Prevalence and Extent of Coronary Artery Disease Determined by 64-Slice CTA in Patients With a Zero Coronary Calcium Score

This study addresses the most important limitation of coronary calcium scoring: a score of zero detects no calcified plaque, but soft, noncalcified plaque can still be present and dangerous.

Among 883 patients with a zero calcium score who underwent CT angiography, 20 percent had detectable coronary atherosclerosis and nearly 5 percent had obstructive disease — all invisible to calcium scoring alone. Age and diabetes most consistently flagged who harbored this hidden disease, with dyslipidemia predictive in men and family history in women.

The message refines, rather than refutes, the value of calcium scoring. Zero calcium is genuinely reassuring for most, but it is not an absolute “all-clear,” especially in symptomatic or high-risk patients — for whom CT angiography, which images the vessel wall directly, may still find disease worth treating.

We rate the evidence strong. It is a sizable, focused imaging study whose finding — that a meaningful minority with zero calcium still have plaque — is consistent with larger datasets (such as the SCAPIS population study) and clinically important for knowing the limits of the test.