The heart is located in the mediastinum underneath the sternum and is enclosed by a heart sac known as the pericardium which is built by two layers. The biggest part of the cardiac mass is built by the myocardium which is covered by the endocardium on the inside and by the epicardium on the outside of the haert.The heart itself consists of two ventricels and two atriums which are seperated from each other by cardiac valves and are connected to the pulmonary and systemic circulation.The heart gets its own blood supply by the coronary arteries. The cranial and dorsal parts of the heart where the big blood vessel trunks enter, are called basis cordis and the cardiac apex.
