Measurement Variation and Repeatability of Echocardiographic Variables Used to Estimate Pulmonary Artery Pressure in Dogs.

With regard to repeatability, VTR is superior to other methods used for echocardiographic estimation of systolic pulmonary artery pressure. When TR is absent, the acceleration time of pulmonary ejection and the acceleration-to-ejection time ratio are alternative measures. A change in VTR exceeding 0.3 m/s might be outside the range of expected within-operator variation.