Vulnerable Plaque, the Time Bomb

 

The body's normal reaction to injury  is swelling, or inflammation, to the affected area. What many people may not be aware of is the fact that inflammation also may occur within the walls of the arteries.

This inflammation leads to the formation of "soft" or vulnerable plaque, which includes not only the debris that clogs an artery, but also various cell types whose function is to assist with the clotting of the blood.

 

What causes vulnerable plaque?

Researchers now believe that that vulnerable plaque is formed by the following process:

  • Fat droplets are absorbed by the artery, which causes the release of proteins called cytokines that lead to inflammation.
  • The cytokines make the artery wall sticky, which attracts immune-system cells called monocytes.
  • The monocytes squeeze into the artery wall. Once inside, they turn into cells called macrophages and begin to soak up fat droplets.
  • The fat-filled cells form a plaque with a thin covering.

When this inflammation is combined with other stresses, like high blood pressure, it can cause the thin covering over the plaque to crack and bleed, spilling the contents of the vulnerable plaque into the bloodstream. The sticky cytokines on the artery wall capture blood cells (mainly platelets) that rush to the site of injury. When these cells clump together, they can form a clot large enough to block the artery.

 

Click to view larger image

Different Types of Vulnerable Plaques Movie



Multimedia Features


reach md
Part 1: Listen Now Part 2: Listen Now
  Download   Download


 

 
View our Multimedia Section (SHAPE public service announcements, videos, and images) and Media Center.
Quiz & Poll
  Patient's Question
Which condition is more dangerous? (better predicts a near future heart attack)
    High blood cholesterol
    High coronary calcium
  Doctor's Question
Would you treat individuals with normal cholesterol but high coronary calcium or carotid IMT?
    No
    Yes