se with moderate blockages (p. 52).
Understanding how the heart functions and how damage occurs is necessary so that appropriate treatments can be developed. The heart is a pump which beats more than 100,000 times a day, pushing 4,500 gallons of blood through 60,000 miles of blood vessels to supply oxygen and nutrients to tissues of the body (Zugibe, 1986, pp. 1-3). Coronary artery disease, which results in heart attacks, is caused by the clogging of the coronary arteries, the arteries which supply blood to the muscles of the heart (the myocardium). A heart attack occurs when the blood supply to the heart is interrupted. This is usually caused by a blood clot, most frequently occurring at an area in the vessel where plaque has formed (Zugibe, 1986, pp. 1-3). Interruptions in blood flow may be minor and cause temporary discomfort, but if they are prolonged or a large part of the heart muscles is involved, death of some of the heart tissue may occur (myocardial infarction).
Plaque forms at an area of injury to the lining of blood vessels. This injury often occurs when the blood pressure is elevated. The tear attracts collagen and clotting proteins to repair the damage and cholesterol (LDL or "bad" cholesterol) is deposited at the sight. HDL or "good" cholesterol binds fats and transports them out of the circulation to the liver for processing.
Platelets, the particles in blood responsible for forming clots, are also attracted to the site, and calcium may be deposited in the plaque. The plaque narrows the lumen of the blood vessel, restricting blood flow. A coronary blood vessel can be two-thirds blocked and present no symptoms until a person is under stress or a spasm occurs in the coronary artery (Gordon & Gibbons, 1990, p. 55-57). Plaque begins to form early in life, as was confirmed by the examination of young soldiers killed in WWII and Vietnam (Ornish, 1990, p. 50).
The factors responsible for c...