(HealthDay News) -- A simple test that detects blockages in coronary arteries may help doctors identify patients with "silent" heart disease without requiring major new medical expenses.

The findings were released in a study in the Sept. 29 issue of the Journal of the American College of Cardiology.

The tests -- coronary artery calcium scans -- pinpoint clogs in coronary arteries caused by plaque. While they can warn doctors that certain patients are at risk of developing heart disease, insurance companies have been hesitant to cover them because they could lead to expensive tests that might not turn up anything.

Still, "over half of patients who suffer heart attacks have no warning that they have heart disease until the heart attack occurs. If we knew the patients were at risk, current treatments could prevent the majority of these unnecessary events," according to Dr. Daniel S. Berman, chief of cardiac imaging at the S. Mark Taper Foundation Imaging Center of Cedars-Sinai Heart Institute, Los Angeles. "We had to address the concerns about unnecessary testing and costs related to this potentially lifesaving procedure," he said in a news release from Cedars-Sinai.

In the new study, researchers performed the scan on 1,361 volunteers who were at intermediate risk of heart disease (neither high nor low risk) and followed them for four years.

High scores, indicating more plaque, were linked to higher risk of heart problems. Those with low scores, however, got fewer tests and the costs were lower, suggesting the tests won't lead to hugely expensive tests in the general population of those who are screened.

Heart disease is the top cause of death in the United States, killing an estimated 652,091 people each year, according to the U.S. Centers for Disease Control and Prevention.

The Eisner Foundation, a private philanthropy in Los Angeles, financed the study. GE Healthcare, maker of one of the imaging machines used in the study, has provided research support, grant support or consulting fees to several of the study authors.

More information

Learn more about heart attacks from the American Heart Association.