The myocardium refers to which part of the heart?

The myocardium refers to which part of the heart?

• A. Thick middle layer made of muscle
• B. Smooth inner lining
• C. Outer protective layer
• D. Fatty tissue surrounding

Answer: (A)

The myocardium is the muscular middle layer of the heart wall that contracts to pump blood. It’s made of cardiac muscle fibers that generate force and are linked by intercalated discs to allow coordinated, synchronous beating. This layer lies between the inner lining (endocardium) and the outer covering (epicardium) of the heart. The epicardium is part of the heart’s protective outer layers, while fat surrounding the heart is adipose tissue and not the muscle layer. The myocardium is thicker in the ventricles—especially the left ventricle—because it needs to produce the higher pressures required to push blood into the systemic circulation.

The myocardium is the muscular middle layer of the heart wall that contracts to pump blood. It’s made of cardiac muscle fibers that generate force and are linked by intercalated discs to allow coordinated, synchronous beating. This layer lies between the inner lining (endocardium) and the outer covering (epicardium) of the heart. The epicardium is part of the heart’s protective outer layers, while fat surrounding the heart is adipose tissue and not the muscle layer. The myocardium is thicker in the ventricles—especially the left ventricle—because it needs to produce the higher pressures required to push blood into the systemic circulation.