Sheeza Basharatabout 5 hours ago

Heart Wall

The heart wall consists of three layers: the outer epicardium, the muscular middle layer called the myocardium, and the inner endocardium. The epicardium is the heart's protective outer layer that also helps reduce friction, the myocardium is the thickest layer responsible for the heart's forceful contractions to pump blood, and the endocardium is a smooth, thin lining that protects the heart's internal surfaces and valves.