title: Relative role of left ventricular geometric remodeling and of morphological and functional myocardial remodeling in the transition from compensated hypertrophy to heart failure in rats with supravalvar aortic stenosis.
abstract: OBJECTIVE
  To evaluate the relative contribution of left ventricular (LV) geometric remodeling and of morphological and functional myocardial changes in rats with induced supravalvar aortic stenosis (SAS), in the transition from compensated hypertrophy to congestive heart failure (CHF).
  
  
  METHODS
  Twenty one weeks after induction of SAS, the rats were classified as controls (CG, n=13), without congestive heart failure (SG, n=11), or with congestive heart failure (SG-HF, n=12). All groups were evaluated with echocardiographic, hemodynamic and morphological study of the myocardium.
  
  
  RESULTS
  Twenty one weeks after SAS: mass index (SG-HF>SG>CG, p<0.05); systolic pressure (SG-HF= SG>CG, p<0.05); diastolic pressure (SG-HF>SG>CG, p<0.05); systolic and diastolic meridional stress (SG-HF>SG>CG, p<0.05); LV myocyte cross-sectional area (SG-HF>SG>CG, p<0.05) and hydroxyproline content (SG-HF>SG>CG, p<0.05). In the SG-HF group, LV geometric remodeling was characterized by a significant increase in dimensions and relative thickness of the normal wall (excentric remodeling), whereas the SG group presented a concentric remodeling. Indexes of LV performance in the SG-HF group were significantly lower than those of the SG group.
  
  
  CONCLUSIONS
  The SG-HF and SG groups differed primarily in the LV geometric remodeling and structural myocardial remodeling process, which established a chronically compensated state in the SG group and triggered CHF in the SG-HF group in the presence of equivalent degrees of impaired contractility.
authors: Faculdade de Medicina de Botucatu, Universidade Estadual de São Paulo, Brazil. bregagnollogh@ig.com.br
authors: Edson Antonio
authors: EA
authors: Bregagnollo
authors: Marco Aurélio
authors: MA
authors: Mestrinel
authors: Katashi
authors: K
authors: Okoshi
authors: Fábio Cardoso
authors: FC
authors: Carvalho
authors: Isamara Fernanda
authors: IF
authors: Bregagnollo
authors: Carlos Roberto
authors: CR
authors: Padovani
authors: Antonio Carlos
authors: AC
authors: Cicogna
mesh_terms: D000818:Animals; D021921:Aortic Stenosis, Supravalvular / Q000150:complications / Q000503:physiopathology*; D004195:Disease Models, Animal; D004452:Echocardiography; D006333:Heart Failure / Q000209:etiology / Q000503:physiopathology*; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D020257:Ventricular Remodeling / Q000502:physiology*