Amory H, Votion D-M, Fraipont A, Goachet A G, Robert C, Farnir F, Van Erck E
Equine Clinic, Clinical Department of Companion Animals and Equids, Faculty of Veterinary Medicine, University of Liege, Sart Tilman, Liege, Belgium.
Equine Vet J Suppl. 2010 Nov(38):216-9. doi: 10.1111/j.2042-3306.2010.00253.x.
It is unknown whether or not exercise-induced cardiac fatigue (EICF), as demonstrated in human athletes performing long duration exercise, occurs in endurance horses.
To examine the effects of a long distance endurance race on left ventricular systolic function in horses.
Echocardiography was performed before, and after, a 2 or 3 star international endurance race (106-132 km) in 11 horses. Systolic (s) and diastolic (d) interventricular and left ventricular free wall thickness (IVS and LVFW, respectively), left ventricular, left atrial and aortic internal diameter (LVID, LA and Ao, respectively), fractional shortening (FS) and ejection fraction (EF) were measured by echocardiography. Heart rate (HR), peak flow velocity (Vmax), flow velocity integral (FVI), ejection time (ET), pre-ejection period (PEP), velocity of circumferential fibre shortening (Vcf), stroke volume (SV) and cardiac output (CO) were measured from aortic Doppler wave recordings.
After the race, LVIDd, Ao, LA, EF, FS, FVI, SV, ET and ET indexed for HR were significantly lower and IVSd, LVFWd, HR, PEP, PEP/ET and Vcf significantly higher as compared with prerace values. Pre- to post exercise changes in those parameters were not significantly correlated with changes in HR or in LVIDd.
Results suggest that EICF, with a decrease in left ventricular systolic function, could occur post exercise in horses performing long duration endurance races. However, a multanecus effect of altered preload and heart rate on the studied variables cannot be discounted.
在进行长时间运动的人类运动员中所表现出的运动诱发的心脏疲劳（EICF）在耐力马匹中是否会出现尚不清楚。
研究长距离耐力赛对马匹左心室收缩功能的影响。
对11匹马在参加二星级或三星级国际耐力赛（106 - 132千米）之前和之后进行超声心动图检查。通过超声心动图测量收缩期（s）和舒张期（d）的室间隔及左心室游离壁厚度（分别为IVS和LVFW）、左心室、左心房及主动脉内径（分别为LVID、LA和Ao）、缩短分数（FS）和射血分数（EF）。从主动脉多普勒波记录中测量心率（HR）、峰值流速（Vmax）、流速积分（FVI）、射血时间（ET）、射血前期（PEP）、圆周纤维缩短速度（Vcf）、每搏输出量（SV）和心输出量（CO）。
比赛后，与赛前值相比，LVIDd、Ao、LA、EF、FS、FVI、SV、ET以及校正心率后的ET显著降低，而IVSd、LVFWd、HR、PEP、PEP/ET和Vcf显著升高。这些参数运动前后的变化与HR或LVIDd的变化无显著相关性。
结果表明，在进行长时间耐力赛的马匹运动后可能会出现EICF，并伴有左心室收缩功能下降。然而，前负荷和心率改变对所研究变量的多因素影响也不能忽视。
