Comparative evaluation of cardiac output using echocardiography in beagle dogs

Abstract

Echocardiographic measurements of cardiac output, including the modified Simpson's method, Automated Contour Tracking(ACT) method, and left ventricular outflow method are well described methods of evaluating cardiac function due to its reliability and the benefits of its non-invasive technique in human medicine. The purpose of this study was to evaluate the accuracy of an echocardiography estimate of cardiac output in isoflurane-anesthetized beagle dogs and was to compare the ACT method to the other methods used in measurement of cardiac output. In healthy beagle dogs, cardiac output results by echocardiography estimate methods showed an excellent correlations with those by the thermodilution method (The modified Simpson's method: r = 0.815, r2 = 0.665, y = 0.434x + 0.311; ACT method: r = 0.86, r2 = 0.748, y = 0.391x + 0.242; ventricular outflow method: r = 0.691, r 2 = 0.478, y = 0.593x + 0.242). Among the results obtained, the ACT method showed the highest correlation coefficient. In conclusion, our study demonstrated that echocardiography estimate methods did not prove to be suitable in accurately measuring absolute cardiac output values but showed an excellent correlation with thermodilution method. Therefore, by using the measurement of cardiac output as supplemental data, echocardiography estimate methods can be used for detection and correction of hemodynamic disturbances during emergency and anesthesia in veterinary practice.