Plaque can build up inside your arteries. Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. Over time, plaque hardens and narrows your arteries. This limits the flow of oxygen-rich blood to your organs and other parts of your body.
What is vulnerable plaque?
Vulnerable plaque is a kind of atheromatous plaque – a collection of white blood cells (primarily macrophages) and lipids (including cholesterol) in the wall of an artery – that is particularly unstable and prone to produce sudden major problems such as a heart attack or stroke.
Patients with this kind of plaque may not feel any symptoms. In the early stages of the process, the change in blood flow may not be detected with standard testing. Researchers are looking at unique scanning techniques that might highlight the presence of vulnerable plaque.
What causes vulnerable plaque?
- 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.
Can vulnerable plaque be detected?
Cardiologists have found that by measuring the level of a substance called C-reactive protein in the bloodstream, they can predict a person’s risk of heart attack or stroke. C-reactive protein is a marker that doctors use to measure inflammation activity in the body. Two large studies showed that the higher the C-reactive protein levels in the blood, the greater the risk of a heart attack.
Not all vulnerable plaque ruptures, and researchers are looking at ways to determine which vulnerable plaques are most likely to rupture. They found that the warmer the plaque, the more likely it will crack or rupture.
Can it be prevented or treated?
Patients can lower their C-reactive protein levels in the same ways they can cut their heart attack risk (healthier lifestyles). Doctors can check the C-reactive protein levels with a blood test, and many doctors are adding the test to their patients’ cholesterol screening.
Recent studies show smoking is very dangerous for people who have vulnerable plaque in their arteries. The nicotine in cigarettes directly affects the inflammatory response, causing the release of more cytokines. Researchers are also studying how family history and genes factor into the inflammation process.
Medicines used for treating high blood pressure and aspirin, appear to reduce inflammation in the body, that might prevent heart attacks in people who already have high C-reactive protein levels.
Cholesterol lowering medicines called statins have been found to lower C-reactive protein levels. Doctors are now looking at how these medicines may be used to prevent heart attacks in people with normal cholesterol levels. Doctors are still studying the use of cholesterol-lowering medicines for this purpose.