title: Body weight loss after myocardial infarction in rats as a marker of early heart failure development.
abstract: OBJECTIVE
  We evaluated the use of body weight (BW) loss soon after acute myocardial infarction (MI) in rats as a marker of acute heart failure (HF).
  
  
  METHODS
  Female Wistar rats (200-240 g) were submitted either to sham operation or to coronary artery occlusion. In individual cages, daily BW and food and water intake were measured. Seven days later, cardiac function was evaluated by left ventricular catheterization. HF was defined by a left ventricular end-diastolic pressure greater than the upper limit of the 95% confidence interval. MI group was then divided into those that developed HF (n = 27; MI-HF) and those that did not (n = 47; MI).
  
  
  RESULTS
  The MI-HF group experienced increased BW loss (sham: 4.2 ± 0.6% MI: 0.4 ± 0.8%, MI-HF: -4.9 ± 1.2%; p <0.05) and reduced water and food intake compared with other groups. HF animals showed greater lung weight (sham: 1.460 ± 0.076 g, MI: 1.748 ± 0.086 g, MI-HF: 2.033 ± 0.13 g; p <0.05). Infarct area was significantly different between the groups (MI: 35.9 ± 0.9%, MI-HF: 39.7 ± 1.3%; p <0.05). ROC curve showed that BW loss over 7 days has 100% sensitivity and 72.3% specificity for identifying acute HF. Moreover, excluding the effect of infarct area on these results, a sample of animals with the same infarct area displayed similar morphometric and hemodynamic patterns as the entire sample. Multivariate linear regression analysis confirmed that BW loss is a HF marker independent of infarct area.
  
  
  CONCLUSIONS
  BW is an easy and reliable noninvasive method to detect HF early after MI in rats.
authors.affiliation: Department of Physiological Sciences, Federal University of Espirito Santo, Brazil. thais_oliveirafaria@hotmail.com
authors.forename: Thaís de Oliveira
authors.initials: Tde O
authors.lastname: Faria
authors.forename: Marcelo Perim
authors.initials: MP
authors.lastname: Baldo
authors.forename: Maylla Ronacher
authors.initials: MR
authors.lastname: Simões
authors.forename: Raquel Binda
authors.initials: RB
authors.lastname: Pereira
authors.forename: José Geraldo
authors.initials: JG
authors.lastname: Mill
authors.forename: Dalton Valentim
authors.initials: DV
authors.lastname: Vassallo
authors.forename: Ivanita
authors.initials: I
authors.lastname: Stefanon
mesh_terms: D000818:Animals; D015415:Biomarkers; D001835:Body Weight; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology*; D012372:ROC Curve; D051381:Rats; D017208:Rats, Wistar; D016277:Ventricular Function, Left / Q000502:physiology; D015431:Weight Loss
chemical_list: D015415:Biomarkers