Time is Brain
Short but serious, mini-strokes deserve 9-1-1 attention
You’re watching TV in your favorite chair when, suddenly, you feel strange. Your right arm goes numb, and you drop the remote control. You try to call to your spouse, but you can’t find the words. After a few frightening minutes, the problems go away and you feel normal again. A visit to the emergency room confirms it: You’ve just had a transient ischemic attack (TIA), or mini-stroke.
Both strokes and TIAs are “brain attacks”—interruptions to the brain’s blood supply, usually due to a blood clot. But with a TIA, the interruption is too brief to cause brain damage. That doesn’t mean you should ignore it. In fact, symptoms of a TIA should prompt an immediate call to 9-1-1. A TIA means that a stroke may be on the way, perhaps within hours, if nothing is done to prevent it. Ten percent of patients who have had a TIA will have a stroke within three months—and, of those, half will experience that stroke within 48 hours. TIA patients also have twice the risk of heart attack as the general population.
“TIA is a medical emergency. Period,” says Elizabeth Noser, MD, clinical assistant professor in the Department of Neurology at The University of Texas Health Science Center at Houston (UTHealth) Medical School and holder of the James C. Grotta, MD Chair in Neurological Recovery and Stroke. "A TIA is a stroke that reverses itself. It’s the chance to try to understand what caused that event, then begin the right interventions so you won’t go on to develop stroke.” The majority of strokes are preventable. But prevention depends in large part on recognizing the symptoms of a brain attack and getting to the hospital fast.
Turning opportunity into action
The brain depends on free-flowing blood vessels to bring oxygen to its cells. Sometimes, a narrowed brain artery clots off; or a clot in a distant artery breaks off, travels to the brain, and becomes lodged in a small artery there. Either way, the abrupt blockage leads to oxygen deprivation that prevents brain cells from functioning. The victim develops sudden symptoms like weakness or numbness in the face, an arm or a leg; trouble speaking or understanding; trouble seeing out of one or both eyes; or trouble with balance or coordination. Some TIAs and strokes can cause sudden headache.
The body dissolves blood clots naturally, and most TIAs clear up in an hour or less. But, if a brain clot doesn’t dissolve quickly, it will kill brain cells—some 1.9 million of them per minute during a major stroke.
While doctors once thought mini-strokes left no brain damage, brain MRIs have revealed that up to one-third of TIA-like events actually do; those events are now defined as strokes. To be called a TIA, a brief brain attack has to leave no damage, and an MRI is the only way to tell the difference. If damage shows up in the brain scan, even in a person who feels normal again, then by definition it was a stroke.
Though a TIA can be frightening, it can also be a golden opportunity to prevent stroke. Beginning treatment within 24 hours can reduce the 90-day risk of stroke by as much as 80 percent. Unfortunately, many people don’t recognize the symptoms of a brain attack, don’t call 9-1-1, and miss their opportunity to avoid stroke. They may chalk up TIA symptoms to fatigue or old age, or think they must be all right because they aren’t in pain. While up to half a million Americans per year are diagnosed with TIA by a physician, another estimated half-million experience TIA symptoms without reporting them.
Marianne Greenfield, 72, chose to delay. She was dozing off at home when she awoke to find her right hand and right side of her face numb and tingly. Her husband urged her to get dressed and come to the hospital, but she decided to wait a few minutes to see if it went away. Fortunately, it did. She decided not to go to the hospital. But a few days later, she spoke to her doctor, and she learned how risky that decision had been. “I will not make that mistake again,” she says. Greenfield, who suffers from high blood pressure, high cholesterol, and atrial fibrillation, soon underwent a complete evaluation. Her symptoms turned out to be a TIA. Heeding her body’s warning, she began treatment, including aspirin, to reduce her risk of stroke.
Greenfield and her doctors are right to be cautious: Her age, medical conditions and history of a TIA put her at elevated risk for stroke. While high blood pressure, atrial fibrillation and diabetes are among the strongest stroke risk factors, being male and/or African American also raise the risk, as does having a family history of stroke or TIA. Other risk factors include smoking, drinking more than two alcoholic drinks per day and excess weight. Though people 55 or older are in the highest-risk age group for stroke and TIA, it can happen at any age. Actor Frankie Muniz, best known for his role in “Malcolm in the Middle,” was just 27 when he suffered a TIA last fall.
Treated like a stroke
What kind of tests do TIA patients get? The same ones that stroke patients do—that is, a rapid brain scan, blood tests and ultrasounds, for starters. TIA patients may also need to stay in the hospital. A patient whose TIA lasts longer than 10 minutes, for example, or whose ultrasound reveals clots that could break off at any moment, is likely to be admitted. Time is so crucial in potential stroke situations that at primary stroke centers like Memorial Hermann Hospital, a team of stroke experts is on call 24 hours a day. The team can evaluate stroke patients within minutes and offer fast treatment like clot-busting drugs or even clot removal. (For some patients with lower-risk symptoms, testing may be reasonably completed on an outpatient basis.)
Other tests include brain magnetic resonance imaging (MRI), which can detect subtle signs of brain damage; a magnetic resonance angiogram (MRA), which picks up on clogged brain vessels; and screening for high cholesterol and diabetes. Patients at research universities like UTHealth may be offered the chance to participate in a research study. Doctors also consider other potential explanations for the symptoms, such as seizure, brain bleed, tumors or migraine.
If a true TIA is suspected, a complete evaluation will be recommended even if the symptoms are gone. In fact, it’s uncommon for a TIA to last long enough for a health care provider to witness it. But the symptoms are still taken very seriously, and no one with TIA symptoms should feel sheepish about calling 9-1-1.
Remember the 3 R’s for stroke
How can stroke be prevented? People with risk factors may feel a sense of futility, as if there’s nothing they can do. But, while no one can change their age or family history, having a risk factor does not doom a person to having a stroke. Stroke prevention is well within reach of most patients, but it means understanding one’s own risk factors—and taking them seriously. Medical problems like heart disease can greatly improve with treatment and exercise. People who smoke have it in their power to quit. But it’s important to remain vigilant.
High blood pressure is a good example. Because high blood pressure weakens blood vessels, it raises stroke risk up to sixfold. The condition can be treated with medication. But simply visiting the doctor and receiving a prescription may not be enough. Taking the medication faithfully is crucial. Making sure it’s working is also extremely important: people respond differently to medications, and some require a combination to keep their blood pressure in a healthy range.
One way to be proactive is to keep a blood pressure journal. “I tell my patients, ‘Just like you know how much money you have in your wallet, you should know how your blood pressure is running,’” says Noser. “Blood pressure fluctuates all the time.” With information about day-to-day blood pressure changes, the doctor can tailor medications much more effectively. Self-care like this can go a long way toward ensuring that a stroke never arrives.
Above all, coping with the risk of stroke means knowing the 3 R’s: Reduce risk, Recognize symptoms, and Respond by calling 9-1-1. And that goes for TIAs, too. “You do not know if it’s a TIA or a stroke,” says Noser. “It’s a stroke until proven otherwise."