Which layer of the heart is responsible for its contraction?

The myocardium is the layer of the heart responsible for its contraction. It consists of specialized cardiac muscle tissue that allows the heart to pump blood throughout the body. This muscular layer is thickest in the walls of the ventricles, where the force needed for pumping blood to the lungs and the rest of the body is greatest. Unlike the other layers, such as the endocardium (the inner lining), the epicardium (the outer layer), and the pericardium (a protective sac surrounding the heart), the myocardium is specifically designed to contract and generate the mechanical force required for circulation. The coordinated contractions of the myocardium are essential for maintaining an effective heartbeat and overall cardiovascular function.