Body weight loss as an independent marker of acute heart failure after myocardial infarction in rats

This work evaluates the body weight (BW) loss after acute myocardial infarction in rats as a marker of acute heart failure (HF). Female Wistar rats (200–240 g) were divided in fictitious surgery (SHAM) or submitted to coronary artery occlusion (MI). In individual cages, BW, food and water intake were measured daily. Seven days later, cardiac function was evaluated and than, MI group was subdivided (based in the superior limit of CI95% to the LVEDP) in those developed (n=27; MI‐HF) or not (n=47; MI) acute heart failure. MI‐HF group depicted higher BW loss (SHAM: 4.2±0.6; MI: 0.4±0.8; MI‐HF: −4.9±1.2 g; P <0,05) and reduced water and food intake as compared with other groups. The infarct size was different between the groups MI (MI:35.9±0.9; MI‐HF: 39.7±1.3%; P <0,05). The ROC curve showed that seven days BW loss has 100% sensibility and 72.3% specificity to identify acute HF, different from other classical predictors (infarct size, lung and right ventricle). Moreover, to exclude the infarct size interference, a sample of animals with the same infarct size followed the same patterns found previously. Multivariate regression analysis confirmed that BW loss as an independent marker for acute HF development. Thus, seven days after MI is possible divide animals with or without HF through BW changes. Supported by CNPq and CAPES.