Calcium Score vs CTCA: Which Heart Test Do You Actually Need?
- Dr Chan Po Fun
- Aug 10
- 5 min read
Updated: Aug 17
Dr Chan Po Fun [MBBS, MRCP, FRCP (UK), FAMS (Cardiology)] is a consultant cardiologist in Singapore with a focused practice in cardiovascular risk across life stages.
If you've been told to get a "heart screening" in Singapore, you've probably come across two very different tests that sound confusingly similar: the calcium score vs CTCA (coronary angiogram). Patients often assume they're interchangeable, or that the more expensive, more detailed scan must be the "better" one.
They're not interchangeable. They answer different questions, for different patients. Getting the wrong one means paying more, absorbing more radiation, or getting an answer that never actually needed to be asked.
Here's how to tell which one is right for you.
What Is a CT Calcium Score?
A CT calcium score (also called a coronary artery calcium, or CAC, score) is a quick, low-dose CT scan that measures how much calcified plaque has built up in your coronary artery walls. No contrast dye, no injection, no special preparation.
It doesn't show whether an artery is narrowed or blocked. What it gives you is a number (your calcium score) that reflects your cumulative, long-term burden of atherosclerosis. That number is one of the most powerful tools we have for refining cardiovascular risk in someone who currently has no symptoms.
What Is a CTCA (CT Coronary Angiogram)?
A CTCA uses the same CT scanner, but with an intravenous contrast dye injection, a higher radiation dose, and a different purpose: it images the inside of the artery itself, showing narrowing, blockages, and soft (non-calcified) plaque that a calcium score cannot detect.
A CTCA is a diagnostic test. It's generally used when someone has symptoms (chest pain, breathlessness, an abnormal stress test) or when a calcium score result needs more clarity.
Calcium Score vs CTCA at a Glance
CT Calcium Score | CTCA | |
Best for | No symptoms, risk assessment | Symptoms, or diagnostic clarity |
Shows | Calcium burden (a risk marker) | Actual narrowing and blockages |
Contrast dye | Not needed | Required |
Radiation | Very low | Low, but higher than calcium score |
Can a "normal" result still miss disease? | Yes. Soft, non-calcified plaque isn't visible | Rarely. It images the artery directly |
Typical role | Prevention and statin-decision tool | Diagnosis |
What Your Calcium Score Number Actually Means
This is the part that most general explainers skip, and it's the part that changes management. Under the framework used in the current dyslipidemia guidelines, your calcium score doesn't just get filed away. It should change what happens next:
Score of 0: Reassuring for most people. Focus stays on lifestyle; statins are often not urgent unless you have other strong risk factors (such as a markedly elevated Lp(a) or a strong family history).
Score 1–99: Low but present. Whether to start a statin becomes an individual decision, particularly if you're over 55.
Score 100–399: Statin therapy is generally indicated, alongside tighter blood pressure and blood sugar control. If you have symptoms at this level, a CTCA is often the next step.
Score 400–999: Treated as high-risk. This usually means more intensive risk-factor management across the board.
Score ≥1,000: Very high-risk. This typically calls for aggressive LDL-lowering, sometimes beyond statins alone.
In other words: the calcium score isn't a pass/fail test. It's a number that should directly shape your treatment plan, which is why the result is best reviewed with a cardiologist rather than read off a lab report alone.
So Which Test Do You Need?
As a general guide:
No symptoms, checking your baseline risk → calcium score is almost always the right starting point.
Chest pain, breathlessness, or an abnormal stress test → a calcium score alone isn't enough. This calls for a CTCA or equivalent diagnostic workup, and a calcium score of 0 should not be used to wave away symptoms.
Borderline cholesterol and unsure if you need a statin → a calcium score is often the tie-breaker your GP or cardiologist needs.
Strong family history, very high Lp(a), or an inconclusive calcium score → this is where a CTCA may add real value, even without classic symptoms.
Still not sure which column you fall into?
A Note for Women
Cardiovascular risk calculators and calcium scores were validated on populations that skewed male, and calcium tends to build up later in women than men. This means a low calcium score in a woman, particularly a younger or perimenopausal woman, doesn't always tell the full story the way it might in a man of the same age.
Risk factors like early menopause, pregnancy complications (pre-eclampsia, gestational diabetes), and autoimmune disease matter more in this decision than most standard checklists account for.
This is worth discussing directly with your doctor rather than assuming your result means the same thing it would for your husband or father.
What About Cost?
As a general guide in Singapore's private sector: a stand-alone calcium score typically is cheaper than a CTCA (usually inclusive of a calcium score).
Both require a doctor's referral by local regulation, and MediSave can be used (up to the annual CT scan limit) where the scan qualifies. Exact pricing depends on the facility and scanner used. During your consultation, we'll confirm current pricing before you commit to anything.
Want a straight answer on cost?
About Dr Chan Po Fun
Dr Chan Po Fun is a consultant cardiologist in Singapore who sub-specialises in advanced cardiac imaging, including CT coronary calcium scoring and CT coronary angiography (CTCA).
Consultations are available at Gleneagles Hospital and Mount Alvernia Hospital. No referral is required.
Frequently Asked Questions
Is a calcium score included in a CTCA?
Usually, yes. Most CTCA protocols include a calcium score as part of the same scan.
Can I go straight for a CTCA without a calcium score first?
Sometimes, but it's not the default. If you have no symptoms, starting with a calcium score avoids unnecessary contrast exposure and radiation. If you have symptoms, your doctor may recommend proceeding straight to CTCA.
I have a calcium score of 0. Does that mean my arteries are completely clear?
Not necessarily. A score of 0 is reassuring and lowers your near-term risk substantially, but it doesn't rule out soft, non-calcified plaque, which is why it shouldn't be used to dismiss genuine symptoms.
Do I need a referral for either test?
Yes, both require a doctor's referral in Singapore. A consultation lets us confirm which test actually answers your specific question, rather than defaulting to the most expensive option.
How much radiation am I exposed to?
A calcium score uses a very low dose, comparable to a small fraction of background annual radiation exposure. A CTCA uses more, though still within a range considered safe when clinically indicated.
The Test Should Answer a Question, Not Just Produce a Number
More testing isn't automatically better testing. The right scan is the one that changes what we do next for your specific risk profile, which is why we start with a consultation, not a fixed package.
Not sure which one applies to you? WhatsApp us or book a consultation and we'll help you work it out.
Related reading: Heart Screening in Singapore: Which Test Do You Actually Need? · Cholesterol Management · Women's Heart Health · Longevity
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