Coronary Artery Disease Scores

CACS-CL Calculator – Coronary Calcium and CAD Clinical Likelihood

Clinical calculation support · Verify results before clinical use

Clinical likelihood assessment

Estimate the likelihood of obstructive coronary artery disease in adults with suspected chronic coronary syndrome.

—CACS-CL

Patient characteristics

Model age range: 30–80 years.

Age (years)Enter a whole number from 30 to 80.

Sex

Symptoms

Select the main symptom and applicable chest pain characteristics. The symptom score is 0–3.

Chest pain characteristics

Constricting discomfort located retrosternally or in the neck, jaw, shoulder, or arm (1 point) Aggravated by physical or emotional stress (1 point) Relieved by rest or nitrates within 5 minutes (1 point) Exertional dyspnoea as a main symptom (2 points)

The main symptom is chest pain (0–3 points) or dyspnoea (2 points). When both are present, the ESC symptom-score algorithm is applied.

Coronary artery disease risk factors

Count each present risk factor once (0–5).

Family history of premature CAD in a first-degree relative (men <55; women <65 years) Current or past smoking Dyslipidaemia Hypertension Diabetes mellitus

Coronary artery calcium score

Enter the Agatston score from an ECG-gated, non-contrast cardiac CT.

Coronary artery calcium score (Agatston units)Non-negative whole number. Do not enter a percentile.

CAC measurement sourceThe numeric CACS-CL equation requires an Agatston score. A qualitative incidental CAC finding cannot be entered as a numeric score.

—Likelihood

CACS-weighted clinical likelihood of obstructive CAD

Awaiting inputs

Complete all required fields to calculate RF-CL and CACS-CL.

RF-CL estimate—

CAC category—

Symptom score—

Number of risk factors—

Clinical interpretation

This calculator estimates the likelihood of obstructive epicardial CAD; it does not diagnose CAD or myocardial ischaemia.

CACS-CL is a pre-test likelihood estimate. Interpret it with symptoms, examination, ECG, echocardiography, comorbidities, and clinical judgement.

About the CACS-CL model

The Coronary Artery Calcium Score-weighted Clinical Likelihood (CACS-CL) model combines the risk factor-weighted clinical likelihood (RF-CL) estimate with coronary artery calcium score to estimate the likelihood of obstructive coronary artery disease in symptomatic patients being evaluated for chronic coronary syndromes.

Model inputs

Age and sex.
Chest pain characteristics or exertional dyspnoea.
Five risk factors: premature family history of CAD, current or past smoking, dyslipidaemia, hypertension, and diabetes.
Agatston coronary artery calcium score, grouped as 0, 1–9, 10–99, 100–399, 400–999, or ≥1000.

Likelihood categories

Likelihood	Estimated probability	General diagnostic pathway
Very low	≤5%	Further testing may often be deferred, subject to clinical context.
Low	>5–15%	Consider additional assessment; CACS may help reclassify likelihood.
Moderate	>15–50%	Non-invasive anatomical or functional testing is generally considered.
High	>50–85%	Further diagnostic evaluation is generally indicated.
Very high	>85%	Consider invasive coronary angiography in the appropriate clinical context.

Important model limitations

Designed for symptomatic adults with suspected chronic coronary syndrome, not acute coronary syndrome, screening of asymptomatic individuals, or patients with established obstructive CAD.
The derivation model used coronary CTA to define obstructive CAD as ≥50% diameter stenosis.
RF-CL does not include every condition that may increase CAD likelihood. Familial hypercholesterolaemia, severe renal dysfunction, inflammatory/rheumatic disease, and peripheral artery disease may require individual clinical adjustment.
A CACS of zero does not exclude non-calcified plaque or all obstructive CAD, particularly in younger patients.
The model estimates obstructive epicardial CAD likelihood; it does not estimate myocardial ischaemia or the likelihood of ANOCA/INOCA.

References

Winther S, Schmidt SE, Mayrhofer T, et al.Incorporating Coronary Calcification Into Pre-Test Assessment of the Likelihood of Coronary Artery Disease. J Am Coll Cardiol. 2020;76(21):2421–2432. doi:10.1016/j.jacc.2020.09.585

Vrints C, Andreotti F, Koskinas KC, et al.2024 ESC Guidelines for the management of chronic coronary syndromes. Eur Heart J. 2024;45(36):3415–3537. doi:10.1093/eurheartj/ehae177

Winther S, Schmidt SE, Foldyna B, et al.Coronary Calcium Scoring Improves Risk Prediction in Patients with Suspected Obstructive Coronary Artery Disease. J Am Coll Cardiol. 2022;80(21):1965–1977. doi:10.1016/j.jacc.2022.08.805

Brix GS, Rasmussen LD, Rohde PD, et al.Calcium Scoring Improves Clinical Management in Patients With Low Clinical Likelihood of Coronary Artery Disease. JACC Cardiovasc Imaging. 2024;17(6):625–639. doi:10.1016/j.jcmg.2023.11.008

Clinical disclaimer: This educational calculator supports, but does not replace, clinical assessment. Do not use it to evaluate acute chest pain or suspected acute coronary syndrome. A low calculated likelihood must not override high-risk symptoms, haemodynamic instability, abnormal ECG/troponin findings, significant ventricular dysfunction, or other concerning clinical features. Diagnostic decisions should follow current guidelines and local pathways.