Although several professional societies support CAC scoring to guide treatment decisions, the U.S. Preventive Services Task Force (USPSTF) has stated that there is currently insufficient evidence to recommend it for widespread use in preventing cardiovascular events. One reason: It is not yet clear whether using CAC scans routinely reduces heart attacks or deaths.
The test also has limitations. It does not detect soft plaque, which may be more common in smokers and people with diabetes. In these groups, the scan may underestimate risk.
“The challenge for us is that sometimes we have a patient in front of us who is very high risk even if the calcium score is not elevated,” Dr. Giaimo says.
Another concern is the potential for anxiety in patients who have positive results. “The tool is meant to help improve preventative measures aimed at reducing the likelihood of heart attacks in the future, but a positive result can lead to significant patient anxiety,” Dr. Levin says.
In addition, 10% of CAC scans show findings unrelated to the heart, such as lung or thyroid nodules. Most of those findings are not dangerous, but they can lead to additional testing, Dr. Levin says.
Dr. Giaimo says a CAC screening should not routinely lead to further testing, such as stress tests or invasive procedures. But a person’s score can show how significant their cholesterol is and guide treatment. “The CAC scan is a screening tool that should motivate improvements in risk factors,” he says.
