Echocardiography in laboratory rabbits

Abstract

Introduction. Rabbits are used as convenient models for studying drug cardiotoxicity. Echocardiography is one of the most informative non-invasive methods of assessing the cardiovascular system function. In literature, there is no clearly formulated protocol for heart ultrasound examination in rabbits. Purpose was the systematization of literature data on echocardiography techniques in rabbits.Materials and methods. The sources search involved the Scientific Electronic Library eLIBRARY.RU and the National Library of Medicine information base (PubMed.gov). The search covered the 15-year period. Original or review articles containing a detailed description of the echocardiography technique were included.Results and discussion. For animals anesthesia before the study, various drugs combinations based on ketamine, xylazine, medetomidine, zolazepam, tiletamine are used. In rabbits, it is possible to use M-, B-, Doppler echocardiography modes in a wide frequency range (5 – 12 MHz). Parasternal longitudinal, parasternal transverse and apical ultrasound approaches are applied. The parameters of the transmitral blood flow (peak A, peak E, ratio A/E, peak E', the magnitude of regurgitation), as well as the contractile function of the left ventricle (end systolic and diastolic volumes and sizes, stroke volume, cardiac output, shortening fraction) are subject to assessment. The Teicholz and Simpson methods can be used to calculate the ejection fraction. The literature under survey coveres listed parameters of normal values for various ages’ rabbits.Conclusion. Echocardiography is a relatively affordable non-invasive method for studying the state of cardiovascular system in rabbits in an experiment. The method can be used to analyze myocardium size, left ventricle contractile function, and assess the state of heart valvular apparatus. At present, normal values of echocardiographic parameters in rabbits have been experimentally established, which adds to the informative value of the method. Qualitative study performance requires special preparation, including careful animal anesthesia, the choice of the approaches and modes used.