Common blood test could detect heart disease

WASHINGTON - An improved version of a common emergency room blood test could be used to detect heart disease in apparently healthy patients, according to a US study published Tuesday.

A less sensitive test for the protein, called cardiac troponin T (cTnT), is already used by ER doctors who want to test whether a patient who is complaining of chest pains is actually experiencing a heart attack.

The new, more sensitized version was able to detect the protein in about 25% of samples provided by more than 3,500 middle-aged people.

"This test is among the most powerful predictors of death in the general population we've seen so far," said James de Lemos, associate professor of internal medicine at University of Texas Southwestern and lead author of the study.

"It appears that the higher your troponin T, the more likely you are to have problems with your heart, and the worse you're going to do, regardless of your other risk factors."

The new test "can detect circulating cTnT levels in almost everyone with chronic heart failure and chronic coronary artery disease," said the study.

"People with detectable levels of troponin T were nearly seven times more likely to die within six years from heart disease," added the study, published in the Journal of the American Medical Association.

The research followed more than 3,500 people, whose ages ranged from 30 to 65, from 2000 to 2007. Subjects gave blood samples and submitted to multiple body scans, magnetic resonance imaging (MRI) and computed tomography (sectional imaging) to examine the heart and other organs.

"This study was designed to be representative of urban communities throughout the United States where there is a high prevalence of obesity, untreated hypertension and diabetes -- just as there is in Dallas," de Lemos said.

The most elevated levels of cTnT were detected among older adults, men, African-Americans and people who suffered "abnormal thickening or weakness of the heart muscles."

De Lemos said he hoped "in the future to be able to use it to prevent some death and disability from heart failure and other cardiac diseases."

Heart disease is the number one killer of Americans, according to the Centers for Disease Control, which said last year that 785,000 Americans had a new coronary attack, and about 470,000 had a recurrent attack.