A team led by researchers at Weill Cornell Medical College has found that a non-invasive scan can accurately predict the likelihood of a heart attack or death over a 15-year period, even if the patients are not showing symptoms of heart disease.

Lead researcher Dr. James Min, director of the Dalio Institute of Cardiovascular Imaging at New York-Presbyterian Hospital and Weill Cornell Medical College, called the scan — a coronary artery calcification test, which measures calcified plaque buildup in the arteries — a “mammogram for the heart”.

The study is the largest, in both size and scope, to show a connection between coronary artery calcification test results and long-term patient prognosis, according to Min.

For the study, which was published Monday in Annals of Internal Medicine, researchers looked at the medical records of 9,715 patients in the Nashville, Tenn. area who had undergone a coronary artery calcification using either electron beam tomography or multislice computed tomography between 1996 and 1999. The patients did not have symptoms of coronary artery disease, but doctors who were treating them collected information on their cardiac risk factors, including high cholesterol and high blood pressure, as well as a history of diabetes, and family history of heart disease.

The researchers, which included investigators from Emory University School of Medicine in Atlanta and Cedars-Sinai Medical Center in Los Angeles, grouped the patients by their Agatston score, or the extent of coronary artery calcification, which ranges from 0 to more than 1,000.

Using the patients’ Agatston scores and cardiac risk factors, the researchers calculated their all-cause mortality risk, or the risk of death from any cause, and then tracked their status through the National Death Index. They found that the Agatston score was highly predictive of all-cause mortality, with overall 15-year mortality rates for 936 of the study participants ranging from 3 percent to 28 percent for Agatston scores ranging from 0 to 1000 or greater.

Min says the coronary artery calcification test, which costs less than $100, is better than any other diagnostic heart test for predicting heart attack risk in symptomatic patients.

“You could do stress tests or labs, such as a cholesterol test, but nothing can predict it better,” Min told DOTmed News. “Every piece of evidence that we have shows that this identifies heart disease much earlier — before any manifest clinical events occur.”

Min says the next step is to conduct a large-scale randomized trial to show that patients have better outcomes if they receive treatment based on the results of a coronary artery calcification test. The researchers have put together a design for a trial, which will also be led by Weill Cornell Medical College.

Coronary artery calcification scans are not generally covered by insurance, Min says. Texas is the only state to mandate coverage, under a law passed in 2009.

In 2012, the American Heart Association issued a position statement, saying that it didn’t support state efforts to mandate coverage of the scans because there was insufficient evidence showing that widespread screening of patients without symptoms of heart disease is clinically appropriate.

“Until stronger and more granular evidence for the efficacy of coronary artery calcification (CAC) scans and carotid IMT ultrasound screenings for CHD in the asymptomatic adult population is established, the AHA does not support state efforts to mandate coverage for these CHD screening methods,” the statement read. “Instead, AHA recommends that individual patients should discuss alternative guideline recommended CHD screening options with their physicians and make decisions that are consistent with the best available information based on the current science.”