'Vacuum' Device Is a Clot Buster
New Treatment Could Help Stroke Patients When Standard Treatment Fails
Feb. 22, 2008 (New Orleans) -- A tiny vacuum-cleaner-like device can
help stroke patients when standard clot-busting drugs fail, researchers
Called Penumbra, the recently approved device suctions out clots that can
cause an ischemic stroke.
The most common type of stroke, ischemic stroke occurs when blood flow to an
area of the brain is compromised by a blood clot. This leads to the death of
brain cells and brain damage.
Penumbra restored blood flow in 82% of 125 patients studied, says Cameron
McDougall, MD, chief of endovascular neurosurgery at the Barrow Neurological
Institute in Phoenix.
"There were no serious adverse events associated with the procedure, and
nearly 60% of patients were better neurologically by the time they left the
hospital," he tells WebMD.
Also, one in four patients had no to minimal disability three months
The findings were presented at the American Stroke Association's (ASA)
International Stroke Conference.
Penumbra Helps When tPA Fails
About 780,000 Americans suffer a stroke each year and more than 150,000 of
them die. Survivors often face serious disability.
For patients who suffer an ischemic stroke, tissue plasminogen activator, or
tPA, can mean the difference between permanent brain damage and a return to
normal activities. TPA breaks up the clot, restoring blood flow to the
But tPA has to be administered in the first three hours after symptoms
strike, and the vast majority of people fail to get to the hospital in time.
Plus, it only works in about 40% of patients who get it.
Penumbra could help both these groups of people, McDougall says.
A catheter is inserted through a small puncture in the groin. Under X-ray
guidance, it is advanced through the blood vessels until it reaches the closest
edge of the blockage. A wire is advanced to dislodge the clot, which is sucked
into the catheter.
McDougall says that originally, the system had a plan B -- a clot-grabbing
device that doctors could use if the vacuum failed. "But we never really
needed it," he says.
Not everyone benefited from the new device. By three months after the
procedure, about one in three of the patients had died, many due to bleeding in
Given the severity of their illness, "this was not an unexpected
result," says Philip Gorelick, MD, head of the committee that chose which
studies would be presented at the meeting and chairman of neurology at the
University of Illinois in Chicago.
They "had ischemic stroke that was pretty severe for a clinical
trial," he tells WebMD.
Penumbra isn't the only clot-dislodging device. Doctors can also use a
corkscrew-shaped wire called the Merci Retriever to pull out clots.
According to McDougall, the two devices compare "favorably." But the
only way to really know is to pit one against the other in a clinical trial,
The new study was sponsored by Penumbra Inc.