The prevalence and degree of DEE-PAH were related to the severity of MVD. Changes associated with DEEPAH may be detected in early stages of the disease, but only in dogs with severe mitral valve regurgitation.

TDI provided effective predictors of systolic PAH and demonstrated that both alterations in right-sided systolic and diastolic myocardial function can occur with mild increases in SPAP.

Background: Diagnosis of pulmonary arterial hypertension (PAH) relies on Doppler measurement of pulmonic and tricuspid regurgitation (TR). However, these are not always detectable.Hypothesis: Tissue Doppler imaging (TDI), a novel noninvasive ultrasound technique, provides indirect but sensitive and specific assessment of elevated systolic pulmonary artery pressure (SPAP) in dogs.Animals: One hundred and five dogs with TR. Methods: Prospective observational study. Dogs were categorized as presenting normal (group 1, n 5 45), mildly increased (group 2, n 5 19), or moderately to severely increased (group 3, n 5 41) SPAP, based on TR peak velocities (,2.5, 2.5-3.0, and .3.0 m/s, respectively). Ten quantitative echo-Doppler-and TDI-derived variables were assessed, including the main pulmonary arterial diameter to aortic diameter ratio, pulmonary flow acceleration time, and acceleration-to-ejection time ratio, the Tei index of right ventricular function, and 6 longitudinal basal right ventricular TDI variables.Results: A significant correlation was observed between SPAP and each of the 10 tested variables (P , .05). Conventional echo-Doppler variables were less discriminating than the TDI for predicting increased SPAP. The combined systolic and diastolic right TDI index had the highest sensitivity and specificity (89% and 93% respectively, for a cutoff of 11.8 cm/s) and could discriminate between dogs in group 1 from dogs in group 2.Conclusions and Clinical Importance: TDI provided effective predictors of systolic PAH and demonstrated that both alterations in right-sided systolic and diastolic myocardial function can occur with mild increases in SPAP.

Results suggested that RF is a repeatable and reproducible variable for noninvasive quantitative evaluation of mitral valve regurgitation in awake dogs. Regurgitation fraction also correlated well with disease severity. It appears that this Doppler echocardiographic index may be useful in longitudinal studies of MVD in dogs.

Background: End-systolic volume index (ESVI) is a marker of systolic function, which can be assessed by the geometric (GM, based on Teichholz formula) or 2 planimetric methods (PM, Simpson's derived and length area methods).Hypothesis: Systolic dysfunction (SyD) may be observed in dogs with mitral valve disease (MVD) and is better assessed by PM than GM, which does not take into account the longitudinal left ventricular systolic shortening.Animals: Six healthy dogs were used to determine the variability of the tested variables (Study 1). These variables were then prospectively assessed (Study 2) in 101 small breed dogs: 77 dogs with MVD and 24 healthy controls (CD).Methods: ESVI was measured by GM and PM in awake dogs.Results: All within-and between-day coefficients of variation were o11% (Study 1). For Study 2, a nonlinear overestimation of ESVI was observed by GM compared with PM. PM-derived ESVI was significantly increased in ISACHC class 3 dogs compared with ISACHC class 1 dogs and exerted a significant influence on cardiac events at 5 months in dogs with MVD from ISACHC classes 2 and 3 (P o .05).Conclusions and Clinical Importance: ESVI can be calculated by GM and PM with good repeatability and reproducibility. However, GM overestimates ESVI in a nonlinear way. Therefore, PM-derived ESVI should be preferred for the detection of SyD that is present at the late stages of the disease.