Lifestyle

The Heart Scan That Can Spot Hidden Plaque Before Symptoms Start, and Why Your Checkup May Not Include It

By Erica Coleman · November 1, 2026

A checkup usually covers blood pressure, cholesterol and family history. For people whose heart risk is hard to call, a quick scan can look directly at the heart’s arteries.

It is called a coronary calcium scan, or calcium score test. Cleveland Clinic describes it as a CT scan that looks at how much calcium is in your coronary arteries. Calcium there can show a buildup of plaque, a waxy, fatty substance that can narrow or block the arteries. That means a person could have coronary artery disease, which could lead to a heart attack.

The scan itself is simple. Cleveland Clinic says the CT portion takes only a few minutes and the whole visit about 10 to 15 minutes. No contrast dye is injected. Patients may be asked to hold their breath for 10 to 20 seconds. People can go back to normal activities and eat as usual afterward.

The result is a number. MedlinePlus says a score of 0 means the chance of having a heart attack over the next several years is very low. Scores above 0 indicate plaque, and MedlinePlus groups them this way: 1 to 9 minimal, 10 to 99 mild, 100 to 299 moderate, 300 to 999 severe, and 1,000 or above extreme. The higher the score, the more severe the problem may be.

Research supports its value as a risk tool. In 2023, the National Heart, Lung, and Blood Institute reported on research in JAMA involving more than 3,000 adults ages 45 to 79. The researchers found that coronary artery calcium scans significantly improved 10-year risk predictions for heart disease. The authors said older adults, or adults with underlying risks, may benefit from learning about early signs of plaque, which could inform decisions they make with their physician.

So why isn’t it part of every checkup? Because it helps some people far more than others. Cleveland Clinic says results are most helpful for people who don’t have a clear high or low risk, but are somewhere in the middle. It says the test could help people between ages 40 and 70 who are at increased risk but don’t have symptoms. Increased risk includes a family history of heart disease, past or current tobacco use, high cholesterol, diabetes, high blood pressure, overweight or obesity, and an inactive lifestyle.

Cleveland Clinic also lists people who may not benefit. They include people with no heart risk factors, those already at high risk, anyone with diagnosed coronary artery disease or symptoms that suggest it, and people who want to know whether their heart treatment is working. Those people should talk with a provider about other tests.

The scan has limits. Cleveland Clinic says it can’t detect certain forms of disease, such as soft plaque, so it isn’t absolute in predicting a heart attack or stroke. It calls the scan another tool providers can use to decide whether a person needs a statin. There is a very small cancer risk from the radiation, which the clinic compares to about the amount a person naturally gets in a year.

If a score comes back high, Cleveland Clinic says a provider may recommend a statin, more exercise, diet changes, more tests or more follow-up visits.

The best way to raise it is as a question, not a demand. Bring your family history and recent cholesterol and blood pressure numbers to your next visit, and ask whether a calcium score would change your treatment.

This article is for general information and is not medical advice. Talk with your doctor about whether a calcium score test makes sense for you, and call 911 for chest pain or other signs of a heart attack. This article was produced with the assistance of AI and fact-checked against the sources cited by LightWave Reports.