Carotid Stenosis: What It Actually Means for Your Stroke Risk

In short: Finding plaque or a narrowing in your carotid artery can be unsettling, especially with a high percentage on the report. But that number alone doesn’t tell you whether a stroke is coming or whether you need an operation. What matters most is whether you’ve had warning symptoms, what the plaque itself looks like, and how much a procedure would realistically add on top of strong medical treatment. A major trial, CREST-2, has reshaped that last question for people without symptoms — and the answer is more nuanced than most people expect.

You Found Out You Have Carotid Plaque — Now What?

It usually starts the same way: a routine checkup, a scan ordered for something else, or a doctor who heard something during a neck exam. Then the report comes back with a phrase you weren’t expecting — carotid plaque, or carotid stenosis, sometimes with a percentage attached.

Plaque is a buildup of fatty and inflammatory material inside the artery wall. When it narrows the space through which blood flows, doctors call it carotid stenosis.

Plaque often develops gradually over many years, sometimes without causing any symptoms. Finding it doesn’t necessarily mean something dangerous is happening right now. But it does mean there’s an important cardiovascular risk factor worth understanding and addressing.

Does This Mean You’re Going to Have a Stroke?

Not necessarily — and it depends on more than the percentage alone.

The single biggest factor is whether you’ve actually had symptoms caused by that artery.

If you develop sudden weakness on one side, trouble speaking, a drooping face, or temporary loss of vision in one eye — even if it lasts only a few minutes — seek emergency medical care immediately. These symptoms can be warning signs of a transient ischemic attack (TIA, sometimes called a mini-stroke) or stroke and require emergency evaluation, even if they disappear.

That situation is handled differently from everything below.

What this article focuses on is another common situation: no symptoms at all. The narrowing was found incidentally, on a scan done for something unrelated. Doctors call this asymptomatic carotid stenosis — and it requires a different assessment from a narrowing that has already caused neurological symptoms.

Why the Percentage on Your Report Isn’t the Whole Story

Two people can have the same 70% narrowing and carry very different risks.

What the plaque looks like under ultrasound — not just how much it narrows the artery — can provide additional information. Some plaques appear more stable, while others have features associated with a greater chance of releasing tiny particles that can travel toward the brain.

Specialized tests can sometimes detect signs of this process, though they aren’t used for everyone and can’t predict exactly what will happen to any one person.

Your symptoms, age, other medical conditions, and overall cardiovascular risk also matter.

The takeaway isn’t that the percentage is meaningless. It’s that the percentage is where the conversation starts, not where it ends.

What Actually Gets Decided, and How

Whatever the percentage, one part of treatment applies to nearly everyone with carotid atherosclerosis: controlling the disease itself, not just the one narrowed artery.

Carotid plaque is a sign of atherosclerosis, the same process that affects arteries in the heart and elsewhere.

That means managing cholesterol, often with statins; controlling blood pressure and diabetes; quitting smoking if applicable; and maintaining healthy lifestyle habits. Depending on your individual situation, your doctor may also recommend an antiplatelet medication, such as aspirin, which helps prevent platelets from forming certain blood clots.

This isn’t the fallback when surgery isn’t an option. It’s the foundation, whether or not a procedure ever happens.

On top of that foundation, two established procedures exist: an operation that physically removes the plaque (carotid endarterectomy), or a catheter-based procedure that places a small mesh tube inside the artery to keep it open (carotid stenting).

For selected people who’ve recently had symptoms caused by a significantly narrowed artery, the evidence for intervention is strong, and timing matters. When surgery is appropriate after a TIA or minor stroke, doctors often aim to perform it within about two weeks, because the risk of another event can be highest early on.

For people who’ve never had symptoms, it’s a different calculation.

A severe narrowing doesn’t automatically mean you need a procedure. The real question is whether adding one meaningfully lowers your risk beyond what strong medical treatment already achieves.

What Changed: The CREST-2 Trial

For a long time, that question didn’t have a clear modern answer.

CREST-2 tested it directly: in people with severe carotid narrowing of at least 70% who had no recent related symptoms and were receiving intensive medical treatment, does adding a procedure provide meaningful extra protection?

The researchers conducted two separate trials: one testing carotid stenting and the other testing carotid endarterectomy, each against intensive medical treatment alone.

In the stenting trial, the main study outcome occurred in about 6 out of every 100 people receiving intensive medical treatment alone, compared with about 3 out of every 100 people who also received a stent over four years.

The measured rates were 6.0% and 2.8%, an absolute difference of 3.2 percentage points.

Importantly, these numbers represent a combined study outcome: any stroke or death during the first 44 days, followed by stroke caused by reduced blood flow or a blockage on the side of the narrowed artery during the remaining follow-up. They are not simply the risk of having any stroke over four years.

In the separate surgery trial, the rates were 5.3% with medical treatment alone and 3.7% with surgery plus medical treatment. That difference was smaller and was not statistically significant — meaning the study could not establish a clear additional benefit from surgery in that comparison.

This doesn’t mean surgery never works. And because the procedures were tested in separate trials, CREST-2 does not prove that stenting is better than surgery.

What it does show is that modern medical treatment can achieve relatively low event rates, making the decision to add a procedure more selective than many people might expect.

Vascular Surgeon’s Take

The most common reaction to a scary-looking percentage is to want it fixed immediately. I understand that instinct, but it’s rarely the right first question.

The first question is whether you’ve had symptoms. The second is what your plaque and your overall health actually look like, beyond the percentage. Only after that does it make sense to ask whether a procedure adds real protection on top of what good medical treatment already gives you.

For people with recent symptoms, acting quickly matters.

For people without symptoms, the decision deserves careful consideration. Modern medical treatment is essential, and a procedure should be recommended when its expected benefits outweigh its risks.

The goal isn’t simply to make the narrowing disappear. It’s to prevent a stroke using the safest and most effective approach for your individual situation.

Related Reading

How Carotid Plaque Is Actually Evaluated and Treated

70% Carotid Stenosis: Do You Really Need Surgery?