this, it beats an average of 60 to 100 times a minute for your entire lifetime. Your heart is located in the center of your chest, slightly to the left, in an area called the mediastinum. It has three layers: the outer lining, called the epicardium; the middle muscular layer, called the myocardium; and the inner lining, called the endocardium. The heart is enclosed in a fibrous membrane called the pericardium, or pericardial sac, which also contains a small amount of pericardial fluid.

The tricuspid valve exits the right atrium into the right ventricle, and the mitral, or bicuspid valve, exits the left atrium into the left ventricle. The pulmonary valve exits the right ventricle into the pulmonary arteries, and the aortic valve exits the left ventricle into the aorta.

The largest part of the heart, the lower left area, is known as the apex. This site is best for auscultating (listening to) sounds from the mitral valve and is where the apical pulse is best heard.

The pulmonary veins are unique in that they are the only veins in the body that transport oxygen-rich blood.

arteriosclerosis develops in these vessels; in this condition, the vessels become narrowed and hardened due to a number of factors, including hypertension (high blood pressure). In addition, a fatty, plaque-like substance composed of cholesterol may build up on the inside surfaces of the coronary vessels, causing further narrowing or even blockage

his is known as atherosclerosis and contributes to the development of coronary artery disease (CAD). It is also sometimes called atherosclerotic heart disease (ASHD).

myocardial infarction (MI) or a heart attack.

A cluster of specialized cells in your right atrium called the sinoatrial (SA) node serves as a natural pacemaker for the heart

Within the floor of the right atrium is another pacemaker, the atrioventricular (AV) node.

angi/o - vessel,swelling of a vessel vas/o - vessel, suturing of a vessel aort/o - aorta, narrowing or stricture of the aorta arteri/o -artery, abnormal condition of hardening of an artery ather/o -thick fatty, thick, fatty tumor atri/o - atria, pertaining to the atria and the ventricles cardi/o - heart,condition of a rapid heart rate coron/o -heart, pertaining to the heart electr/o - electricity, record of electricity of the heart hem/o - blood, pertaining to the destruction of blood hemat/o - blood, vomiting of blood phleb/o - vein, rupture of a vein ven/o - vein, stopping of a vein thromb/o - thrombus (clot), inflammation of a vein with the presence of a clot valv/o - valve, cutting into or incision of a valve valvul/o -valve, surgical repair of a valve vascul/o -blood vessel, creation of a blood vessel ventricul/o - ventricle, mouthlike opening into a ventricle