High Tech Treatment: A Device that can Stop Strokes as they are Happening
In September, the Food and
Drug Administration approved the first device that can remove blood clots from
the brains of people who are having ischemic strokes. Stroke is the third
leading cause of death in this country, and 80 percent of strokes are the
ischemic kind. During an ischemic stroke, a blood clot lodges in a blood vessel
in the brain, stopping the flow of blood. Serious strokes can cause permanent
disability, including inability to move or speak, and even death. The faster
surgeons are able to restore blood flow, the less brain tissue suffers damage
and the less likely patients are to sustain permanent disability.
The current treatment for
a person who is having a stroke is a so-called “clot-busting” drug called tPA.
It dissolves the clot that’s causing the stroke. But tPA is effective only
during the first 3 hours of a stroke. Many patients miss that crucial window of
time, usually because they’re not able to get to the hospital fast enough. Other
patients may not be able to take tPA safely because they’re already taking
medications that affect blood clotting.
timeframe for treatment
The new device, which can
remove the stroke-causing blood clot, is called the MERCI Retriever. MERCI
stands for Mechanical Embolus Removal in Cerebral Ischemia. It can be used up
to 8 hours after a stroke begins. This extended timeframe for stroke treatment
brings hope of recovery to many more people. But it’s not foolproof. In clinical
trials, the device worked 40 percent of the time.
The Merci Retriever is
made of titanium and nickel and is shaped like a corkscrew. Patients who are
treated with the device have a catheter inserted into their groin and up to the
blocked artery in the brain, where dye is injected. The dye provides an outline
of the blood vessel and shows where the clot is. Surgeons thread the Merci
Retriever through the artery to suction out the clot and restore blood flow.
The procedure generally
takes 2 to 3 hours. Recovery can be instantaneous. While patients are still
lying on the table, they can often recover their ability to move or speak.
The Food and Drug Administration