The heart is a pump that sits in the chest behind the breastbone. Normally the heart is a little bigger than a fist. The heart is divided into a right and left side. Each side is further divided into a top and bottom half.
See Illustration: Normal Heart
Blood from the body enters the top right side of the heart (the right atrium) and passes into the lower right side (the right ventricle). Here the blood is sent to the lungs to pick up oxygen.
This oxygen-rich blood returns to the heart at the top left side (the left atrium) and then passes into the lower left part of the heart (the left ventricle). This part of the heart is the strongest because it pumps oxygen-rich blood to all parts of the body.
The muscle of the left ventricle is thick and can't get its own blood supply directly from the blood it's pumping inside the chamber. The coronary arteries run over the outside surface of the heart and provide blood to feed the muscle from the outside.
Cardiovascular diseases are diseases of the heart and blood vessels, such as coronary artery disease (CAD), heart attack, high blood pressure, stroke, angina (cardiac chest pain), and rheumatic heart disease. CAD is a disease of the blood vessels of the heart that causes heart attacks.
See Illustration: Heart and Coronary Arteries
CAD develops as the blood vessels of the heart become narrowed or blocked. When fatty deposits called "plaques" collect along the artery walls, they slow the blood flow to the heart.
See Illustration: Atherosclerosis
This narrowing of the blood vessels often has no symptoms until it causes the coronary arteries to become so narrow that blood flow is decreased to parts of the heart, resulting in a type of chest pain called angina (or angina pectoris).
If the blood vessel becomes completely blocked, the result is a heart attack. During a heart attack, a portion of the heart receives no blood and there is the possibility that the heart muscle will be damaged.
Heart disease is the leading cause of death for both men and women in the United States, accounting for about one million deaths each year. Nearly half of all cardiac events (such as a heart attack) happen in people with no personal history of heart disease. About 85 percent of people who die as a result of heart disease are 65 or older.
Many factors can contribute to the onset of coronary artery disease, which usually develops over time. Some of these can't be changed, such as a family history or increasing age. However, there is a lot you can do to reduce your risk of developing coronary artery disease. The lifestyle choices you make can go a long way to preventing heart disease.
About 25 to 30 percent of patients with heart disease have no common symptoms. Often, the first signs of heart disease might be chest pains during exertion or a heart attack. Other symptoms include:
At Kaiser Permanente, our primary care doctors work with heart care experts to make sure patients receive the best care possible. Along with your providers, we offer the support and resources to help you live a healthy life.