Cardiac functional analysis in the progenies obtained from cross-breeding between K51R-Tg and Nkx2.5+/− mouse lines.

Echocardiography was performed on animals of 4 months age as described in Materials and Methods. Note that although there was no statistically significant difference reached in all parameters shown between compound K51R-Tg/Nkx2.5+/− group and the other three groups due to small size of the sample examined, there was a trend of increase in diastolic and systolic volumes, and a trend of decrease in cardiac function (%EF and %FS) in the compound K51R-Tg/Nkx2.5+/− mice compared with the other group animals. EF, ejection fraction; FS, fractional shortening.