In this study, the heart structures of 30 English racing horses with different weights were examined by M-mode echocardiography. Horses were separated into 3 groups of 10 horses. Group A consisted of the horses weighing between 350 and 400 kg, group B between 400 and 450 kg, and group C between 450 and 500 kg. M-mode sections were taken from transducer I (M. papillaris), transducer II (C. tendinei), transducer III (Mitral valve) and trans- ducer IV (Aortic root) using 2-D and measurements were made in four standard-transducer positions. The internal dimension of the left ventricle, the myocardial thickness of the interventricular septum and the left ventricle, and the posterior wall of the left ven- tricle, the ejection phase indices (%FS, %EF) of the left ventricle and the aortic root diameters (AOW) were measured and compar- isons were made among the groups. At the end of this study, no statistical diffence was observed in the parameters obtained from the English racing horses of different weights at the same transducer position. There was a statistically significant increase in the diastolic internal dimension of the left ventricle (LVID-d) in C group horses between transducer I and III positions, the left ventricle systolic internal dimension (LVID-s) in A group horses between transducer I and III and C group horses between transducer I and III positions. In addition, in group B, the measurements of transducer I and III, and transducer II and III were also statistically significant (p

In this study, the heart structures of 30 English racing horses with different weights were examined by M-mode echocardiography. Horses were separated into 3 groups of 10 horses. Group A consisted of the horses weighing between 350 and 400 kg, group B between 400 and 450 kg, and group C between 450 and 500 kg. M-mode sections were taken from transducer I (M. papillaris), transducer II (C. tendinei), transducer III (Mitral valve) and trans- ducer IV (Aortic root) using 2-D and measurements were made in four standard-transducer positions. The internal dimension of the left ventricle, the myocardial thickness of the interventricular septum and the left ventricle, and the posterior wall of the left ven- tricle, the ejection phase indices (%FS, %EF) of the left ventricle and the aortic root diameters (AOW) were measured and compar- isons were made among the groups. At the end of this study, no statistical diffence was observed in the parameters obtained from the English racing horses of different weights at the same transducer position. There was a statistically significant increase in the diastolic internal dimension of the left ventricle (LVID-d) in C group horses between transducer I and III positions, the left ventricle systolic internal dimension (LVID-s) in A group horses between transducer I and III and C group horses between transducer I and III positions. In addition, in group B, the measurements of transducer I and III, and transducer II and III were also statistically significant (p