The Effect of Pimobendan on Left Atrial Pressure in Dogs with Mitral Valve Regurgitation

Abstract

Background: The effects of pimobendan on left atrial pressure (LAP) in dogs with mitral valve disease (MR) have not been documented in a quantitative manner. Objective: The objective was to document and study the short-term effects of pimobendan on LAP and echocardiographic parameters in MR dogs. Animals: Eight healthy Beagle dogs weighing 10.0-14.7 kg (3 males and 5 females; aged 2 years) were used. Methods: Experimental, cross-over, and interventional study. Dogs with surgically induced MR received pimobendan at either 0.25 mg/kg or 0.50 mg/kg PO q12h for 7 days and then, after a 7-day wash-out period, the other dosage. LAP was measured for 30 minutes at baseline and again on days 1, 2, 4, and 7 of pimobendan administration. Results: Mean LAP was significantly decreased after the administration of 0.25 mg/kg (15.81 ± 5.44 mmHg to 12.67 ± 5.71 mmHg, P