'Mini' stroke can cause major disability, may warrant clot-busters

Patients with transient ischemic attack, TIA or "mini" stroke, are not typically given clot-busting drugs because the condition is considered too mild to treat. However, 15 percent of patients had some disability 90 days after a mini stroke. Some patients with minor stroke may benefit from clot-busting drug treatment.

"Our study shows that TIA and minor stroke patients are at significant risk of disability and need early assessment and treatment," said Shelagh Coutts, M.D., lead author of the study at Foothills Hospital in Calgary, Alberta, Canada. "We should be imaging patients earlier and be more aggressive in treating patients with thrombolysis if we can see a blockage no matter how minor the symptoms are."

Thrombolysis is a treatment used to dissolve dangerous clots and restore healthy blood flow to the brain. TIA and minor stroke patients don't typically receive this treatment because the condition is frequently not deemed serious enough to warrant it, researchers said.

Among the 499 patients studied, 15 percent had at least minor disability 90 days after their original "mini stroke." Minor disability was defined as being unable to carry out previous activities, but capable of and handling personal affairs without assistance.

Computed tomography (CT) scans showed some "mini stroke" patients had narrowed blood vessels in the brain, and others reported ongoing or worsening symptoms. Those patients were more than twice as likely to have disability at 90 days. Coutts suggests that thrombolysis treatment should be considered in these patients.

Patients with type 2 diabetes had a similarly high risk of disability. Also, women were nearly twice as likely as men to be disabled 90 days after TIA.

"For every second after a mini stroke, the patient's brain may be losing oxygen -- possibly leading to a major event," Coutts said. "If a scan finds that you have a narrowing of a blood vessel in or outside of the brain, you are at a high risk of being disabled."

Recurrent strokes posed the greatest threat to patients. Of those who had recurrent strokes, 53 percent were disabled, compared to 12 percent of patients without a recurrent stroke.

In 2009, the American Heart Association/American Stroke Association recommended immediate action and thorough testing for TIA -- much like the exams performed after a full-blown stroke. These exams can show blockage in a brain blood vessel, which can increase patients' risk of a subsequent, more serious event.

"The symptoms of a TIA -- abrupt onset of inability to move one side of your body, numbness on one side, dizziness and trouble walking -- may pass quickly," Coutts said. "But, if you experience them, you should immediately go to the hospital, where proper scans can be done. Based on these results we have started a trial in Canada giving clot busting drugs to patients with mild symptoms, but blocked blood vessels in the brain.

"If ignored, these symptoms can lead to death. This is not a benign disease."