Describe the structure of the pericardium and the layers of the wall of the heart.
orchid101 | Student
The wall of the heart in the adult is divided into three layers known as the endocardium, myocardium and epicardium, The endocardium consists of the endothelium which is continuous with that of blood vessels and of subendothelial connective tissue. The myocardium is the muscle layer upon which depends the pumping action of the heart. It is thin in the auricles but very thick in the ventricles. In the left ventricle, which pumps blood into the farthest parts of the body, it is much thicker than in the right. The epicardium consists of the pericardial mesothelium together with underlying connective tissue. This layer is also called the visceral pericardium and with the parietal pericardium it bounds the pericardial cavity, forming a closed sac containing the pericardial fluid.