All Phenotypes Tg(Myh6-MYL3*A57G)#Dsc MGI Mouse

abnormal cardiac muscle tissue morphology ( J:178377 )

• papillary muscle fibers show a change in the interfilament spacing in rigor, with the lattice spacing being reduced in the myocardium

• however, no alterations in actomyosin cross-bridge mass distribution are seen

increased myocardial fiber size ( J:202154 )

• increase in size of cardiomyocytes

increased heart weight ( J:202154 )

• heart-to-body weight ratio is increased

cardiac hypertrophy ( J:202154 )

• decrease in number of nuclei indicating cardiac hypertrophy

• left ventricular volumes in diastole and systole are larger, indicating development of eccentric hypertrophy

abnormal heart left ventricle morphology ( J:178377 )

• left ventricle exhibits myofilament disarray and signs of fibrosis

cardiac interstitial fibrosis ( J:178377 , J:202154 )

• left ventricle exhibits signs of fibrosis (J:178377)

• however, hearts exhibit normal size in 10-12 month old males (J:178377)

• hearts exhibit severe fibrosis as early as 6 months of age (J:202154)

abnormal cardiovascular system physiology ( J:202154 )

• during inferior vena cava occlusion, the load-independent end-systolic elastance is higher compare to controls

abnormal blood circulation ( J:202154 )

• stroke work is increased

increased cardiac output ( J:202154 )

increased cardiac stroke volume ( J:202154 )

increased heart left ventricle muscle contractility ( J:202154 )

• increase in left ventricular end diastolic volume with higher left ventricular end systolic pressure, indicating higher heart contractility

abnormal heart echocardiography feature ( J:202154 )

• echocardiography shows larger left ventricular volumes in diastole and systole, however left ventricle posterior wall and anterior wall dimensions are normal

increased left ventricle systolic pressure ( J:202154 )

• higher left ventricular end systolic pressure

abnormal myocardial fiber physiology ( J:178377 , J:202154 )

• muscle fibers exhibit increased stiffness (J:178377)

• skinned papillary muscle show a 20-35% decrease in maximal tension (J:202154)

• papillary muscle shows a small, but significant, increase in the calcium sensitivity of force (J:202154)

• level of passive tension is increased in skinned papillary muscle, suggesting higher stiffness (increased resistance to stretch) in the myocardium (J:202154)