When fatty streaks of plaque build up in the inner lining of your arteries, this is known as calcification. Soft plaque is made up primarily of cholesterol (fatty deposits), collagen and other components of connective tissue, all bound together with calcium deposits. This type of plaque causes the lining of the arterial wall to become inflamed.
Over time, the inflammation causes tissue damage and changes the structure of the artery's wall. This is called oxidation. Oxidation causes the soft plaque to develop a hard shell, turning it into hard calcified plaque. Hard plaques keep the blood from flowing through the artery by growing in size, or they can cause heart attacks by rupturing and causing the formation of a blood clot.
In the process of hardening, plaques accumulate calcium. That's why doctors monitor levels of calcium buildup: the more calcium present in your blood vessels, the more hard plaques will be present, and the more at risk you that your blood supply will get disrupted. Calcium buildup can be reduced if it is caught early enough by simple lifestyle changes: improving your diet or getting more exercise.
Atherosclerosis is the leading cause of heart attacks, affecting more than 1.5 million Americans each year, killing about 500,000 of them.
The American Association of Physicists in Medicine contributed to the TV portion of this report.