Chest · Cardiac muscle
Heart Muscle (Cardiac Muscle)
Cardiac muscle is the special muscle that makes up the heart wall. Unlike other muscles, it never tires and contracts automatically, beating around the clock for a lifetime.
What it is
Cardiac muscle (myocardium) is a unique type of muscle found only in the heart, whose cells are joined so they contract together in a coordinated wave.
Where it is
The walls of the heart, in the chest.
What it does
Contracts rhythmically to pump blood around the body, driven by the heart's own electrical system.
Everyday use
Every heartbeat — around 100,000 a day — is a contraction of cardiac muscle, working continuously without conscious effort.
When things go wrong
Common problems affecting the heart muscle (cardiac muscle)
- Heart attack (damage to heart muscle from blocked blood supply)
- Cardiomyopathy (disease of the heart muscle)
- Heart failure
Education and reference only. This explains the anatomy in plain terms and is not a diagnosis. Sudden severe symptoms — such as crushing chest pain or collapse — are an emergency; call 999.
Looking after it
Keeping it healthy
The same habits that protect the heart — not smoking, exercise, a healthy diet, and controlling blood pressure and cholesterol — protect the heart muscle.
Did you know?
An interesting fact
Cardiac muscle is the only muscle that contracts entirely on its own, generating its own electrical rhythm without any signal from the brain.
Answers
Heart Muscle (Cardiac Muscle): frequently asked questions
How is heart muscle different from other muscle?
Cardiac muscle contracts automatically and rhythmically without tiring, driven by the heart's own electrical system — unlike the skeletal muscles you move at will.
What happens to heart muscle in a heart attack?
A heart attack occurs when the blood supply to part of the heart muscle is blocked, so that area is starved of oxygen and can be damaged. It is an emergency — call 999.
Related muscles
Explore the chest
Sources
Where this is drawn from
- NHS — Muscles and movement
- Gray's Anatomy for Students
- TeachMeAnatomy — muscular system
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