Experimental Study About Choosing The Views And Index Of Transthoracic Echocardiography In Commonly Used Experimental Animals

Objective: This study sought to find the most robust standard two-dimensional viewsand index of transthoracic echocardiography by assessing the agreement and reliability inthe commonly used experimental animals (pigs, rabbits and rats).Methods: The study object consisted of normal pigs (n=19), normal rabbits (n=8) andrats (n=13). Transthoracic echocardiography measurements were evaluated for thefollowing:(1) to determine feasibility of the three standard two-dimensional views bycalculating agreement of its acquired conditions using Cohen’s kappa;(2) to determinefeasibility and repeatability of M mode quantitative parameters, FAC (fractional areachange) and Simpson method;(3) to pick out index reflecting cardiac diastolic function insmall experimental animals (rats);(4) to evaluate the effect of thoracotomy by analyzingthe views and index before and after myocardial infarction model; and (5) to explorefeasibility of two-dimensional speckle tracking in rabbits and rats.Results:(1) PSSAX(The parasternal long axis view) and PSLAX(The parasternallong axis view) were better than apical four chamber view, which was nonstandard, lowacquired and poor repeatability. The acquired rate of views in rats after thoracotomydecreased slightly, but the difference was not significant;(2) The repeatability of M modemeasurements were excellent for both intraobserver and interobserver, and PSLAXparameters had better reliable than those obtained in PSLAX;(3) The repeatability of FACwas excellent in all subjects, EF（ejection fraction） was significantly lower by Simpsonmethod than others, and its repeatability was poor;(4) Vp had better repeatability than thespectrum of mitral valve flow and tissue Doppler of mitral annular, which were difficult toobtain or analyze in rats; and (5) speckle tracking parameters in PSSAX was excellent inrats and rabbits, but repeatability of longitudinal strain index was common in rabbits. Conclusion:(1) PSSAX and PSLAX were preferred in experimental animals likepigs, rabbits and rats; FAC was the most reliable indicator for left ventricular systolicfunction; M mode measurement can continue to use in normal state; Simpson method forleft ventricular function was not recommended;(2) we can use speckle tracking method inparasternal short axis view to study myocardiac mechanics in rabbits and rats; and (3) wecan evaluate left ventricular diastolic function using Vp indicators in rats. The spectrum ofmitral valve flow and tissue Doppler of mitral annular were not recommended.