Fachbereich Veterinärmedizin



    Einfluss des Alters auf die echokardiografischen Untersuchungsparameter junger Warmblutpferde (2017)

    Lagershausen, Henrike Luise (WE 17)
    Berlin: Mensch und Buch Verlag, 2017 — XVI, 185 Seiten
    ISBN: 978-3-86387-822-1
    URL (Volltext): http://www.diss.fu-berlin.de/diss/receive/FUDISS_thesis_000000105185
    Klinik für Pferde, allgemeine Chirurgie und Radiologie

    Oertzenweg 19 b
    14163 Berlin
    +49 30 838 62299

    Abstract / Zusammenfassung

    In this study young German warmblood horses from foals to three-year-olds were examined by echocardiography for the first time. The aim of this study was to determine in which normal range the standard echocardiographic parameters, the tissue Doppler parameters and myocardial strain parameters are located. Furthermore the influence of age and growth on the development of these echocardiographic parameters should be evaluated. The focus of this work was put on the examination of the horse’s heart by the Tissue Doppler Echocardiography which is still novel in equine medicine. Additionally the deformation parameters strain and strain rate were measured by 2D-Speckle Tracking, which are applied to be regional parameters of the ventricular function and beyond that they are independent of angle and global heart movement. As variables of influence, age, weight, height, and sex as well as heart frequency were tested. A total number of 57 warmblood horses at the age of three weeks to three years were examined, which we allocated into 4 age groups (foals, yearlings, two-year-olds and three-year-olds). After the standard B- and M-mode echocardiographic examination, three consecutive heart cycles in the short axis view were stored in Colour Tissue Doppler mode and Spectral Tissue Doppler mode respectively. Out of these data, the systolic, early-diastolic and late-diastolic myocardial velocities in the left free ventricular wall, the interventricular septum and the right ventricular wall as well as the isovolumetric contraction in the left free ventricular wall were determined. For measuring strain and strain rate, three consecutive B-mode heart cycles in the short axis view were recorded. The heart frequency of the foals were significantly higher than the heart frequency of the other groups (P<0,001). All B- and M-mode parameters increased from foals to three-year-olds with significant changes between the four groups. The major impact on the development of the B-mode parameters was detected for the weight of the horses. Weight and height had the major impact on the M-mode parameters. Sex only showed impact on the parameters sporadically, but since the distribution of sex in the four age groups was not balanced, the effects could be accidentally. The early-diastolic and late-diastolic mycodial velocities in the left free ventricular wall
    interventricular septum the systolic and early-diastolic myocardial velocity showed a tendency to increase. In the right ventricular wall, only the early-diastolic myocardial velocity slightly increased. Heart frequency and height had the major impact on the development of the myocardial velocities. Similarly the early-diastolic and late-diastolic myocardial velocity measured by Spectral Tissue Doppler increased from foals to the young adult horses as detected with Colour Tissue Doppler. Furthermore the early-diastolic myocardial velocity in the right ventricular wall showed the tendency to increase. Heart frequency and weight had major impact on these parameters measured by spectral tissue Doppler. The radial strain in the interventricular septum, measured by 2D-Speckle Tracking, increased by trend while the systolic radial strain rate decreased. In the left ventricular free wall the systolic as well as the early diastolic radial strain rate decreased with age. The major impact on the development of strain and strain rate had heart frequency and height. It is impossible to distinguish the different impacts on the parameters clearly. Height, weight, age and heart frequency are all closely related to the growth of the horse and influence each other substantially. Eventually our results indicate that the growth of the horses overall has a great impact on the parameter value and consequently age also has a notable impact. The partial great impact of the heart frequency must be taken into account when evaluating the data. Due to the difficult acquisition of data in the young foals and horses it is recommended to sedate the horses during examination for achieving lower data variability. Subsequent studies have to evaluate the impact of sedation on the echocardiographic parameters in foals and young horses. measured by Colour Tissue Doppler increased from foals to three-year-olds. In the