RESUMO
Ten healthy Beagle dogs were used to compare selected echocardiographic parameters of right ventricular (RV) systolic function with high field cardiac magnetic resonance imaging (MRI). All dogs underwent complete transthoracic echocardiography before and during anesthesia, as well as cardiac MRI with determination of morphology-based ejection fraction, and phase contrast angiography-derived stroke volume. A correlation analysis was carried out between echocardiographic and MRI parameters. The values of fractional area change, tricuspid annular plane systolic excursion, tissue Doppler imaging derived peak velocity of the isovolumic contraction wave and systolic wave of the lateral tricuspid valve annulus showed lower values under general anesthesia. Of all echocardiographic parameters of RV systolic function, only fractional area change (r = 0.671, P = 0.034) and tissue Doppler imaging derived peak velocity of the systolic wave of the lateral tricuspid valve annulus (r = 0.768; P = 0.01), showed a significant correlation with MRI derived stroke volume. None of the echocardiographic parameters correlated with MRI derived ejection fraction. When evaluating the RV echocardiographically, fractional area change and peak velocity of the systolic wave of the lateral tricuspid valve annulus appear to be the most reliable predictors of RV systolic function when compared to MRI under anesthesia.
