How Does Cholesterol Contribute To A Heart Attack?

Dr. Steven Nissen answers the question: 'Cholesterol And Heart Attacks?'

ByABC News
November 12, 2008, 2:10 PM

— -- Question: How does cholesterol contribute to a heart attack?

Answer: Well, cholesterol is really one of the main risk factors for having a heart attack. And we believe that the mechanism, which is pretty well understood, involves LDL, so called bad cholesterol gets into the vessel wall. And when it gets into the wall of the vessel, it builds up these plaques in the wall. And eventually, after enough plaque has formed in the coronary arteries, one of them actually ruptures. And when the plaque ruptures, a blood clot occurs, and that blood clot shuts down blood flow to a part of the heart muscle. And that's what a heart attack is.

Now, it's important also to understand, however, that there is another form of cholesterol -- HDL, known as good cholesterol -- which actually is pulling the cholesterol out of the vessel wall. And so there's a constant tug-of-war that goes on in everybody's vessel wall -- with the bad cholesterol trying to get in where it's going to cause trouble, and the good cholesterol trying to pull it out where it's going to protect the patient. And that's why we try to raise good cholesterol and lower bad cholesterol to prevent heart attack.

Next: How Significant Is The Role Of Cholesterol In Heart Disease And Stroke?

Previous: What Are The Roles Of Diet And Exercise In Determining Cholesterol Levels?