What is the myocardium?

The myocardium is defined as the middle layer of the heart muscle and is primarily responsible for the heart’s pumping action. This layer is composed of specialized cardiac muscle tissue that contracts rhythmically, enabling the heart to pump blood throughout the body. The myocardium is crucial for maintaining the heart's functionality, as it provides the force needed to circulate blood to the lungs and the rest of the body's tissues.

In contrast, the other layers and components of the heart serve different roles. The outer layer, or epicardium, provides protection and reduces friction as the heart beats. The inner lining, known as the endocardium, lines the chambers of the heart and helps regulate blood flow. The valve structures within the heart play a role in directing blood flow and preventing backflow, but they do not contribute to the heart's pumping mechanism. Understanding the specific functions of each layer and component of the heart highlights the importance of the myocardium in the overall cardiovascular system.