It sees what the calcium score can't. A calcium score is the same machine without contrast, and it only picks up plaque that has already hardened — often decades old. Add contrast and the scan lights up the lumen, the actual channel blood flows through, plus the soft plaque that ruptures first and starts the clot ¹.

The payoff is prevention, not surgery. The 41% drop came from doctors starting statins and antiplatelets earlier on the strength of what the scan showed, with no extra stenting ². The 10-year follow-up held the gain ³. An abnormal scan almost never means a stent; stable disease is treated with medicine first ⁴.

Any plaque counts. Even non-obstructive plaque, the kind too small to pinch the artery, roughly doubles your 10-year heart-attack risk versus clean arteries ⁵. It is now the first-line test for stable chest pain in the US, European, and UK guidelines ^{6 7}.

This is a test you ask for, not one you show up and buy. Bring these to your GP or a cardiologist.

The scan itself is a quiet morning; the follow-up is the intervention.

• Same week: nothing changes. You go home and wait a few days for the report.
• Clean scan: obstructive disease is ruled out for years, and the cardiac worry closes.
• Plaque found: a high-intensity statin starts, blood pressure gets a tighter target, and the family conversation gets serious.
• Five years on: the SCOT-HEART trajectory puts your heart-attack odds near half of what they were ².

Radiation runs about 2.7 millisieverts on modern scanners — roughly nine months of ordinary background exposure, and under 1 on the best machines ⁸. US cash prices run $500–$2,000; in the UK and much of Europe it is publicly funded under the chest-pain pathway.