Acute and Chronic Animal Models of Cardiac Arrhythmias

Abstract

Animal models have played a major role in the development of new antiarrhythmic drugs as well as contributed to our understanding of the mechanisms of antiarrhythmic drug action. The number and diversity of experimental animal models used to screen and evaluate potential antiarrhythmic agents points out the inadequacy of any one model to reproduce the malignant arrhythmias which occur in man. An ideal animal model would both closely simulate a human counterpart and permit control of most variables. “All animal models are wrong, but some are useful” because by selecting the appropriate animal model valuable information can be obtained. Most animal models are nonatherogenic, nonprimate, and arrhythmias occur in ischemic or infarcted hearts with otherwise normal coronary anatomy. In animals drug dosages and metabolites differ from those in humans and concomitant pulmonary, renal and hepatic disease is not present. In spite of their limitations, animal models still have to be used to develop and evaluate pharmacological, surgical and electrical pacing techniques for controlling and preventing malignant arrhythmias.