Are Calcium Heart Scans Worth It? Study Shows Limited Value Except for Borderline Risk
- A popular screening test that checks for plaque in the arteries feeding the heart may offer limited value for most people, according to a study published in the...
- Heart disease remains the leading cause of death for both men and women in the United States, driving high demand for preventive screenings.
- Despite the overall findings of limited utility, the research identified one notable exception.
A popular screening test that checks for plaque in the arteries feeding the heart may offer limited value for most people, according to a study published in the journal JAMA. Researchers found that coronary artery calcium (CAC) scans often provide little additional insight beyond what clinicians can determine using standard risk calculators alone.
Understanding the Limitations of Calcium Scans
Heart disease remains the leading cause of death for both men and women in the United States, driving high demand for preventive screenings. The CAC test uses a computed tomography (CT) scan of the chest to detect calcified plaque in the coronary arteries, yielding a score that estimates a patient’s risk of experiencing a heart attack or stroke within the next few years. A score of zero typically indicates no detectable plaque and a low risk, while scores above zero—and particularly above 100—point to progressive disease and elevated risk. However, the study revealed that most individuals can obtain the same risk assessment simply by using the American Heart Association’s PREVENT risk calculator. The tool accounts for vital risk factors including age, sex, blood pressure, cholesterol levels, diabetes status, smoking history, and kidney function. Across a group of more than 6,000 participants aged 45 to 79 followed over a 10-year period, factoring in CAC scores barely altered the risk classifications for the majority of the population.
When CAC Scans Serve as a Tiebreaker
Despite the overall findings of limited utility, the research identified one notable exception. For patients placed in the “borderline” or “intermediate” risk category by the PREVENT calculator—meaning a 3% to 9% predicted risk of heart disease over 10 years—adding a calcium score made a tangible difference. In these specific cases, the scan successfully reclassified most individuals into more definitive high- or low-risk tiers. Nilay Shah, senior author of the study and assistant professor of medicine in the cardiology division at Northwestern University Feinberg School of Medicine, noted that the use of calcium scores has expanded rapidly as the scans have become more accessible and affordable. Shah explained that a CAC score functions best as a tiebreaker for middle-risk patients who are uncertain about initiating preventative therapies, such as cholesterol-lowering statins. Evidence of plaque suggests starting medication, whereas a score of zero indicates that patients can delay treatment. This targeted approach aligns with updated cholesterol guidelines issued jointly by medical organizations including the American College of Cardiology and the American Heart Association, which recommend CAC scans primarily to guide therapy decisions in middle-risk groups. Socrates Kakoulides, a cardiologist and chief imaging officer of Baptist Health Heart & Vascular Care who was not involved in the research, said that the findings help refine patient selection for the procedure rather than discrediting the technology.
