Effect of Single-dose Pimobendan on Echocardiographic Parameters in Healthy New Zealand White Rabbits

Document Type : Research Article


1 Department of Veterinary Clinical Sciences, Karaj branch, Islamic Azad University, Karaj, Iran.

2 Department of Pharmacology, Karaj branch, Islamic Azad University, Karaj, Iran.

3 Department of Radiology, Karaj branch, Islamic Azad University, Karaj, Iran.

4 Department of Surgery and Radiology, Faculty of veterinary medicine, University of Tehran, Tehran, Iran.


keeping rabbits as pets and their use in laboratory research increased the need for studying heart diseases and treatments in rabbits. Pimobendan is one of the most common medications used in cardiac diseases and is anecdotal in rabbits. The first step toward the approval of pimobendan in rabbits is assessing the potential for beneficial effects on cardiac function through echocardiographic functional parameters.This study aimed to determine the effects of pimobendan on echocardiographic parameters. Eleven rabbits were included in this study. Echocardiographic examinations were performed before and after pimobendan administration for each rabbit. The LV morphological and functional parameters were compared between study time points. Pimobendan resulted in changes in several echocardiographic variables in the rabbits, including FS and an increase in EF, SV, LVPWs, and LA end-systolic (p = 0.0001, p = 0.0001, p = 0.0284, p = 0.0272, and p = 0.0007, respectively). Moreover, LVIDs and end-systolic volume decreased (p = 0.0343 and p = 0.038). The changes in some parameters were not significant, such as LVIDd, LVPWd, end-diastolic volume, LA max,  Mitral annulus diameter, and LA/Ao. FS, which indicates an increase in the power of heart contraction and consequently an improvement in heart function, increased in this study after pimobendan administration. Therefore, it can be concluded that pimobendan improves cardiac functions. Further studies are required to investigate whether pimobendan has similar effects in rabbits with cardiac diseases. 


Main Subjects

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