Myocardium
Myocardium is the muscular middle layer of the wall of the
heart. It is composed of spontaneously contracting cardiac
muscle fibers which allow the heart to contract. Heart contraction is an autonomic (involuntary) function of the
peripheral nervous system. The myocardium is surrounded by the
epicardium (outer layer of the wall of the heart) and the
endocardium (inner layer of the heart).
Function of the Myocardium
Myocardium stimulates heart contractions to pump blood from the
ventricles and relaxes the heart to allow the
atria to receive blood. These contractions produce what is known as a heart beat. The beating of the heart drives the
cardiac cycle which pumps blood to
cells and
tissues of the body.
