|Dog Cardiac Muscle 400X|
|Latin||textus muscularis striatus cardiacus|
Myocardium is the muscular tissue of the heart. Other tissues are the endocardium (inner lining, effectively a specialised endothelium) and the pericardium (a connective tissue layer around the heart). The myocardium is the middle layer of the walls of the heart, made of cardiac muscle, that contracts to push out blood.
The heart muscle can become sick and weak. Heart muscle can even die if blood flow stops. Most problems with the heart muscle come from defects in the blood supply. The regular contractions of the heart need an unending supply of oxygen from the arteries supplying the heart muscle.