摘要目的 通过对左心室射血分数(LVEF)正常的急性ST段抬高心肌梗死(STEMI)患者进行心肺运动试验(CPET),评价早期心脏功能受损与运动耐量的相关性.方法 研究入选2007年9月至2011年12月初次发生急性STEMI且LVEF≥50％的患者共229例,回顾性分析患者发病后早期CPET测定的峰值摄氧量(Vo2peak)和无氧阈值摄氧量(Vo2AT)与超声心动图测量的心脏结构及功能指标的相关关系.结果 患者平均年龄(56.2±11.1)岁,男性占86.9％,LVEF为60.2％±6.9％,Vo2peak和Vo2AT分别为(21.8 ±5.7)ml·kg-1·min-1和(19.4±4.8)ml·kg-1·min-1.Vo2peak与LVEF(r=0.17,P=0.012)、舒张早期最大峰值流速(E峰)与舒张晚期最大峰值流速(A峰)比值(E/A)(r=0.15,P=0.033)和心肌收缩期峰值速度(Sm)(r=0.30,P＜0.001)呈正相关,与A峰(r=-0.20,P=0.005)、E峰与心肌舒张早期峰值速度(Em)比值(E/Em)(r=-0.16,P=0.022)和左房压(LAP)(r=-0.16,P=0.021)呈负相关；而Vo2AT仅与LAP(r=-0.17,P=0.031)呈负相关.经多因素校正后,Vo2peak与LVEF(β=0.149,s=0.051,sβ=0.178,95％ CI0.048 ～0.250,P =0.004)和Sm(β=0.606,s=0.167,sβ=0.245,95％ CI 0.277 ～0.936,P＜0.001)、以及Vo2AT与LAP(β=-0.271,s=0.117,sβ=-0.172,95％ CI-0.501 ～-0.040,P=0.022)的相关性仍独立存在.结论 急性STEMI患者早期心脏收缩和舒张功能受损即可导致运动耐量下降,CPET是反映心脏功能状态的敏感检测手段.

abstractsObjective To explore the relationship between early heart function impairment and exercise tolerance in patients with acute ST-elevation myocardial infarction (STEMI) and normal left ventricular ejection fraction (LVEF).Methods A total of 229 patients with a LVEF of ≥ 50％ were retrospectively reviewed.There were 199 males and 30 females with a mean age of 56.2 ± 11.1 years.They underwent cardiopulmonary exercise testing (CPET) early after STEMI in a single exercise laboratory.Demographic data,presence of concomitant diseases,characteristics of STEMI,echocardiography and CPET findings were evaluated.Results Their mean LVEF was 60.2％ ± 6.9％ and the values of Vo2peak and Vo2AT were (21.8 ±5.7) ml · kg-1 · min-1 and (19.4 ±4.8) ml · kg-1 · min-1 respectively.Peak oxygen uptake (Vo2peak) showed a positive correlation with LVEF (r =0.17,P =0.012),E/A (r =0.15,P =0.033) and peak myocardial systolic velocity (Sm) (r =0.30,P ＜ 0.001).On the contrary,it varied inversely with peak A wave velocity (A) (r =-0.20,P =0.005),E/Em (r =-0.16,P =0.022) and left atrial pressure (LAP) (r =-0.16,P =0.021).And there was a similar correlation between oxygen uptake at anaerobic threshold (Vo2AT) and LAP (r =-0.17,P =0.031).After adjustments of subject demographic features and cardiovascular risk factors,Vo2peak was still associated with LVEF (β =0.149,s =0.051,sβ=0.178,95％CI0.048-0.250,P=0.004) and Sm (β =0.606,s=0.167,sβ=0.245,95％ CI 0.277-0.936,P ＜0.001).So did the relationship between Vo2AT and LAP (β =-0.271,s =0.117,sβ =-0.172,95％CI-0.501--0.040,P =0.022).Conclusion The exercise tolerance may be affected by early heart function impairment in STEMI patients.CPET is a sensitive detection tool of decreased heart function.