Premium
Ventricular repolarization in a rat model of global heart failure
Author(s) -
Krandycheva Valeria,
Kharin Sergey,
Strelkova Marina,
Shumikhin Konstantin,
Sobolev Aleksey,
Shmakov Dmitry
Publication year - 2013
Publication title -
clinical and experimental pharmacology and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 103
eISSN - 1440-1681
pISSN - 0305-1870
DOI - 10.1111/1440-1681.12104
Subject(s) - cardiology , repolarization , heart failure , medicine , ventricular repolarization , myocardial infarction , hemodynamics , electrophysiology
Summary Isoproterenol in high doses induces infarction‐like myocardial damage and structural and functional remodelling of the ventricular myocardium. The purpose of the present study was to investigate ventricular repolarization in a rat model of isoproterenol‐induced heart failure. Isoproterenol was administered twice to female W istar rats (170 mg/kg, s.c., 24 h apart). Four weeks after the injections, cardiac output was measured and unipolar epicardial ventricular electrograms were recorded in situ . Activation–recovery intervals were calculated to assess repolarization. Histological examination of the heart ventricles was also performed. Heart failure in rats treated with isoproterenol was indicated by myocardial histopathological damage and reduced cardiac output. In rats with heart failure, the regional differences in activation–recovery interval prolongation over the ventricular epicardium resulted in increasing heterogeneity in the activation–recovery interval distribution and increasing repolarization heterogeneity of the ventricular subepicardium. Myocardial damage and haemodynamic changes in heart failure induced by isoproterenol were accompanied by significant changes in ventricular repolarization, which were not associated with myocardial hypertrophy.