What Do My Heart Scan Results Mean?

Heart scans, also known as coronary calcium scans, are becoming common screening tools for early detection of heart disease. But why do heart scans matter, and what does your heart scan number really show about your risk of heart disease or stroke? 

Franciscan Health cardiologists explain the benefits of a heart scan in helping prevent heart attacks and when it’s best to have a calcium test for the heart.

What Is A Heart Scan?

A heart scan offers signs of your heart's health. While calcium is an indicator of bone health, this test isn't related to calcium in your diet. This calcium test evaluates the health of your blood vessels. In general, a heart scan can help a physician to estimate how much calcified plaque a patient has in their coronary arteries and what a patient's relative risk is of having a heart attack over the next 5 to 10 years.

“The heart scan test is a non-invasive outpatient test, and it basically entails placing small pads on your chest to track your heart rhythm,” said cardiologist George Lolay, MD, with Franciscan Physician Network Indiana Heart Physicians in Indianapolis. “We would ask you to lay flat on a CT scanner table, and then the table would go through that scanner. We might ask you to hold your breath for a few seconds, but your head will always be outside of the scanner. And the entire test shouldn't take more than 10 minutes. Usually you would leave with the results same day.”

The calcium test for the heart uses a CT scan to take images of your coronary arteries, and the doctor is specifically checking for a buildup of calcium related to plaque in the vessels of your heart called coronary arteries.

A heart scan takes about 10 minutes to perform.

What Does A Heart Scan Score Measure?

A heart scan score measures the amount of plaque in your heart. This plaque in your blood vessels is different from the plaque your dentist finds on your teeth. It's a substance made up partly of fat and calcium. Plaque begins in the blood vessels in a waxy state and slowly builds up. As time passes, it can harden and calcify, a term referred to as "calcified" plaque.

"The plaque built up usually is a consequence of genetics along with known risk factors like high cholesterol, high blood pressure, diabetes, and smoking," said Ryan P. Daly, MD, a cardiologist at Franciscan Physician Network Indiana Heart Physicians who specializes in cardiac imaging. "The plaque over time gets worse if the factors are not controlled, and thus the calcium amount also grows. Sometimes we have had patients who have their calcium in the thousands of range when we measure it.

"The calcium score is more of a bird's eye view of what the coronary arteries look like. It does not indicate whether or not a patient has a blockage. The higher the number, the higher the patient's chances are of having a blockage."

What Does My Heart Score Number Mean?

A heart scan score ranges from zero to a few thousand. Generally speaking, the higher the heart scan score, the higher the amount of plaque in the heart, and the higher a person's risk of having a heart attack. 

“So the coronary arterial calcium score is pretty informative,” Dr. Lolay said. “Usually a score of zero is really good. It means that your risk of having events like heart attacks or strokes in the future is low. And then, the higher the score, the higher likelihood if you have in major events in the future. And so we use that score in order to modify or tailor the current medical plan.

“The score can vary from zero to few thousands, and obviously a score of zero is great, and the higher your score, the more concern and the higher likelihood of you having a major heart event or a stroke in the future.”

What Should I Do If My Heart Scan Score Is High?

If your heart scan score is high, your physician may recommend additional tests as well as work with you on preventive measures, including lifestyle changes and the use of statins, or cholesterol-lowering drugs.

"Aspirin and statins, along with lifestyle changes and diabetes control, are probably some of the only treatments we have to date that show that we can decrease heart attack risk in patients with elevated calcium scores," Dr. Daly said. "The treatment we have so far with medicine and lifestyle changes has been shown to decrease the risk of a heart attack in patients with elevated scores, but we have not yet proven whether or not the calcium in the arteries and the plaque in the arteries can be reversed all the way."

To decrease your chances of having a heart attack, Dr. Daly recommends focusing primarily on lifestyle choices.

"Heart disease is a direct consequence of what we eat, whether or not we exercise, and whether or not we live an active life," he explained. "My advice to my patients is always keep it simple. It comes down to eating healthier and exercising every day."

Who Should Have A Coronary Calcium Scan?

The American Heart Association suggests a coronary calcium scan is most useful for people ages 40 to 80 who have risk factors for coronary artery disease, such as:

• Current or former smoker
• Diabetes
• Family history of heart disease (parent or sibling)
• Abnormal cholesterol (such as high total cholesterol or low HDL)
• High blood pressure or are being treated for high blood pressure

If you have a sibling with an elevated calcium score, it may be a good idea for you to have a heart scan. However, the coronary calcium scan isn't for everyone. It involves exposure to radiation, roughly the same amount of exposure as a mammogram. It's wise to get a heart scan only if you know it can provide you with useful information. People younger than 40 with a strong family history of heart disease should discuss with their physician if calcium scoring is right for them.

Does My Insurance Cover Heart Scans?

It's also important to remember that health insurance usually doesn't cover heart scans. Check your insurance coverage and the cost before you get the test. A heart scan is not a substitute for stress testing and can tell you how blocked a coronary artery is, furthermore it does not detect any non-calcified plaque that may be present.