August 23, 2013
News Review From Harvard Medical School -- Super-Early Drug Therapy Reduces Stroke Disability
A new study found that giving clot-busting drugs within 90 minutes of a mild to moderate stroke prevents or greatly reduces the chances of disability. Current guidelines recommend giving a clot-busting drug within 4.5 hours of symptoms. A large European study looked at the outcomes of 6,856 people diagnosed with ischemic stroke. Ischemic strokes are the most common type of stroke. They occur when a clot blocks blood flow to the brain. All of the patients received an intravenous (IV) clot-busting drug, called tissue plasminogen activator (tPA), within 4.5 hours. Doctors call this procedure thrombolysis. But patients who got the drug within 90 minutes of symptoms had little or no disability 3 months later, compared with patients who got thrombolysis after 90 minutes. The journal Stroke published the study online. HealthDay News wrote about it August 22.
By Howard LeWine, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
When a stroke strikes, brain cells die quickly. The faster you recognize a stroke and get to the hospital, the faster treatment can begin. And the greater your chance of near or complete recovery, especially if the stroke symptoms are mild to moderate.
It's a medical emergency similar to a heart attack. That's why many call it a "brain attack."
Brain cells require a constant supply of blood, which carries oxygen and nutrients. A stroke suddenly interrupts that supply. More than 80% of all strokes are caused by a blood clot blocking an artery supplying the brain. Doctors call this an ischemic stroke.
The clot may form in a blood vessel within the brain (thrombotic stroke). Or the clot may form elsewhere and travel to the brain (embolic stroke).
A large European study looked at the outcomes of 6,856 people diagnosed with ischemic stroke. All of them received an intravenous (IV) clot-busting drug called tissue plasminogen activator (tPA). Doctors call this procedure thrombolysis.
The drug was given to all patients within 4.5 hours from the time when stroke symptoms started. After 4.5 hours, tPA is less effective, and the risk of bleeding outweighs any small risk of benefit.
The researchers focused on:
Three months later, people who got thrombolysis after 90 minutes of symptoms appearing had less disability, compared with patients who got it later. This effect was only seen in people with mild to moderate stroke symptoms.
Patients with severe stroke symptoms were less likely to avoid disability in the future. This was true whether or not they received early thrombolysis. However, even patients with severe stroke symptoms should always be considered for thrombolysis. Results of the study were published online yesterday in the journal Stroke.
What Changes Can I Make Now?
If you suspect someone is having a stroke, think FAST:
Before injecting tPA, a doctor must be sure that the stroke is not caused by bleeding into the brain. This is called a hemorrhagic stroke. An MRI or CT scan must be done first. That's why it's so important for the 911 operator to know you suspect a stroke. The emergency department can then be ready to do the brain imaging quickly.
You can take steps to help prevent strokes:
What Can I Expect Looking to the Future?
We continue to see improved outcomes in people with acute stroke. But still too many people have disabling strokes that can be prevented with healthy lifestyle choices starting in childhood.