Forms Combining of the Cardiovascular System Angi(o)/ vas(o)/ vascul(o) Vessel aort(o) Aorta arteri(o) Artery ather(o) Fatty (lipid) paste atri(o) Atrium cardi(o) Heart coron(o) Circle or crown my(o) Muscle pector(o)/ steth(o) Chest sphygm(o) Pulse thromb(o) Clot ven(o)/ phleb(o) Vein varic(o) Swollen, twisted vein ventricul(o) Ventricle (belly or pouch) Anatomical Terms Atrium Upper right or left chamber of the heart Endocardium Membrane lining the cavities of the heart Epicardium Membrane forming the outer layer of the heart Interatrial septum Partition between right and left atrium Interventricular septum Partition between right and left ventricle Myocardium Heart muscle Pericardium Protective sac enclosing the heart composed of two layers with fluid between Ventricle Lower right or left chamber of the heart Valves of Heart and Veins Heart valves Structures within the heart that open and close with the heartbeat to regulate the one-way flow of the blood Aortic valve Heart valve between the left ventricle and the aorta Mitral or bicuspid valve Heart valve between left the atrium and the left ventricle Pulmonary semilunar valve Heart valve opening from the right ventricle to the pulmonary artery Tricuspid valve Valve between the right atrium and the right ventricle Valves of the veins Valves located at intervals within the lining of veins, especially in the legs, which constrict with muscle action to move the blood returning to the heart Blood Vessels Arteries Vessels that carry blood from the heart to arterioles Aorta Large artery that is the main trunk of the arterial system branching from the left ventricle Arterioles Small vessels that receive blood from the arteries Capillaries Tiny vessels that join arterioles and venules Venules Small vessels that gather blood from the capillaries into the veins Veins Vessels that carry blood to the heart from the venules Circulation Systemic circulation Circulation of blood throughout the body through arteries, arterioles, capillaries, venules, and veins to deliver oxygen and nutrients to body tissues Coronary circulation Circulation of blood through the coronary blood vessels