Differential regulation of extracellular matrix constituents in myocardial remodeling with and without heart failure following pressure overload. Mus musculus

The aim of the present study was to examine potential differences in the regulation of myocardial ECM constituents, in mice that develop hypertrophy only (ABnonHF) and in mice that develop overt heart failure (ABHF) as response to pressure overload. Seven weeks old male C57BL/6 mice were subjected to aortic banding (AB) or sham operation (sAB), with sacrifice 4 weeks after banding. Prior to sacrifice, cardiac function and geometry were evaluated by echocardiography. Animals with comparable gradients over the banded ascending aorta, comparable cardiac output and heart rate were divided into two groups: ABnonHF and ABHF. Our criterion for dividing AB animals into these two groups was based on lung weight and left atrial diameter (LAD), as an increase in these parameters most likely is due to pulmonary congestion. Heart failure (HF) was defined as an increase in lung weight and LAD defining ABnonHF as lung weight/tibia length ≤ 10.5 mg/mm and LAD ≤ 2.0 mm and ABHF as lung weight/tibia length ≥ 15 mg/mm and LAD ≥ 2.4 mm. Overall design: Microarray screening was performed in 7 mice from each AB group and in 5 sAB mice. Sham was used as control.