The heart is a fist-sized muscle that pumps blood through the body 24 hours a day, 365 days a year without rest. The normal heart is made up of four parts: two atria on the top of the heart (right atrium and left atrium), and two ventricles (right and left ventricles), the muscular chambers on the bottom that provide the major power to pump blood. These four chambers are connected by valves that allow blood to move forward and prevent it from flowing backward. Coronary arteries, or blood vessels, deliver a constant, nourishing supply of blood to the heart muscle.
The heart’s pumping action, or “heartbeat”, is directed by a complicated electrical system. Problems with the regular heartbeat, such as abnormally fast or slow rhythms, can be caused by heart attack (myocardial infarction) or aging, but may happen for other reasons as well. Heart rhythm problems can cause the feeling that the heart is “racing” (palpitations), weakness, passing out (syncope), and sometimes death.
Blockages in the coronary arteries can also cause major problems in the heart because they slow or stop the flow of blood to the heart muscle. If the heart does not get enough blood, chest pain (angina) or muscle death from a heart attack (myocardial infarction) can result.
We can all do a great deal to lower the risk of heart disease and maintain a normal heart function. Regular exercise, a healthy diet, maintaining a healthy weight, controlling cholesterol and blood pressure, and not smoking are ways we can all protect our hearts. Some people, however, are born with a tendency to have heart disease or other illnesses that may affect the heart.