A New Marker May Identify Persons at Risk for Heart Disease

Heart attack is the number one killer in America. But more than 25% of those who have a heart attack seem outwardly healthy. Dr. Bernadine Healy is in Washington to tell us about a new blood "marker" that might help identify who is at risk.

The New England Journal of Medicine has published the results of two back-to-back studies that show certain "markers" in our blood could indicate who is likely to suffer chronic heart disease or acute heart attacks. Of the people who currently have heart disease and heart attacks, about 25% do not have any of the known risk factors. That's why these new studies are so exciting. If the findings were true, they would identify another element to add to the list of known heart disease and heart attack risk factors such as high cholesterol and obesity.

Specifically, these markers indicate the likelihood of inflammation of one's heart and arteries. The caveat is: there is small chance that these markers are not "predictors" of heart disease and heart attack, but rather a by-product of heart disease and heart attack.

A Glasgow University study published in the New England Journal of Medicine finds a potential new risk factor for heart disease and heart attacks. An enzyme that flows through the blood with low-density lipoprotein, LDL, the molecule that holds "bad cholesterol," appears to play a direct role in heart attacks.

The Glasgow study finds the enzyme, Lipoprotein-associated phospholipase A2 Lp-PLA2, may serve as a "marker" to predict heart attack. This new marker could serve a target for future treatments to prevent heart attacks. "Not everyone who suffers a heart attack is found to have above-normal cholesterol levels. So it is important that we examine other potential factors like Lp-PLA2 if we are to continue to reduce the toll of heart disease," said the primary author of the report, Dr. Chris Packard.

It's an interesting and exciting study. It's about biochemical windows and it gives us an idea about what actually causes narrowing of arteries, or heart attack. It also gives us predictions about who is at risk. Triponin-t is a measure of clot formation and muscle injury, it is a window into cause of patient's chest pain

These are predictors, just like other risk factors:

high cholesterol
high blood pressure
obesity
lack of exercise
genetic make up
age

Emerging New Risk Factors:

biochemical markers of inflammation
infectious agents (viruses / bacteria)
vitamin B and folic acid deficiency (homocystine)

There are three phases we have to deal with:

(1) CAUSATION - lipids build up in blood vessels; cause chronic disease in blood vessels; clots obstruct blood vessels.

(2) PREDICTION - risk factors

(3) PREVENTION / TREATMENT

Chronic heart disease - builds up over the year
Acute attack is caused by lipids (fatty plaques - cholesterol treatment) and blood clots, we treat clots with aspiin or other blood thinner.

Heart disease is the number one killer in the US. We have to figure out who is at risk. But 25% of victims have no recognized risk factors.

Inflammation is body heightening its immune system and sending white cells that cause swelling. For example, sore throat is an inflammation, a swelling and white cell concentration. Damaged tissue can be caused by door slam or by virus or bacteria.

These studies identified emerging biochemical markers that show when the heart or its blood vessels are facing inflammation. Studies look for heart-specific measures that relate to what's happening in the arteries and heart muscle.

Hearts and arteries susceptible to inflammation are likely to have chronic or acute coronary syndrome - inflammatory markers are predictors of heart attack - level is higher than for chronic sufferer's.

Inflammation plays a role in BOTH chronic and acute events. The first study found that inflammation plays part in build-up oplaque to blood clots and to acute event, or heart attack.

The second study looked at "blood constituents" and found that phosolipase a-2 is predictive of chronic disease. It also looked at c-reactive protein, and white blood cell count.

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