Heart test results in dogs with precapillary lung high blood pressure

Abstract

INTRODUCTION/OBJECTIVES: This study evaluated circulating amino-terminal pro-B-type natriuretic peptide (NT-proBNP), amino-terminal pro-A-type natriuretic peptide (NT-proANP), and cardiac troponin I (cTnI) concentrations in dogs with precapillary pulmonary hypertension (Pre-PH) and control dogs with respiratory clinical signs but no Pre-PH. ANIMALS: Twenty-six dogs (17 affected, and nine controls) were involved in the study. MATERIALS AND METHODS: This was a sub-study of a large prospective single-center observational study. Dogs underwent blood sample collection, physical examination, and echocardiographic evaluation. Precapillary pulmonary hypertension was diagnosed when a calculated right ventricular-to-right atrial pressure gradient (RV:RA PG) measuring ≥40 mmHg was identified echocardiographically, barring right ventricular outflow obstruction and/or left-sided cardiac disease. RESULTS: Two, nine, and six dogs had mild, moderate, and severe Pre-PH, respectively. Plasma concentrations of NT-proBNP, NT-proANP, and cTnI were significantly higher in the affected group than in the control group (P=0.020, P=0.009, P=0.011, respectively). There was a positive correlation between RV:RA PG and NT-proBNP (r = 0.52), NT-proANP (r = 0.54), and cTnI (r = 0.67) concentrations. DISCUSSION: Precapillary pulmonary hypertension should be included in the differential diagnosis list of elevated cardiac biomarker concentrations in dogs with respiratory signs. STUDY LIMITATIONS: Strict selection criteria reduced group sizes. There were rare missing data points. The diagnosis of Pre-PH was obtained from Doppler echocardiographic RV:RA PG. The disease process causing Pre-PH was not evaluated histopathologically. CONCLUSIONS: Circulating cardiac biomarker concentrations are increased in dogs with Pre-PH and there is a positive correlation between RV:RA PG and NT-proBNP, NT-proANP, and cTnI concentrations.