Echocardiographic changes related to exercise
The echocardiographic parameters were presented in Table 2.
Prior to exercise the values of LVIDd, LVIDs, EDV, SV and LA were 9.08 ± 0.34, 5.63 ± 0.26, 470.00 ± 37.41, 295.42 ± 24.20 and 7.59 ± 0.23 respectively. After exercise the values were 10.03 ± 0.24, 6.24 ± 0.19, 568.56 ± 28.70, 385.42 ± 23.77 and 8.43 ± 0.24 respectively. The values of echocardiographic parameters were increased after exercise when compared to before exercise. Highly significant increase in LVIDd, LVIDs, EDV, SV and LA were seen after exercise.
Prior to exercise the values of LVPWd, ESV, EF, FS, and Ao were 2.30 ± 0.14, 167.00 ± 15.13, 62.23 ± 1.40, 35.29 ± 1.02 and 6.24 ± 0.16 respectively. After exercise the values were 2.67 ± 0.20, 197.54 ± 14.16, 67.76 ± 2.30, 40.51 ± 1.90 and 6.70 ± 0.20 respectively. Significant increase in LVPWd, ESV, EF, FS, and Ao were seen after exercise.
Left atrial dimension and left ventricular internal diameter during diastole and systole, left ventricular posterior wall during diastole, aortic diameter, end diastole volume, end systole volume, stroke volume, ejection fraction and fractional shortening increased significantly after exercise when compared to pre-exercise values.
Mild aortic regurgitation was noted on three horses after exercise (Fig. 5) . Prior to the exercise there was no identifiable aortic, mitral and tricuspid regurgitation in all horses.