View of the vental surface of the heart. You can identify the front of the heart by locating the interventricular sulcus and the large pulmonary artery. The flaps on the front that cover the two atria are called the auricles. The pulmonary artery is the most anterior of the vessels and has thin walls.


The blue pencil is in the aorta, which is situated behind the pulmonary artery. It has much thicker walls and has a branch, the brachiocephalic, indicated by the red pencil.