CPET可为冠心病患者提供缺血证据。

Objective To examine the features and clinical significance of cardiopulmonary exercise testing（CPET）in elderly patients with coronary heart disease. Methods A retrospective study was conducted at the Fifth Affiliated Hospital of Zhengzhou University from September 2015 to August 2017. Fifty-nine elderly inpatients who had undergone coronary angiography and CPET were enrolled. The mean age was 61.5 years,and there were 48 males and 11 females. Based on the results of coronary angiography, patients were divided into a coronary heart disease （CAD） group （ n = 40） and a non CAD group （n = 19）. Meanwhile, according to the degree of coronary stenosis assessed by angiography, the CAD group was further divided into two subgroups（Group A ： coronary stenosis, 50 % - 70%, n=25; Group B： coronary stenosis, 〉70%, n= 15）. All results of CPET were compared between the groups. Results Patients in the CAD group were significantly associated with a lower anaerobic threshold（855.8±207.0）ml/min vs. （976.5±231.8）ml/min,a lower peak VO2 （1 371.5± 388.8）ml/min vs. （1652.8±435.5）ml/min,a lower percentage of peak VO2 （18.3±4.7）ml · min-1 · kg -1 vs. （22.0±4.4）ml. min-1 · kg -1,a lower peak O2-pulse（65.6±14.8）% vs. （85.5±14.9）% and a lower △VO2/AWR slope to expected value（8.0±1.1）ml · min- 1· W- 1 vs. （9.1±1.5）ml · min-1· W- 1,compared with those in the non-CAD group（all P〈0.05）.However, there was no significant difference in other indexes between the groups. Furthermore, in the CAD group, △VO2/ △WRall - Ex ,△VO2/△WR〉AT and △VO2/△WR Ratio to expected value were lower in Group B（ 7. 5 ± 1.3 vs. 8.3±1.0,t=2.317,P=0.026）,（6.2±1.9 vs. 7.6±1.2,t=2.815,P=0. 008）and（0.7± 0. 2vs. 0.9 ±0.1, t = 2.957, P = 0. 005 ）. There was no difference in △VO2/△WR〈AT （P 〉 0.05 ）. Conclusions Exercise tolerance is lower in elderly CAD patients than those without CAD,and △VO2/△WR is decreased during the process of exercise, especially after the AT, which may be associated with low cardiac output due to left ventricular myocardial ischemia. This finding suggests that CPET can provide evidence of ischemia in patients with coronary heart disease and is valuable for the development of diagnostic and therapeutic strategies.