Name the layers of the heart from the outside in.

The layers of the heart from the outer most to the innermost layer are: Epicardium, myocardium, endocardium.  The pericardium is actually the protective sac which surrounds the heart.  The heart is covered with a thin layer of slippery tissue called the epicardium, it provides a surface which can move inside the pericardium without causing friction.  The myocardium is the muscle tissue of the heart which conducts electricity which causes the muscle to squeeze pumping blood.  The endocardium is made of the same type of tissue as the epicardium. The endocardium is very smooth to prevent clots from forming and adhering to the valves.