Transient ischemic attacks (TIAs) are often called mini-strokes, but don’t let the name fool you—they’re a big deal. Nearly 800,000 Americans have an ischemic stroke each year, but about 240,000 of those are actually TIAs.
About 87 percent of strokes are ischemic strokes, where blood flow to the brain is partially or fully blocked. For up to 24 hours, a TIA is indistinguishable from an ischemic stroke, says says Laszlo Miskolczi, MD, a neurointerventional radiologist at Holy Cross Hospital in Fort Lauderdale, Florida. What changes in those 24 hours, and what makes a TIA different from a stroke? Read on to find out.
TIA vs. stroke
Within the first 24 hours, ischemic strokes and TIAs are virtually indistinguishable. “The basic definition of a transient ischemic attack is something that looks like a stroke, but spontaneously goes away after 24 hours,” says Miskolczi. “We don’t know if it’s a TIA or a stroke when it starts. We’ll know after 24 hours.”
Both ischemic strokes and TIAs are the result of a blockage in an artery or arteries that restrict blood flow to the brain. But with a TIA, “the body’s thrombolytic system—the mechanism of dissolving blood clots—takes care of it,” Miskolczi says. “Then the artery reopens and symptoms go away.”
Problem solved, right? Wrong, says Miskolczi. “Patients tend to blow these off,” he says. “But there is always a reason a blood clot formed. You can have luck one or two or three times, but if you don’t take care of yourself, luck runs out.”
A TIA is often called a “warning stroke” because your body is warning you that you’re at serious risk for a stroke or a heart attack. The clot that caused the TIA may have dissolved on its own, but if your arteries are full of plaque, it’s only a matter of time before more breaks off from the artery wall, blood cells form around it to form a clot and the clot causes a stroke or a heart attack.
Good news about TIA
Having a TIA puts you at risk for a full-on stroke or another cardiovascular event, but a 2016 study published in the New England Journal of Medicine found that the risk was lower than previous research suggested. The study, of more than 4,700 people, found that the chance of having a stroke 90 days after a TIA was 3.7 percent, as opposed to the 12 to 20 percent previous studies found. The authors suggested this was because treatment after a TIA—anticoagulants to stop blood clots, and medicines to manage high blood pressure and high cholesterol—has improved.
Miskolczi says that the risk for more serious problems after a TIA depends on the underlying disease and its treatment. If the TIA was caused by heart disease, but the patient is on blood thinners, the risk of a stroke or heart attack is small. “But if we don’t treat a severe problem, it will cause irreversible damage.”
TIA symptoms
The symptoms of a TIA are the same as the symptoms of a stroke. When you suspect someone is having a stroke, you have to B.E. F.A.S.T. in recognizing it.
- Balance—is there a sudden loss of balance or coordination?
- Eyes—is there sudden vision loss, distorted vision or blind spots in one eye?
- Face—ask the person to smile and see if one side of the mouth droops.
- Arms—ask the person to raise both arms over their head; does one arm drift down?
- Speech—does the speech sound slurred?
- Time—if you notice any of these symptoms, call 911 right away.
TIA diagnosis
If you think you or someone else is having a stroke or a TIA, call 911 immediately. Do not take yourself to the hospital or ask someone to take you. You’ll get to the hospital sooner if you call an ambulance; stroke treatment is more effective the sooner it’s given. “Every minute counts,” says Miskolczi. “Every minute, 2 million brain cells can die during a stroke.”
Doctors work on the presumption that anyone with the symptoms described above is having a stroke. Brain scans can help doctors see what areas of the brain have been affected, while blood vessel scans and heart tests can show them where the clot is and help them determine what has caused it.
Treatment and prevention
A TIA by definition will go away on its own, but you’re not out of the woods yet. Treating a TIA depends in part on managing the condition that caused it, such as atherosclerosis, high cholesterol or high blood pressure. Doctors will often send patients home with an antiplatelet or anticoagulant medication.
Prevention of another TIA, a stroke or a heart attack is largely a matter of lifestyle choices. Lifestyle changes and especially physical activity is critical in recovering from a TIA. A small December 2016 study published in Neurology suggests that being physically inactive puts you at a fivefold greater risk of a stroke, heart attack or vascular death for up to three years after your TIA. Controlling your blood pressure and cholesterol can also help you avoid more serious complications.
“We usually tell people to lower fat and cholesterol consumption, stop smoking, exercise, lose weight. Basic things,” says Miskolczi. “But if a patient can take care of all of these and they take their medication, they can lower their risk of having a stroke by 50 to 80 percent.”
