The main muscle of the heart is the myocardium.
The heart wall is composed of three layers: the epicardium (outer layer), the myocardium (middle layer), and the endocardium (inner layer). The myocardium is the thickest and most substantial of these layers, consisting primarily of cardiac muscle tissue. It is responsible for the heart's ability to contract and pump blood throughout the body.
- Epicardium: The thin, outer layer that protects the heart.
- Myocardium: The muscular middle layer responsible for contraction.
- Endocardium: The thin, inner layer that lines the heart chambers.
The myocardium's structure is uniquely adapted for its function. Cardiac muscle cells are interconnected by intercalated discs, which allow for rapid and coordinated spread of electrical impulses, enabling the heart to contract as a single unit. This coordinated contraction is essential for effective blood pumping. Damage to the myocardium, such as in a heart attack (myocardial infarction), can severely impair the heart's function.
