Transthoracic echocardiography using pulsed Doppler at the aortic annulus accurately assessed cardiac output in rats compared to thermodilution (r = 0.93; P < 0.0001, bias -3 ml/min).
Does transthoracic echocardiography accurately measure cardiac output compared to thermodilution in rats?
Transthoracic echocardiography using pulsed Doppler at the aortic annulus provides accurate and precise measurements of cardiac output in rats compared to thermodilution.
Effect estimate: r = 0.93
p-value: p=< 0.0001
The systematic evaluation of different transthoracic echocardiographic (TTE) methods to determine cardiac output (CO) and the effect of changes in intravascular volume on echocardiographically determined indexes of cardiovascular structure in the rat has not been documented. With the use of 11 Wistar rats, simultaneous echocardiographic and thermodilution measurements of CO were compared at baseline and after blood withdrawal or transfusion at 43 different levels of intravascular volume and using 10 different echocardiographic approaches. The best correlation (r = 0.93; P < 0.0001), least bias (-3 ml/min), and best precision (16 ml/min) between thermodilution and echocardiographic methods were obtained at the level of aortic annulus using pulsed Doppler. In conclusion, CO could be accurately assessed in rats using TTE and pulsed Doppler at the level of the aortic annulus. This annulus was demonstrated to remain stable, but pulmonary annulus, thoracic aorta, mitral valve, and left ventricular diameters were found to be more modifiable during volumic changes.
Slama et al. (Sat,) reported a other. Transthoracic echocardiography (pulsed Doppler at aortic annulus) vs. Thermodilution was evaluated on Correlation of cardiac output measurement between echocardiography and thermodilution (r = 0.93, p=< 0.0001). Transthoracic echocardiography using pulsed Doppler at the aortic annulus accurately assessed cardiac output in rats compared to thermodilution (r = 0.93; P < 0.0001, bias -3 ml/min).