Task force advises cardiac screening with ultrasound, CT

A cardiology task force is recommending that two tests, CT for coronary artery calcium and ultrasound for carotid intima-media thickness and plaque assessment, be used to screen asymptomatic patients for heart attack risk.

The recommendations are part of a new practice guideline for screening subclinical cardiovascular disease in the asymptomatic at-risk population. The guideline was developed by the SHAPE (Screening for Heart Attack Prevention and Education) task force, which is composed of an international contingent of leading cardiologists and researchers. CT and ultrasound were chosen because of their predictive value, availability, reproducibility, complementary value, and cost-effectiveness.

The SHAPE guideline, which appeared in the July 10 issue of the American Journal of Cardiology, calls for screening of all asymptomatic men between 45 and 75 and women between 55 and 75 to assess coronary plaque buildup and carotid wall thickness. An analysis by the SHAPE Task Force estimates that screening this population could prevent more than 90,000 deaths annually while substantially reducing the number of heart attacks and saving up to $21.5 billion in healthcare and related costs.

"Until SHAPE, there had been no national guidelines for screening subclinical coronary heart disease," said Dr. Morteza Naghavi, chairman of the task force. "We encourage hospitals, diagnostic clinics, and physicians to comply with SHAPE standards and provide patients with state-of-the-art preventive care."

Heart attack and stroke account for more death and disability than all cancers combined, according to the task force. And while multiple screening tests are in use to detect subclinical cancers in the breast or colon, for example, the same is not true for subclinical atherosclerosis, which underlies both heart attack and stroke. This void leaves many individuals - even some with severe atherosclerosis - unaware of their risk because they have no symptoms, according to Dr. Daniel Berman, director of cardiac imaging at Cedars-Sinai Medical Center in Los Angeles and a member of the task force.

This year, more than 500,000 Americans will have a first heart attack, and almost all of these are expected to come from the SHAPE-eligible population, he said.

Atherosclerosis underlies nearly all cases of heart attack and most cases of strokes. "Vulnerable patients," individuals with the highest degree of atherosclerotic plaque burden, exhibit no signs of heart disease and are not identified as very high risk by traditional risk factor assessment.

Relying solely on traditional risk factors to identify patients at risk for a heart attack has not been successful, Berman said. To reliably identify individuals at risk of heart attack requires an assessment of the total atherosclerotic plaque volume, structure, and function of their arteries. The means for doing so are detailed in the SHAPE guideline, according to Dr. Erling Falk, a pioneering cardiovascular pathologist from Aarhus University in Denmark who served on the task force.

"With the publication of the SHAPE guideline, we hope to build a new momentum in cardiology that inspires physicians to use modern technologies for the prevention of heart attack, rather than using expensive technologies only to treat heart attack, which is too late and results in too little benefit to the patient," said Dr. P.K. Shah, director of the division of cardiology at Cedars-Sinai and a member of the task force.