No obstructive CAD — still plaque

One of the most confusing CCTA sentences is: “No obstructive coronary artery disease” followed by a description of plaque. Those two ideas can both be true. This page explains the distinction. It is educational. It is not a reading of your study. Talk with your doctor.

Obstruction vs plaque

Obstructive (in this setting) refers to a narrowing of the channel the blood flows through — the lumen — that the reader thinks is in a severe or flow-limiting range. Different labs use different cutoffs; many talk about 70% (or 50% in the left main) as a ballpark for “obstructive,” but CT percentages are estimates.

Plaque is material in the artery wall. It can be calcified, noncalcified, or mixed. Plaque can exist with a lumen that is still wide enough that the reader does not call the lesion obstructive. The wall can be diseased while the opening looks adequate on that scan.

So “no obstructive CAD” is not always a synonym for “normal coronary arteries.” If the report also says mild plaque, atherosclerosis, or CAD-RADS 1 or 2, that is information about prevention — not a reason to ignore the study, and not a reason to panic.

Why this matters for medicines and follow-up

A cath-era habit was to treat “no stent-level lesion” as a finish line. CCTA made wall plaque visible in people who never went to the cath lab. Many clinicians use that information to talk about:

• Statins or other lipid-lowering therapy
• Blood pressure, diabetes, smoking, and exercise
• Whether symptoms still need a stress test or another look
• When (or whether) to image again — which is not a routine annual CT

None of those bullets is a prescription from this website. The point is: a non-obstructive report can still change a prevention plan. Ask your clinician explicitly, “Do I have plaque, and does that change my medicines?”

CAD-RADS 1–3, in one paragraph

CAD-RADS categories in the mild-to-moderate range are exactly the zone where plaque is present and a severe stenosis is not (or is only moderate). That zone is also the range often discussed when people talk about AI plaque analysis after a CCTA — including the CPT 75577 path as of 2026-01-01. Medicare and other payers typically consider that add-on, when they consider it at all, after an indicated CCTA with findings in a non-severe range. That is not automatic coverage. See Insurance, Medicare, and CPT 75577. We do not claim your plan will pay for plaque software.

What “normal” would look like

Some reports say no plaque and no stenosis (sometimes CAD-RADS 0). That is the closest CT comes to “clear arteries” — and it still is not a lifetime guarantee. People can develop plaque later. Symptoms that persist still need a clinician, because chest pain has causes other than coronary blockage.

What to do with your report

• Read the impression with the glossary nearby
• Note every vessel that mentions plaque, even “mild”
• Ask who manages prevention from here (PCP, cardiology, both)
• Do not start or stop a medicine based on this article
• Do not assume you need a cath because plaque was mentioned, or that you need nothing because stenosis was not severe

CCTA Scan does not interpret your pictures. We list where CPT 75574 was billed to Medicare FFS in 2024. If you are looking for a site for a future, ordered exam, start at Find a CCTA or San Diego and West Hollywood.

This article is educational and is not medical advice. Talk with your doctor.