Coronary Artery Calcium Score

A fast, non-contrast cardiac CT that quantifies calcified atherosclerotic plaque in the coronary arteries, producing an Agatston score that directly measures coronary artery disease burden and predicts cardiovascular event risk independently of standard blood markers. No contrast injection, no fasting, no preparation required.

The coronary artery calcium (CAC) score is a brief, non-invasive cardiac CT that measures the amount of calcified plaque in the walls of the three main coronary arteries. Unlike blood tests such as cholesterol or C-reactive protein, which indicate risk factors for heart disease, the CAC score directly measures the disease itself — the physical calcium deposits that form as atherosclerotic plaque hardens over time. This makes the CAC score one of the strongest independent predictors of future myocardial infarction available in clinical practice. At Hirslanden Klinik Im Park, the scan is acquired using ECG gating to eliminate cardiac motion artefact and is processed to calculate the Agatston score — a standardised measure of total coronary calcium burden. The scoring system stratifies risk into four tiers: a score of zero indicates no detectable calcification and carries an extremely low short-term cardiovascular event risk; 1 to 99 is mild; 100 to 399 is moderate; and 400 or above indicates severe coronary calcification and significantly elevated risk. A score of zero is particularly powerful: in large prospective studies, zero-CAC patients have a cardiovascular event rate of approximately 1% over 10 years even when standard risk scores suggest intermediate risk, and this finding can justify deferring or discontinuing statin therapy in appropriate patients. Conversely, a high score prompts intensification of lifestyle and medical management even when LDL cholesterol appears acceptable. The examination requires no contrast injection, no intravenous access, no fasting, and no preparation beyond avoiding caffeine before the scan. Total time at the cardiovascular centre is approximately 20 to 30 minutes. The cardiologist report includes the Agatston score with per-vessel breakdown, age- and sex-specific risk percentile ranking, and a clinical recommendation. The CAC score is often used as a first-line cardiovascular screening test and as a triage tool to decide whether full coronary CT angiography with contrast is warranted. It is available to self-pay patients and those with Swiss complementary health insurance.