Evaluation of age‐dependent changes of myocardial velocity using pulsed wave and colour tissue Doppler imaging in adult warmblood horses

Abstract

Our aim was to evaluate the influence of the ageing process on the myocardium using pulsed wave tissue Doppler (PW-TDI) and colour tissue Doppler imaging (cTDI) to measure myocardial velocities at three different myocardial regions (right ventricular free wall: RVFW, interventricular septum: IVS, left ventricular free wall: LVFW). A total of 60 healthy warmblood horses, aged from 3 to 30 years, were examined. The horses were divided into five age groups (group 1: 3-8 years, n = 14; group 2: 9-13 years, n = 9; group 3: 14-18 years, n = 10; group 4: 19-23 years, n = 14; group 5: 24-30 years, n = 10). The results showed that age has a significant influence on the radial myocardial velocity of horses in different myocardial regions. This influence was detectable by both echocardiographic techniques, although PW-TDI measurements showed a higher reproducibility due to lower intraindividual variation coefficients. Systolic contraction velocity (p ≤ 0.01) and early diastolic relaxation velocity (p ≤ 0.001) in the LVFW decreased significantly with ageing, while late diastolic contraction velocity increased (0.001 < p ≤ 0.01). Early and late diastolic contraction velocities at the IVS increased significantly with ageing (p ≤ 0.001). Systolic and late-diastolic contraction velocities at the RVFW increased significantly with ageing (p ≤ 0.001). The results indicated a decrease in left ventricular contraction ability and reduced myocardial relaxation and altered diastolic function in the right ventricle with increasing age. These functional changes may be signs of age-related structural myocardial changes or cardiac remodelling, such as increased myocardial stiffness. Thus, an assessment of the radial myocardial velocities of a horse's heart with TDI should always consider physiological age-related changes in contractility. Comparing the two examination techniques (PW-TDI and cTDI) we used in our study, we found that both methods showed comparable age-related alterations. Nevertheless, differences in absolute values were found with a tendency of higher values using PW-TDI in comparison to cTDI.

Cardiovascular Particularities in Pega Breed Donkeys (Equus asinus)

“…Several studies describe cardiovascular affections in horses, as well as electrocardiographic patterns (Fernandes et al 2004;Dantas et al 2014), echocardiographic patterns in the species (Gehlen and Bildheim 2018;Marr 2019;Almeida 2009;Siwinska et al 2019) in foals (Freccero et al 2018) also related to weight, sex and age, as well as common changes in the category of athlete animals (Reef et al 2014). According to the echocardiographic parameters obtained in the present study, donkeys seem to have lower values for these parameters in horses, as described in the literature.…”

Age‐related differences in blood pressure, ultrasound‐derived arterial diameters and arterial wall stiffness parameters in horses

“…This finding, in combination with a similar decrease in CO (18% found in this study vs 22% in human patients 33 ), might explain why no increase in SAP, nor a decrease in DAP and thus no widening in the PP was found in our study. This decrease in CO can be explained by the lower plasma volume 34 and altered ventricular function in older horses 35 . The limitation of our study, which can also explain why small differences in blood pressure might be not detected, is the non‐invasive measurement of the arterial blood pressure.…”

Preliminary study on the effects of pergolide on left ventricular function in the horses with pituitary pars intermedia dysfunction

“…Furthermore, younger horses received a treatment more often than older horses. The inhomogeneous distribution of ages could have affected our results as a reduced diastolic function with compensatory increased A myocardial velocity with advancing ages has been reported in horses [ 22 24 29 ] and in humans [ 30 31 ]. However, the regression analyses did not show an effect of age on A myocardial velocity or E/A ratio.…”

“…The echocardiographic exam also included tissue Doppler echocardiography (TDE) on a right-sided short axis view at a level just below the mitral valve and a minimum of three heart cycles were recorded for each measurement [ 21 22 23 ]. The sampling gate for the pulsed-wave TDE (pw-TDE) was placed subendothelial during diastole either in the interventricular septum (IVS) or in the left ventricular free wall (LFW) and recordings were stored with a time velocity scale from −20 to + 20 cm/s.…”