title: Electrocardiograms corresponding to the development of myocardial infarction in anesthetized WHHLMI rabbits (Oryctolagus cuniculus), an animal model for familial hypercholesterolemia.
abstract: The aim of this study was to determine whether features indicative of myocardial ischemia occur in the electrocardiograms (ECG) in myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbits, an animal model for human familial hypercholesterolemia. ECG were recorded  in 110 anesthetized WHHLMI rabbits (age, 10 to 39 mo) by using unipolar and bipolar limb leads with or without chest leads. We noted the following electrocardiographic changes: T wave inversion (37.4%), ST segment depression (31.8%), deep Q wave (16.3%), reduced R wave amplitude (7.3%), ST  segment elevation (2.7%), and high T wave (1.8%). These ECG changes resembled those in human patients with coronary heart disease. Histopathologic examination revealed that the left ventricular wall showed acute myocardial lesions, including loss of cross-striations, vacuolar degeneration,  coagulation necrosis of cardiac myocytes, and edema between myofibrils, in addition to chronic myocardial lesions such as myocardial fibrosis. The coronary arteries that caused these ECG changes were severely stenosed due to atherosclerotic lesions. Ischemic ECG changes corresponded to the  locations of the myocardial lesions. Normal ECG waveforms were similar between WHHLMI rabbits and humans, in contrast to the large differences between rabbits and mice or rats. In conclusion, ischemic ECG changes in WHHLMI rabbits reflect the location of myocardial lesions, making this model  useful for studying coronary heart disease.
authors.affiliation: Institute for Experimental Animals, Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan. tsutomu.kobayashi.jap@gmail.com
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Ito
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamada
authors.forename: Nobue
authors.initials: N
authors.lastname: Kuniyoshi
authors.forename: Masashi
authors.initials: M
authors.lastname: Shiomi
mesh_terms: D000818:Animals; D003331:Coronary Vessels / Q000473:pathology; D004195:Disease Models, Animal; D004562:Electrocardiography / Q000379:methods*; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000150:complications*; D051379:Mice; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000209:etiology* / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000473:pathology; D009336:Necrosis; D011817:Rabbits; D051381:Rats; D018709:Statistics, Nonparametric