Why it matters
Risk calculators estimate. A calcium score measures.
Conventional cardiovascular risk assessment relies on age, blood pressure, cholesterol, smoking status, and family history. The widely-used QRISK calculator in the UK and the newer PREVENT equations from the United States estimate risk reasonably well across populations, but they can be wide of the mark for individuals.
Some patients classified as "low risk" already have advanced atherosclerosis. Others carry several risk factors but anatomically clean arteries. A coronary artery calcium (CAC) scan replaces estimation with direct visualisation: it quantifies the calcified component of plaque in the coronary arteries, expressed as an Agatston score. The presence and extent of calcification correlate strongly with the risk of future cardiovascular events.
Calcium scoring is supported as an option for refining cardiovascular risk assessment in the 2026 ACC/AHA guideline on the management of dyslipidaemia. For patients on the fence about lifelong statin therapy, the score acts as a tiebreaker — replacing a population estimate with a direct measurement of disease in your own arteries.
The score doesn't predict your future. It describes the disease that has already occurred — quietly, over decades — and tells us how much room there is to change the trajectory.
The scan itself
Ten minutes. No needles, no contrast, no preparation.
The scan uses an ECG-gated CT scanner and is over within minutes of you lying down. There is no intravenous line, no contrast dye, and no claustrophobic enclosure. Radiation exposure is approximately 1 millisievert — comparable to a mammogram, and lower than many conventional cardiac investigations.
The result, an Agatston score, is available the same day. The clinical interpretation — placing that number alongside your blood results, family history, lifestyle, and preferences — happens in the consultation that follows.
Duration
~10 minutes
Radiation
~1 mSv
Preparation
None required
Result
Same day
Interpreting the result
What the number means.
The bands below reflect the 2026 American College of Cardiology guideline on the management of dyslipidaemia, which formalised calcium-stratified treatment targets for the first time. The score informs, but does not dictate, the conversation that follows.
Suitability
A calcium scan helps most when the decision is genuinely in the balance.
Likely to benefit
- Men aged 40 and over and women aged 45 and over with intermediate cardiovascular risk where the case for statin therapy is uncertain
- A family history of premature coronary disease (heart attack in a first-degree relative under 55 in men, 65 in women)
- Borderline cholesterol with reluctance to start lifelong therapy without clearer evidence of risk
- Existing risk factors but a wish for a more personalised assessment than population calculators offer
Not appropriate for
- Familial hypercholesterolaemia or LDL-C ≥ 4.9 mmol/L — statin therapy is indicated regardless of the score
- Established coronary artery disease, previous heart attack, or prior stenting
- Symptoms suggestive of angina — these warrant a different investigation pathway, usually a CT coronary angiogram or stress test
- Adults under 40, in whom the absence of calcium is less reassuring than in older patients
After the scan
The number is the beginning of the conversation, not the end.
Every result is reviewed in consultation. The score is interpreted alongside your blood lipids, blood pressure, family history, and preferences, and translated into a clear plan: lifestyle, lipid-lowering therapy at a proportionate intensity, and a sensible interval for review. The aim is informed prevention rather than reflexive treatment.
For some patients, the appropriate response will be reassurance and lifestyle reinforcement. For others, it will be the early start of preventive therapy that may, over decades, prove decisive. The point of the scan is to make that distinction visible.
Honest limitations
What the score doesn't tell us.
Calcium scoring detects calcified plaque. It is less sensitive to the softer, non-calcified plaque that can also be clinically important, particularly in younger patients and those with inflammatory conditions or diabetes. In adults under 40, the absence of calcium is less reassuring than it is later in life.
The score is a single point in time and does not replace ongoing cardiovascular review. Once lipid-lowering therapy is started, the score should not be repeated to monitor response — statins increase calcified plaque even as they stabilise it, which makes serial scoring unhelpful. Response is monitored through cholesterol levels instead.
Like any chest CT, the scan can occasionally identify findings outside the heart — most commonly a small lung nodule. Most are benign and resolve with routine follow-up, but they can lead to additional investigations. Where this happens, we discuss the finding and its significance in context.
Fees and access
Two fees apply.
Coronary calcium scoring at Spire Bristol Hospital involves two separate fees: a fee for the CT scan itself, paid to Spire, and a separate consultation fee for the review and clinical interpretation with Dr Aziz. Current rates are available from Rachel Peacock or directly from Spire bookings — please contact us before booking to confirm.
No GP referral is required. Self-pay patients can book directly. A referral letter or recent investigation results are helpful where available, but not necessary.
Calcium scoring is offered as part of Dr Aziz's private cardiology consultations at Spire Bristol Hospital. If a calcium scan is one of several investigations being considered, it is often more straightforward to arrange a consultation first to agree the right pathway for your individual circumstances.