Abstract
BACKGROUND: Cardiovascular diseases with increased right ventricular (RV) afterload induce RV diastolic and systolic dysfunction, and myocardial fibrosis in humans. Studies in dogs with pulmonary stenosis (PS) evaluating RV diastolic function and markers of myocardial fibrosis are lacking. HYPOTHESIS/OBJECTIVES: Dogs with PS have echocardiographic evidence of RV diastolic and systolic dysfunction and increased serum concentrations of galectin-3 (Gal-3), a surrogate biomarker for myocardial fibrosis. ANIMALS: Forty client-owned dogs (10 controls, 30 with PS). METHODS: Prospective study. All dogs had systemic blood pressure measurement, serum biochemical analysis, echocardiography, and measurement of serum Gal-3 concentration performed. RESULTS: Variables of RV diastolic function were obtained in 39/40 dogs. Trans-tricuspid flow velocity in early diastole to trans-tricuspid flow velocity in late diastole ratios (RV E/A) were lower (P < .001) in dogs with PS (median, 0.94; range, 0.62-2.04) compared to controls (1.78; 1.17-2.35). Trans-tricuspid flow velocity in early diastole to tricuspid annular myocardial velocity in early diastole ratios (RV E/e') were higher (P < .001) in dogs with PS (11.55; 4.69-28) compared to control (6.21; 5.16-7.21). Variables of RV systolic function were lower in dogs with PS (P = <.001). Serum Gal-3 concentration was higher (P = .002) in dogs with PS (285.1 pg/mL; 94.71-406.97) compared to control dogs (162.83 pg/mL; 52.3-232.82). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with PS have RV diastolic and systolic dysfunction, and increased Gal-3 concentrations. These findings suggest the presence of RV myocardial fibrosis in dogs with PS, which could impact clinical management.