Coronary CT angiography lets you evaluate the composition of a plaque, not just its presence — a distinction that frequently changes management.
1
Calcified plaque
Appears bright white on CT (defined as ≥ 130 HU). Calcification is an active, regulated process — and calcified plaques tend to be the most stable, less prone to rupture.
2
Non-calcified (soft) plaque
Appears dark on CT. The riskiest category — much more prone to rupture.
Patients can harbor obstructive non-calcified plaque even with a calcium score of zero. This is especially relevant in younger patients, where plaque hasn’t had time to calcify.
3
Mixed plaque
Contains both calcified and non-calcified components within the same lesion. Report the mix — the non-calcified portion carries the rupture risk.