Unhealthy cholesterol, particularly low-density lipoprotein (LDL) cholesterol, forms a fatty substance called plaque, which builds up on the arterial walls of the heart. Smaller plaques remain soft, but older, larger plaques tend to develop fibrous caps with calcium deposits.
|Click the icon to see an image of the developmental process of atherosclerosis.|
The long-term result is atherosclerosis, commonly called hardening of the arteries. The heart is endangered in two ways by this process:
- Eventually these calcified and inelastic arteries become narrower (a condition known as stenosis). As this process continues, blood flow slows and prevents sufficient oxygen-rich blood from reaching the heart. This condition leads to angina (chest pain) and, in severe cases, to heart attack.
|Click the icon to see an image of a heart attack.|
- Smaller unstable plaques may rupture, triggering the formation blood clots on their surface. The blood clots block the arteries and are important causes of heart attack.
Review Date: 04/06/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.