Electrocardiograms Corresponding to the Development of Myocardial Infarction in Anesthetized WHHLMI Rabbits (Oryctolagus cuniculus), an Animal Model for Familial Hypercholesterolemia

摘要

Theaimofthisstudywastodeterminewhetherfeaturesindicativeofmyocardialischemiaoccurintheelectrocardiograms(ECG)inmyocardialinfarction-proneWatanabeheritablehyperlipidemic(WHHLMI)rabbits,ananimalmodelforhumanfamilialhypercholesterolemia.ECGwererecordedin110anesthetizedWHHLMIrabbits(age,10to39mo)byusingunipolarandbipolarlimbleadswithorwithoutchestleads.Wenotedthefollowingelectrocardiographicchanges:Twaveinversion(37.4%),STsegmentdepression(31.8%),deepQwave(16.3%),reducedRwaveamplitude(7.3%),STsegmentelevation(2.7%),andhighTwave(1.8%).TheseECGchangesresembledthoseinhumanpatientswithcoronaryheartdisease.Histopathologicexaminationrevealedthattheleftventricularwallshowedacutemyocardiallesions,includinglossofcross-striations,vacuolardegeneration,coagulationnecrosisofcardiacmyocytes,andedemabetweenmyofibrils,inadditiontochronicmyocardiallesionssuchasmyocardialfibrosis.ThecoronaryarteriesthatcausedtheseECGchangeswereseverelystenosedduetoatheroscleroticlesions.IschemicECGchangescorrespondedtothelocationsofthemyocardiallesions.NormalECGwaveformsweresimilarbetweenWHHLMIrabbitsandhumans,incontrasttothelargedifferencesbetweenrabbitsandmiceorrats.Inconclusion,ischemicECGchangesinWHHLMIrabbitsreflectthelocationofmyocardiallesions,makingthismodelusefulforstudyingcoronaryheartdisease.