Hyperthyroid cats have altered pulmonary arterial hemodynamics but rarely have intermediate or high probability of pulmonary hypertension.

Abstract

OBJECTIVE: Apply the 3-site echocardiographic metrics utilized to assess pulmonary hypertension (PH) probability in dogs and humans to feline echocardiographic examinations to investigate the translatability of this scheme and subsequent enhancement of detection of PH in cats. ANIMALS: 27 client-owned cats (euthyroid [n = 11] and hyperthyroid [16]). METHODS: This was a single-center, prospective, observational case-control study. Demographic, physical examination, and echocardiographic data from hyperthyroid and euthyroid cats were compared via Fisher exact test and Kruskal-Wallis test. RESULTS: Hyperthyroid versus euthyroid cats had significantly greater right atrial area index values and were more likely to have late-peaking main pulmonary artery pulsed-wave flow profiles. Two hyperthyroid cats had measurable tricuspid regurgitation tracings (one with a high probability of PH and another with a low probability of PH). CLINICAL RELEVANCE: Hyperthyroid cats demonstrated altered pulmonary arterial hemodynamics and lacked consistent intermediate or high probability of PH. The 3-site echocardiographic metrics scheme is applicable for the evaluation of right-sided cardiac and pulmonary arterial hemodynamics in cats. Further research is needed to determine reference ranges in larger populations of healthy cats and those with high clinical suspicion for PH.