What is the patient presentation? *

Acute chest pain Stable chest pain

What is the maximal degree of stenosis among interpretable coronary segments? *

Grade the most clinically relevant stenosis on a per-patient basis in coronary segments greater than 1.5 mm in diameter. For bypass grafts, apply CAD-RADS graft rules.

Is the 50–69% stenosis in the left main coronary artery? *

Left main stenosis ≥50% is CAD-RADS 4B.

Yes No

Which severe stenosis pattern is present? *

One or two vessels with 70–99% stenosis, without left main stenosis ≥50% Left main stenosis ≥50% and/or three-vessel severe obstructive disease (≥70% in all 3 major epicardial vessels)

Are any coronary segments >1.5 mm non-diagnostic such that obstructive stenosis cannot be excluded? *

If all diagnostic segments are <50% stenosed, a non-diagnostic segment changes the category to CAD-RADS N. If a diagnostic segment has ≥50% stenosis, retain the numeric category and add modifier N.

Yes No

What is the overall coronary atherosclerotic plaque burden? *

If plaque-burden methods disagree, use CAC or validated quantitative total plaque burden when available; otherwise use the method selected by your institution and state the method used.

No atherosclerotic plaque P1 — Mild: CAC 1–100; SIS ≤2; or mild plaque in 1–2 vessels P2 — Moderate: CAC 101–300; SIS 3–4; or moderate plaque in 1–2 vessels / mild plaque in 3 vessels P3 — Severe: CAC 301–999; SIS 5–7; or moderate plaque in 3 vessels / severe plaque in 1 vessel P4 — Extensive: CAC ≥1000; SIS ≥8; or severe plaque in 2–3 vessels Plaque is present, but burden cannot be reliably categorized

Does a coronary plaque demonstrate at least two high-risk plaque features? *

High-risk features: spotty calcification, low-attenuation plaque <30 HU, positive remodeling, and napkin-ring sign. Two or more features in a plaque are required for HRP.

Yes — add HRP modifier No

Was a CT-based ischemia assessment performed? *

Neither CT-FFR nor stress CTP CT fractional-flow-reserve (CT-FFR) Stress myocardial CT perfusion (CTP)

What is the lesion-specific CT-FFR result? *

Use the lesion-specific CT-FFR value approximately 1–2 cm distal to the stenosis and interpret it with the anatomic lesion. The lowest value anywhere in the vessel should not by itself guide catheterization referral.

Negative for lesion-specific ischemia: >0.80, or confidently interpreted as non-ischemic despite a distal pressure decline — I− Borderline or indeterminate for lesion-specific ischemia: 0.76–0.80 or discordant with the anatomic lesion — I± Positive for lesion-specific ischemia: ≤0.75 with a concordant anatomic lesion — I+ CT-FFR is non-diagnostic — N

What is the stress CTP result? *

No reversible ischemia or fixed prior myocardial infarction — I− Borderline, discordant, or inconclusive for ischemia — I± Reversible myocardial ischemia or peri-infarct ischemia — I+ Stress CTP is non-diagnostic — N

Is at least one coronary stent present? *

In-stent stenosis is graded using the same stenosis categories as native coronary arteries.

Yes — add S modifier No

Is at least one coronary bypass graft present? *

A native stenosis bypassed by a fully patent graft is not used for the stenosis category. Assess plaque burden across native coronaries and grafts.

Yes — add G modifier No

Is a non-atherosclerotic coronary abnormality present? *

Examples include coronary dissection, anomalous origin, aneurysm or pseudoaneurysm, vasculitis, fistula, extrinsic compression, and arteriovenous malformation.

Yes — add E modifier No