Myocardium
The heart is a muscular organ comprised of three layers that include the endocardium, myocardium, and epicardium.
The myocardium is the middle muscular layer of the heart. It is the thickest layer which lies between the single-cell endocardium layer, and the outer epicardium, which makes up the visceral pericardium that surrounds and protects the heart. The myocardium is composed of specialized muscle cells called cardiomyocytes. These cells have unique cellular features that correlate to their contractile function. One distinct feature present only in cardiomyocytes are intercalated discs which contain gap junctions (adhesions that facilitate fast cell to cell communication). Due to these features, the myocardium functions as a syncytium with synchronized contraction.
The main function of the myocardium is to facilitate the contraction and relaxation of the heart walls in order to receive and pump the blood into the systemic circulation. In addition, the myocardial cells provide a scaffold for heart chambers and conduct electrical stimuli.
Terminology |
English: Myocardium English synonyms: Cardiac muscle, Cardiac striated muscle Latin: Myocardium Latin synonyms: Textus muscularis cardiacus, Textus muscularis striatus cardiacus |
Definition | Middle muscular layer of the heart |
Function |
Contraction of the heart; Conduction of electrical stimuli; Provides a scaffold for heart chambers |
Learn everything about the structures of the heart with the following study unit:
Myocardium: want to learn more about it?
Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster.
What do you prefer to learn with?
“I would honestly say that Kenhub cut my study time in half.”
–
Read more.