You miss the point...zombie arnt mitological they do exist but there are simply different thatn Hollywood and books witch then to exagerate on any particular matter.They are here but are simply human with minimal phsicologial functions and istitutions thay lack logic and other moral skills...they dont eat brains and other body parts PERIOD.
And heart arest is very different from heart failure and heart atack.And missing limbs are strictly related to syfy and other Holywood and nonholywood productions.Please lets not mix books and movies with real life