Two-dimensional, M-mode and Doppler-derived echocardiographic parameters in sedated healthy growing female sheep

Abstract

Despite the fact that sheep are a widely used animal model in cardiovascular research, reference values for transthoracic echocardiography in normal growing animals are not available. Eight healthy female lambs underwent two-dimensional, M-mode and pulsed wave Doppler echocardiographic examination at 100 days of age and every three months thereafter over a 12-month period. The study was conducted under sedation with midazolam, butorphanol and constant rate infusion of intravenous propofol. Their growth phase was completed at about one year of age. All the echocardiographic parameters considered were significantly correlated with body weight and age class except for the left ventricular systolic and diastolic diameters. Functional indices were not correlated to body weight or age except for the E-point to septal separation distance (EPSS). Doppler-derived parameters were not influenced by independent variables. Transthoracic echocardiography can be considered an applicable method for cardiovascular research using a growing lamb animal model after appropriate adjustments for age and body size.

M-mode echocardiographic reference values in Pantja goats

“…This might be explained by the fact that with increase in BW, cardiac size increases and with increase in cardiac size, cardiac volume and CO also increases. A weak negative correlation of FS and EF with BW in Pantja goats was in accordance with previous findings in sheep [ 21 ]. Variation in the observation of these parameters can be explained by the fact that FS and EF are influenced by many parameters which include preload, afterload and contractility, all of which may act independently or in combination to affect this parameter [ 16 ].…”

“…BW correlated significantly (p<0.01) with most M-mode echocardiographic parameters (LVDd, LVDs, IVSd, LVPWd, LVPWs, EDV, ESV, SV, CO, LAs, AOd, LAPWs, DE amplitude, and EPSS) in Pantja goats (Tables- 2 and 3 ). Similar findings were observed in Philippine sheep and sedated healthy growing female sheep [ 19 , 21 ]. It is seen that as BW of animal increases, the heart size also increases, and this might have contributed to the above findings.…”

“…It is seen that as BW of animal increases, the heart size also increases, and this might have contributed to the above findings. Significant (p<0.01) positive correlation between BW and IVSd, LVPWd and LVPWs in Pantja goats (Tables- 2 and 3 ) was in accordance with findings in sedated healthy growing female sheep [ 21 ]. Left ventricular volumes, viz., EDV, ESV, SV, and CO showed significant (p<0.01) correlation with BW (Tables- 2 and 3 ).…”

Aortic stenting in the growing sheep causes aortic endothelial dysfunction but not hypertension: Clinical implications for coarctation repair

“…After sedation the animal was positioned in the right lateral recumbence. The echocardiographic examination was performed according to the previously described protocol …”

Ovine Model of Ischemic Mitral Regurgitation

“… BSA (m 2 ) = 0.84 X body weight (Kg) 0.66 Several studies have proposed reference values for echocardiographic parameters in healthy sheep[46,49–51]. However, care should be taken for interpretation of the results because the parameters will be affected by using sedatives or anesthetic agents.…”