Atherosclerosis results from the gradual buildup of fatty deposits called plaque, or lesions, in the interior walls of large and medium-sized arteries. The disease process starts with small changes in the artery wall and takes years to develop to a point where the narrowing arteries may produce symptoms or negatively affect your health.
Narrowing in the heart’s arteries leads to coronary heart disease (CHD), also called coronary artery disease (CAD). CHD gradually starves the heart muscle of the high level of oxygenated blood that it needs to function properly. A lack of adequate blood supply to the heart typically produces symptoms that range from angina and unstable angina to heart attack or sudden death.
Narrowing of the carotid arteries that carry blood to the brain increases your risk of stroke. Narrowed arteries in your legs or arms results in peripheral artery disease (PAD).
The term atherosclerosis comes from two Greek words — athero (paste, gruel) and sclerosis (hardness) — that may give you a graphic image of hardened sludge. Not a pretty picture, is it? But it’s an apt image for these deposits of cholesterol, other fats, cellular wastes, platelets, calcium, and other substances.
These deposits typically start with fatty streaks and grow to large bumps that distort the artery and block its interior where the blood must flow. Some plaques are stable and others are unstable or vulnerable to cracking or rupturing, which often leads to an artery-blocking blood clot and subsequent heart attack. The sections that follow profile that development process.
During the last 15 to 20 years, evidence from extensive population studies and clinical research has increased doctors’ understanding of the many factors and pathways that contribute to the beginnings and progress of atherosclerosis. The next sections provide an overview of medical science’s best understanding right now; however, you need to remember that new studies continually add to the knowledge of this complex, multifaceted disease.