What is the outer membrane that encloses the heart called?

The outer membrane that encloses the heart is known as the pericardium. This structure is a double-walled sac that serves multiple important functions. It provides a protective layer around the heart, preventing it from infection and allowing for smooth movement as the heart beats. The pericardium also helps to anchor the heart in place within the thoracic cavity while allowing for some degree of flexibility.

The pericardium consists of an outer fibrous layer and an inner serous layer, which itself is divided into two parts: the parietal layer lining the fibrous layer and the visceral layer, also known as the epicardium, which directly covers the heart. This distinction is crucial in understanding the anatomy of the heart and its surrounding structures.

In contrast, the myocardium refers to the muscular layer of the heart that is responsible for pumping blood, and the endocardium is the inner lining of the heart, which lines the heart chambers and covers the heart valves. The epicardium, while sometimes considered part of the pericardium, specifically refers to the visceral layer that adheres to the surface of the heart. Hence, the term pericardium accurately describes the protective outer membrane that encloses the entire heart