Coronary calcium score
A quick CT scan that shows whether calcified plaque has already built up in the arteries of your heart.
TypeImaging — non-contrast CT scan
HowLie on a scanner for about 10 minutes. No needles or dye; low radiation dose.
How oftenOften once. If your score is 0, a repeat may be considered after several years.
BeforeAvoid caffeine and smoking for about 4 hours before. Wear clothes without metal.
WhoTypically adults 40–75 whose heart risk is borderline or unclear.
A direct look at plaque in your arteries
Most heart tests estimate risk from numbers in your blood. A calcium score looks at the arteries themselves - calcium is a marker of plaque that has built up over years.
Risk calculators
“What’s my estimated risk?”
Based on age, cholesterol, blood pressure and smoking - an average for people like you.
Estimate
Calcium score
“Do I already have plaque?”
Shows whether plaque is present and how much - in your arteries, not an average.
Evidence
How a calcium score is used
01
Zero isn’t a free pass
Early, soft plaque has no calcium yet. Keep managing risk factors.
02
Any calcium matters
It means plaque is present - and often changes the treatment plan.
03
Don’t repeat too often
Scores change slowly. Repeat only if it would change your plan.
04
Pair with blood tests
Plaque shows the past. ApoB and Lp(a) show what’s driving it.
Is it right for you?
Worth considering if…
- You’re 40+ and unsure whether to start or step up cholesterol treatment.
- Heart disease runs in your family.
- Your risk score comes back borderline or intermediate.
- Your ApoB or Lp(a) is high and you want to know whether it has caused plaque.
A better option if…
- You’re under 40 with no strong risk - scores are usually 0. Start with ApoB and Lp(a).
- You have chest pain or other symptoms - see your provider; a different test may be needed.
- You already have known heart disease - this scan rarely changes the plan.
How it’s measured
Non-contrast cardiac CT
The standard CAC scan. Quick, no injection, low radiation.
Reported as a score + percentile
Your score, plus how it compares with people of your age and sex.
The full picture
What is it?
A CT scan that detects calcium in the walls of the coronary arteries - a sign that plaque has formed.
What type of test is it?
An imaging and risk-assessment test.
What does it measure?
The amount and density of calcified plaque, reported as an Agatston score and an age/sex percentile.
Why might someone consider it?
It shows plaque directly, instead of estimating risk. That can help decide whether cholesterol treatment makes sense.
Who is it most relevant for?
Adults roughly 40–75 with borderline or intermediate risk, or a strong family history, where the result would change a decision.
How is it performed?
You lie on a CT table while it takes images timed to your heartbeat. It takes minutes.
How often might it be considered?
Usually once. With a score of 0, a repeat may be considered after several years; with a high score, repeating rarely helps.
What can the result help you understand?
Whether plaque is present and how much - which can move your risk up or down from what bloodwork alone suggests.
What are its limitations?
It only sees calcified plaque, not soft plaque. A 0 can be falsely reassuring in younger people or smokers. It involves some radiation, can find incidental issues (like lung nodules) that lead to more tests, and is often self-pay.
What should it be viewed with?
ApoB, LDL, Lp(a), hs-CRP, blood pressure, blood sugar, smoking history and family history.
Where to get it
Through your provider
A referral to radiology or a hospital heart centre.
Imaging centres
Many offer self-referral for CAC scans.
Hospital heart programmes
Often bundle the scan with a consultation.
Names are examples only, not endorsements. Your provider can often order the same test - and help interpret it.
Connected to
Questions to ask your provider
- Would a calcium score change my treatment decisions?
- Am I in the age and risk range where it’s useful?
- If my score is 0, when - if ever - should I repeat it?
- What happens if the scan finds something else?
Ziva Health
One test is a snapshot. Ziva shows the whole story.
Ziva brings your lab results, wearables and daily readings together - and Isabella tells you what’s changing and what to ask your provider next.
Refer Ziva to my provider / care team
Is your provider not on Ziva yet? Send them a link in under a minute - once they join, they’ll see your Coronary calcium score result alongside your other trends and get alerts directly.
Refer my providerAlready seeing your provider?
Bring your Ziva 30-day report to your next appointment - your Coronary calcium score result and daily trends in one view, so the conversation starts with the full picture.
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Being listed doesn’t mean everyone needs this test. Educational only — not medical advice. Results should be interpreted with a qualified clinician. ← Back to Know What to Test