The coronary calcium score, explained

A coronary calcium score is one of the most useful heart tests most people have never heard of. It is a low-dose CT scan of the heart, no injection and no treadmill, that looks for calcified plaque in the arteries that feed the heart muscle.

Calcium in those arteries is a sign of furring, the process behind most heart attacks, and the scan turns that into a single number. A score of zero means no calcified plaque was found, which is reassuring and places you at low near-term risk. A higher score means more plaque, and the number tracks with how much, from a little to a lot.

Where it earns its keep is the in-between. Plenty of people sit in a grey zone on a risk calculator, not clearly low risk and not clearly high, and a calcium score settles the question. A zero can spare someone years of medication they did not need; a high score can be the nudge to take prevention seriously while there is time to act. It is most useful from the forties onward, or earlier with a strong family history.

It has limits. It measures calcified plaque, and early soft plaque does not show up, so a zero is reassuring rather than a guarantee. And it tells you about risk, not about symptoms; chest pain that comes on with effort is a different question that points to other tests.

This is an add-on rather than part of every heart check, because not everyone needs it. If your question is whether to take your heart risk seriously, the calcium score often answers it cleanly, and we will tell you whether it is the right test for you.

Ready to start? Choose the check that fits your question and tell us a little about yourself. A doctor reviews it, arranges what you need, and explains what it means. Most of it is done online, with the clinic there if you would rather be seen.