Can this test save your life?

Coronary artery disease is the leading cause of death in the United States and the world. It results in heart attacks, angina, congestive heart failure, and even sudden death. Unfortunately, coronary artery disease usually cannot be diagnosed by a doctor in an office without additional testing. And traditional tests for it are often expensive, time-consuming, and invasive. Wouldn’t it be nice if there was a simple, inexpensive, non-invasive test that could tell you if you had coronary artery disease?

Well, it turns out there is such a test – but, unfortunately, it is not as widely used as it could be. This test is called a coronary calcium score, and it can diagnose coronary artery disease.

What is a coronary calcium score?

Coronary – Although the heart fills with blood and pumps it, the heart muscle is too thick to be nourished just from the inside.  Coronary arteries are the vessels that supply the heart muscle with the oxygen and nutrients it needs to squeeze. When these arteries become blocked, it causes a heart attack.

Calcium – As cholesterol plaques develop in coronary arteries, calcium can deposit in them.  Calcium is very good at blocking x-rays – that’s why bones and teeth show up so well on x-ray images.

Score – CT scans are basically very fancy x-ray machines that can give very detailed images.  Because calcium shows up so well on them, a CT scan of the heart can be used to determine how much calcium is in the coronary arteries, giving a numerical value – the “coronary calcium score”.

The amount of radiation that you receive from this test is much lower than with a conventional CT scan which might be used to look at the lungs or other internal organs.  With modern techniques and scanners, the amount of radiation is similar to that of a mammogram. Additionally, a coronary calcium score does not require any IV dye, and unlike an MRI, it only takes a few seconds.

Why is a coronary calcium score helpful?

I often say that your cholesterol profile is a reflection of who you are.  A coronary calcium score is even better – it is a reflection of who you have been.  All of the things that can potentially contribute to coronary artery disease – cholesterol, blood pressure, genetics, etc. – totaled over your lifetime will result in the accumulation of coronary calcium, which we can now easily detect and measure.

“Your cholesterol profile is a reflection of who you are. A calcium score is even better – it is a reflection of who you have been.”

– Doctor T

The risk calculators we currently use are not particularly comprehensive. If you look at the calculators mentioned in our article on risk assessment, some of them incorporate race, family history, and CRP, but none of them incorporate them all.  None of them ask about well known risk factors such as gout, early menopause, or erectile dysfunction. Coronary calcium scoring is valuable, because instead of trying to predict disease based on risk factors, it detects and measures the actual disease.

Multiple studies have shown that the amount of calcium in your coronary arteries predicts your risk of having a heart attack.  A score of zero is very reassuring, while very high scores (greater than 400) indicate a high burden of coronary artery disease and a high risk.

Essentially, coronary calcium scores can be used to enhance risk assessment. If standard prediction models show that you have a moderately elevated cardiac risk, but you have no calcium in your coronary arteries (a score of 0), your risk may not be as high as expected, and you may not benefit as much from a statin medication. Similarly, if you have a relatively low calculated risk, but you have more calcium in your arteries than expected, you may benefit from a statin.

Coronary calcium scores are not helpful for everyone.  If your 10-year risk by traditional calculators is approaching 20 percent or higher, you are likely to have a score greater than zero, which would not change management. If you are younger than 40, you may have falsely reassuring scores because you may not have yet developed coronary artery disease (or you may have developed coronary artery disease that has not yet calcified).  Your lifetime risk may still be elevated, and risk factors should still be addressed.

Our article on the new cholesterol guidelines also talks about who may benefit from a coronary calcium score. Those guidelines specifically discuss patients with a 10-year ASCVD risk between 5 and 7.5% and people over the age of 75. Other people who may benefit are those with a higher ASCVD risk – between 7.5% and 20% – who are unsure of whether they should be on a statin after discussion with their physician.

How do I get a coronary calcium score?

Speak to your doctor about whether it is right for you. Be aware that despite the benefits of the test, most insurance companies will not yet pay for coronary calcium scoring.  Fortunately, many hospitals offer the test for a reasonable price – often around $100.