Due to their transient nature, symptoms of a mini-stroke are often brushed off as benign. But research shows up to 43 percent of stroke sufferers experience the fleeting condition prior to an attack. These patients typically report severe headaches, problems with vision, or difficulty comprehending others in the days leading up to a stroke. But seeking curative treatment when these signs appear, could significantly lower the odds of suffering a full-blown ischaemic stroke.
Stroke types are distinguished by their cause, and the majority of events occur when blood circulation ceases due to a clot.
Before bringing blood flow to a complete halt, however, a blockage can cause blood flow to falter in short episodes.
This is known as a transient ischaemic attack (TIA), which interrupts circulation to part of the brain briefly, before it is restored.
According to early research, symptoms of TIA may occur in up to 43 percent of patients up to a week prior to an ischemic stroke.
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In a 2005 study, scientists found that almost one in every three stroke survivors suffered a mini-stroke prior to the actual event.
The findings showed that in these sufferers, most mini-stroke symptoms occurred within the preceding seven days.
Symptoms of mini-stroke
Symptoms of TIA closely resemble those of an ischaemic stroke, but subtle differences exist.
Warning signs include numbness or weakness in the face, arms, or legs, sudden confusion, trouble speaking, and trouble comprehending others.
But some sufferers report issues with eyesight, or experience trouble understanding others.
The health organisation Stroke explains: “[TIA] is the same as a stroke, except that the symptoms only last for a short amount of time.
“This is because circulation only stops momentarily, before resuming.
“This can cause sudden symptoms similar to a stroke, such as speech and visual disturbances, and numbness or weakness in the face, arms and legs,” adds the NHS.
“But a TIA does not last as long as a stroke. The effects last a few minutes to a few hours and fully resolve within 24 hours.
“The reasons symptoms are able to resolve rapidly is thanks to the body’s ability to dissolve a clot.
But when clot remains in place, it can destroy brain cells by starving them of oxygen and other key nutrients.
Doctor Christopher Anderson, stroke services at Harvard-affiliated Massachusetts General Hospital, said: “A TIA can be a harbinger of a much more serious stroke.
“As many as 17 percent of people who have a TIA will suffer a full-blown ischaemic stroke within the next 90 days, with the greatest risk in the first week, according to Harvard Health.
An ischaemic attack, which accounts for 80 percent of events, occurs when a clot becomes lodged inside an artery, but some strokes are caused by a bleed in the brain.
A TIA, however, is always caused by momentary loss of blood flow.