  In this work, we investigated the effect of varying strength of Hyperkalemia
and Hypoxia, in human cardiac tissue with a local ischemic subregion, on the
electrical and mechanical activity of healthy and ischemic zones of the cardiac
muscle. The Monodomain model in a deforming domain is taken with the addition
of mechanical feedback and stretch-activated channel current coupled with the
ten Tusscher human ventricular membrane model. The equations of finite
elasticity are used to describe the deformation of the cardiac tissue. The
resulting coupled electro-mechanical PDEs-ODEs non-linear system is solved
numerically using finite elements in space and finite difference method in
time. We examined the effect of local ischemia on cardiac electrical and
mechanical activity in different cases. We concluded that the spread of
Hyperkalemic or Hypoxic region alters the electro-mechanical coupling in terms
of the action potential ($v$), intracellular calcium ion concentration
$[Ca^{+2}]_i$, active tension, ($T_A$), stretch ($\lambda$), stretch rate ($
\frac{d \lambda}{dt}$). With the increase in the size of the ischemic region by
a factor of five, approximately $45\%$ variation in the stretch rate $\frac{d
\lambda}{dt}$ is noticed. It is also shown that ischemia affects the
deformation (expansion and contraction) of the heart.
