What is the function of the epicardium in the heart?

The epicardium serves as the outer layer of the heart wall. This layer is also known as the visceral layer of the pericardium, which is a double-walled sac that encloses the heart. The primary function of the epicardium is to provide a protective covering for the heart and to house the coronary blood vessels that supply the heart tissue with oxygen and nutrients. Additionally, it plays a role in reducing friction between the heart and the surrounding structures as the heart expands and contracts during its beating cycle. Its positioning as the outermost layer is crucial for the overall integrity and function of the heart.