Pulmonary hypertension in dog: echocardiographic parameters

Various diseases in dogs are associated with pulmonary hypertension (PH), which can be diagnosed, as in humans, by transthoracic echocardiography.

To determine the relation between the right ventricle size and both the severity of pulmonary hypertension and tricuspid regurgitation (TR), 163 dogs of 22 different breeds were included in this prospective study. All dogs were submitted to a complete echocardiographic assessment. 89 showed tricuspid regurgitation pressure gradient (TRPG) equal or superior to 36 mm Hg so they were diagnosed with PH.

Dogs with moderate and severe PH showed an increase in the right ventricle (RV) size, which was suggestive of right sided congestive heart failure. Again, as in human medicine, the volume overload was confirmed to have more influence than pressure overload when analysing the right ventricle size.

The authors hypothesized that the severity of tricuspid regurgitation could play a more important role in the development of right sided congestive heart failure compared to the right ventricle systolic dysfunction. In fact, TR is the main determinant of RV enlargement in dogs with PH.

The right ventricular size in dogs was quantitatively assessed using the right ventricular end-diastolic area (RVEDA), a reliable index in, the authors’ opinion, which ensures complementary information in dogs with PH.

Vezzosi, T., et al. Echocardiographic evaluation of the right ventricular dimension and systolic function in dogs with pulmonary hypertension. Vet Intern Med. 2018;32:1541–1548: 10.1111/jvim.15253