Blood test can tell about heart attack risk

Washington: A simple blood test can identify people who are at risk of heart attack, even those who don't have high cholesterol, research says.

The new test measures gamma-prime fibrinogen, a component of the blood's clotting mechanism.

Its elevated levels indicate greater likelihood of a heart attack, even when other signs don't point to cardiovascular trouble, says David H Farrell, professor of pathology at the Oregon Health & Science University (OHSU) School of Medicine.

"Half a million people suffer fatal heart attacks each year," Farrell says.

"About 250,000 patients who die have normal cholesterol and some of the patients with normal cholesterol also have elevated levels of gamma-prime fibrinogen. We think this is another risk factor that we should test for," he adds.

Farrell and his team confirmed the effectiveness of the gamma-prime fibrinogen test by analysing 3,400 blood samples from the landmark Framingham Heart Study, the oldest and most prestigious cardiovascular disease study in the world.

Besides, OHSU's analysis of the Framingham samples found that patients with well-established heart attack risk factors, including high cholesterol, high body mass index, smoking and diabetes, also have elevated gamma-prime fibrinogen levels.

"We found that if your gamma-prime fibrinogen levels were in the top 25 percent, you had seven times greater odds of having coronary artery disease," Farrell says.

A small pilot study in 2002 gave OHSU researchers their first inkling that the component might be linked to heart disease.

They obtained the Framingham samples - which are rarely shared - and proved the link. The next step is using the test at several hospitals and medical centres to demonstrate it works on a large scale, an OHSU release said.

"It will take some time to build consensus within the field of cardiology for this test," Farrell says.

"The test will be used in conjunction with a cholesterol test to better predict who is likely to suffer a heart attack. Ultimately we are optimistic we can identify people who didn't know they are at risk," he adds.

The results were published in Clinical Chemistry.