James drove himself to the urgent care clinic.

He was 61 years old, a retired postal worker from outside Buffalo, and that morning he had experienced something strange: while eating breakfast, his right hand suddenly stopped working. Not painfully — it just went weak, clumsy, like it was someone else's hand. He set down his fork. His wife said something to him and he tried to respond, but the words came out wrong. Tangled. Not what he meant.

And then, about eight minutes later, it was gone. His hand worked. His speech came back. He ate the rest of his eggs.

His wife wanted to call 911. He said no — it passed, he was fine, it was probably nothing. He'd go to urgent care just to be safe.

The urgent care physician sent him directly to our emergency department. He arrived four hours after his symptoms had resolved, frustrated that everyone was making a fuss over something that had already gone away.

We found a near-total blockage of his left carotid artery. He was admitted, started on dual antiplatelet therapy, and had a carotid endarterectomy two days later. His surgeon told him afterward that if he had gone home and waited — if he had scheduled a regular neurology appointment and come in next week — there was a meaningful chance he would have had a devastating stroke before he got there.

James had experienced a TIA. And his instinct — it's gone now, so I'm fine — is the instinct that kills people.

What a TIA actually is

A transient ischemic attack — TIA — is a stroke that resolves on its own. A clot temporarily blocks blood flow to part of the brain, symptoms appear, and then the clot either breaks up or shifts before permanent cell death occurs. The symptoms vanish, usually within minutes, almost always within 24 hours.

For decades, TIAs were called "mini-strokes" — a term I dislike because it implies something smaller and safer than a stroke. The mechanism is identical. The cause is identical. The only difference is whether the blockage lasts long enough to cause permanent damage. And that distinction depends on factors — the size of the clot, the location of the artery, the state of the collateral circulation — that no one can see from the outside.

The more accurate frame: a TIA is a stroke that happened to resolve. It is not a near-miss. It is evidence that your brain's blood supply is vulnerable right now, and that the next event may not resolve.

"Mini-stroke" is a dangerous name. It makes people think they dodged something small. What they actually did was survive a warning. The question is whether they'll act on it.

What TIA symptoms look like

TIA symptoms are identical to stroke symptoms — because they are stroke symptoms. The only difference is duration. They include:

  • →Sudden weakness or numbness on one side of the body — face, arm, or leg
  • →Sudden difficulty speaking or understanding speech
  • →Sudden vision loss or double vision in one or both eyes
  • →Sudden severe dizziness, loss of balance, or coordination problems
  • →Sudden confusion or difficulty understanding what's happening

The critical word in every one of those bullet points is sudden. Stroke and TIA symptoms don't build up gradually over hours the way a migraine might. They arrive in seconds — like a light switching off.

One symptom that deserves special attention: amaurosis fugax — a temporary, painless loss of vision in one eye that patients often describe as a curtain or shade coming down across their visual field. It lasts seconds to minutes, then clears completely. It is caused by a tiny embolus briefly blocking the ophthalmic artery — a branch of the carotid. It is, in every clinical sense, a TIA of the eye. And it is almost always dismissed as "my vision did something weird."

If you or someone you know has experienced anything that sounds like the above — even if it lasted only two minutes and felt like nothing — please read the next section carefully.

The 48-hour window that changes everything

Here is the number that should motivate every person who has ever had a TIA — or watched someone have one — to act immediately:

In the days following a TIA, the risk of a full stroke is highest in the first 48 hours. Studies consistently show that 10–15% of TIA patients will have a stroke within 3 months if untreated — and the majority of those strokes happen within the first two days.1

That's not a slow-moving risk. That's an emergency playing out in slow motion.

The reason this window matters is that TIA is often caused by something that can be treated — a carotid artery with significant narrowing, a clot source in the heart, a small vessel with unstable plaque. If we find that cause and treat it urgently, we can interrupt the chain of events before the next, potentially permanent, stroke occurs.

The EXPRESS study, published in The Lancet, demonstrated this directly: when TIA patients were treated urgently — same-day imaging, same-day medications — the risk of subsequent stroke was reduced by 80% compared to delayed treatment.2 Eighty percent. Achieved not with some novel surgical technique or experimental drug, but with rapid evaluation and basic treatment that has existed for decades.

The intervention is time. The barrier is the patient deciding that because the symptoms are gone, so is the danger.

Clinical note

In the emergency department, we use the ABCD² score to estimate short-term stroke risk after TIA — factoring in Age, Blood pressure, Clinical features, Duration of symptoms, and whether the patient has Diabetes. High-risk patients (score ≥ 4) are typically admitted for monitoring. But regardless of score, the workup — brain imaging, vascular imaging, cardiac monitoring, labs — should happen urgently. Risk stratification guides intensity of monitoring; it doesn't change the urgency of evaluation.

What we actually do when you come in

When a patient arrives in the emergency department with a suspected TIA — even one where symptoms have fully resolved — here is what happens:

Brain imaging. A CT scan rules out hemorrhage. An MRI with diffusion-weighted imaging (DWI) looks for early evidence of ischemia — small bright spots that indicate cells have already been injured, even if symptoms have resolved. About 30–50% of "TIAs" actually show evidence of infarction on MRI.3 This matters because it changes the diagnosis from TIA to stroke — and with it, the treatment plan.

Vascular imaging. A CT angiogram or MR angiogram of the head and neck looks for arterial stenosis — narrowing of the carotid arteries or intracranial vessels that might explain what happened. This is what found James's blockage.

Cardiac monitoring. Atrial fibrillation — an irregular heart rhythm — is one of the most common causes of embolic stroke and TIA. It can be intermittent and invisible on a standard ECG. We monitor heart rhythm for at least 24 hours; in some patients, a longer-term implantable monitor is placed to catch paroxysmal AF that only appears occasionally.

Blood work. Complete blood count, coagulation studies, lipids, glucose, hemoglobin A1c. We're looking for contributing factors — a clotting disorder, severely elevated lipids, poorly controlled diabetes — that inform how aggressively we treat.

Antiplatelet therapy. Unless a cardioembolic cause (like AF) is identified, most TIA patients are started on antiplatelet medication — aspirin plus clopidogrel for the first 21 days, based on the POINT and CHANCE trials, then aspirin alone long-term.4

None of this is exotic. All of it is available at any stroke-capable hospital. But it only helps if you show up.

The conversation I have every week

Someone sits in front of me — or their family member does — and tells me about an episode that happened two days ago, or last week, or three months ago. The arm that went weak. The speech that came out wrong. The curtain across the eye that lasted about a minute and then lifted.

"It went away," they say. "I figured it was nothing."

Sometimes it is, in fact, nothing — a migraine with aura, a peripheral nerve issue, low blood sugar. My job is to figure out which.

But a meaningful portion of the time, it isn't nothing. It's a carotid artery that's 80% blocked. It's intermittent atrial fibrillation throwing tiny clots. It's a patent foramen ovale passing clots through a hole in the heart that was supposed to close at birth. All of them treatable. All of them dangerous. All of them sitting there silently, waiting for the next event.

The difference between the patients who do well and those who don't is almost never which hospital they went to or which neurologist they saw. The difference is usually whether they came in at all — and when.

If you had a TIA last week and haven't been evaluated yet, please stop reading this and call your doctor or go to an emergency department. The rest of this article will still be here. The window may not be.

TIA vs. stroke: the question patients always ask

The most common question I get: "How do I know if what I had was a TIA or a stroke?"

Honestly? You usually can't tell from the outside. And we often can't tell without imaging either. The traditional definition of TIA was symptoms lasting less than 24 hours with no evidence of infarction — but that definition has evolved. We now know that many "TIAs" leave permanent changes on MRI. Which is why we have largely moved away from the clinical time-based definition and toward a tissue-based one: if there's evidence of infarction, it's a stroke, regardless of whether symptoms resolved.

From a practical standpoint, this distinction changes the clinical management somewhat — but not the urgency of evaluation. Whether you had a TIA or a small stroke that fully resolved, the workup, the monitoring, and the treatment approach are essentially the same. You need to be seen urgently either way.

What happened to James

James had his carotid endarterectomy on day two of his admission — a surgical procedure to clean out the buildup of plaque in his left carotid artery. He went home on aspirin and a statin. His blood pressure, which he'd been "managing" by mostly ignoring his medication, was brought under control before discharge.

He came back to see me in clinic six weeks later. He told me he almost hadn't gone to urgent care. He told me his wife had been trying to call 911 when he stopped her. He told me that if he'd known what a TIA was — that it wasn't just a weird episode that passed, but a specific and urgent warning — he would have let her make that call.

"Nobody ever explained it to me that way," he said.

That's why I wrote this.

A TIA is not a near-miss. It is a warning issued by a brain under threat, in the only language it has — symptoms. When those symptoms resolve, the temptation is to believe the threat has passed. It hasn't. The cause is still there. The clock is still running. And the most powerful thing modern medicine can offer — urgent evaluation and treatment — only works if you walk through the door.

Call 911. Go to the emergency department. Tell them when the symptoms started, even if they're gone now. Let us do the rest.