Saturday, August 25, 2012

Heart Calcium Scan Most Effective in Predicting Risk of Heart Disease, Study Shows


More than 1 million people in the United States will have a heart attack this year. Most will occur in people with no symptoms. (Based on the data available, the incidence of coronary heart disease in Malaysia is estimated to be 141 per 100,000 population OR 41,500 persons this year)

With better prediction methods for cardiovascular disease, many of those could be prevented.

Coronary artery calcium, carotid intima–media thickness, ankle-brachial index, brachial flow–mediated dilation, high-sensitivity C-reactive protein(CRP), and family history were independent predictors of incident cardiovascular disease (CVD)/coronary heart disease (CHD) in intermediate-risk individuals.

One new study by researchers at Wake Forest Baptist Medical Center found that coronary artery calcium provided superior discrimination and risk reclassification compared with the other risk markers.

The heart's arteries can develop a substance called plaque in their walls. Cholesterol and other cells compose the plaque. Too much plaque buildup can trigger a heart attack.

The test, known as coronary artery calcium (CAC), uses a CT scan to detect specks of calcium in the wall of the arteries around the heart. These calcifications are an early sign of plaque buildup.

About 7,000 participants, 1,330 of whom had intermediate risk, without diabetes mellitus, and had complete data on all 6 markers were included in the study.

Coronary artery calcium scan provided superior discrimination and risk reclassification compared with other risk markers.

“Additional research is needed to explore the costs, benefits and risks of widespread use of CAC screening in people at risk of heart disease,” said Joseph Yeboah, M.D., assistant professor of cardiology at Wake Forest Baptist and lead author of the st

Besides costs, one potential issue is the radiation involved in the test, which is about 1 millisievert. That's about one-third the amount of radiation Americans are exposed to from the environment in one year, according to the U.S. Food and Drug Administration. A CT scan to the head is 2 mSv.

Still, it's unclear what effect the radiation from the calcium test would have over time, especially since there has not been a set standard for the radiation involved in the test, Yeboah said. The FDA has not weighed in about this test.


The above story is based on the August 21, 2012 provided by Wake Forest Baptist Medical Center.

The study findings are presented in the Aug. 22 issue of the Journal of the American Medical Association:

Yeboah J, McClelland RL, Polonsky TS, Burke GL, Sibley CT, O’Leary D, Carr JJ, Goff DC, Greenland P, Herrington DM. Comparison of Novel Risk Markers for Improvement in Cardiovascular Risk Assessment in Intermediate-Risk Individuals.  JAMA. 2012;308[8]:788-795 doi:10.1001/jama.2012.9624

Coronary Artery Calcium Scan is available at several hospital in Malaysia. A basic cardiac evaluation with  calcium scan costs RM800.00. We suggest you talk to your regular family physician first, if you are considering a scan.

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