New device to remove stroke-causing blood clots proves better than standard tool

August 26, 2012
The Solitaire FR Revascularization Device is a new device that restores blood flow and retrieves clots from blocked blood vessels in patients experiencing acute ischemic stroke. Credit: Covidien

Stroke is the fourth leading cause of death and a common cause of long-term disability in the United States, but doctors have very few proven treatment methods. Now a new device that mechanically removes stroke-causing clots from the brain is being hailed as a game-changer.

In a recent clinical trial, the SOLITAIRE Flow Restoration Device dramatically outperformed the standard mechanical treatment. Findings from the trial, called SOLITAIRE With the Intention for Thrombectomy (SWIFT), are published online today in the journal The Lancet and will also appear in a later print edition of the journal.

SOLITAIRE, which was approved by the U.S. Food and Drug Administration in March, is among an entirely new generation of devices designed to remove blood clots from blocked brain arteries in patients experiencing an ischemic stroke. It has a self-expanding, stent-like design, and once inserted into a blocked artery using a thin catheter tube, it compresses and traps the clot. The clot is then removed by withdrawing the device, reopening the blocked blood vessel.

"This new device is significantly changing the way we can treat ischemic stroke," said the study's lead author, Dr. Jeffrey L. Saver, director of the UCLA Stroke Center and a professor of neurology at the David Geffen School of Medicine at UCLA. "We are going from our first generation of clot-removing procedures, which were only moderately good in reopening target arteries, to now having a highly effective tool."

Results of the study showed that the device opened blocked vessels without causing symptomatic bleeding in or around the brain in 61 percent of patients. The standard FDA–approved mechanical device—a corkscrew-type clot remover called the MERCI Retriever—was effective in 24 percent of cases. The use of SOLITAIRE also led to better survival three months after a stroke. There was a 17.2 percent mortality rate with the new device, compared with a 38.2 percent rate with the older one.

About 87 percent of all strokes are caused by blood clots blocking a blood vessel supplying the brain. The stroke treatment that has received the most study is an FDA–approved clot-busting drug known as tissue plasminogen activator, but this drug must be given within four-and-a-half hours of the onset of stroke symptoms, and even more quickly in older patients.

When clot-busting drugs cannot be used or are ineffective, the clot can sometimes be mechanically removed during, or beyond, the four-and-a-half–hour window. The current study, however, did not compare mechanical clot removal to drug treatment.

For the trial, researchers randomly assigned 113 stroke patients at 18 hospitals to receive either SOLITAIRE or MERCI therapy within eight hours of stroke onset, between January 2010 and February 2011. The patients' average age was 67, and 68 percent were male. The time from the beginning of stroke symptoms to the start of the clot-retriever treatment averaged 5.1 hours. Forty percent of the patients had not improved with standard clot-busting medication prior to the study, while the remainder had not received it.

At the suggestion of a safety monitoring committee, the trial was ended nearly a year earlier than planned due to significantly better outcomes with the experimental device.

Other statistically significant findings included:

  • 2 percent of SOLITAIRE-treated patients had symptoms of bleeding in the brain, compared with 11 percent of MERCI patients.
  • At the 90-day follow-up, overall adverse event rates, including bleeding in the brain, were similar for the two devices.
  • 58 percent of SOLITAIRE-treated patients had good mental/motor functioning at 90 days, compared with 33 percent of MERCI patients.
  • The SOLITARE device also opened more vessels when used as the first treatment approach, necessitating fewer subsequent attempts with other devices or drugs.
"Nearly a decade ago, our UCLA Stroke Center team invented the first stroke retrieval device—the MERCI Retriever—and now we are pleased to have helped develop and successfully test a superior, next-generation clot removing device," said Dr. Reza Jahan, associate professor of radiology at UCLA and the study's principal neurointerventional investigator, who also led the pre-clinical studies. "It is exciting to have a highly effective new tool that can improve the outcomes for more stroke patients."

Explore further: New device performs better than old for removing blood clots

Related Stories

New device performs better than old for removing blood clots

February 3, 2012
An experimental blood clot-removing device outperformed the FDA-approved MERCI; retriever device, according to late-breaking science presented at the American Stroke Association's 2012 International Stroke Conference.

The Medical Minute: Solitaire for stroke -- It's not a game

May 22, 2012
Stroke is the fourth leading cause of death in North America -- down from third. Despite this "improvement," stroke remains the leading cause of adult disability. Ischemic strokes, caused by blood vessel blockages, are by ...

Clot-busting drug safe for stroke patients taking blood thinner

May 10, 2012
Acute ischemic stroke patients taking the blood thinner warfarin can be treated safely with the clot-busting drug tissue plasminogen activator (tPA), according to research presented at the American Heart Association's Quality ...

Cholesterol drugs may improve blood flow after stroke

April 26, 2011
(Medical Xpress) -- Cholesterol-lowering drugs known as statins may help clot-busting drugs treat strokes, according to researchers at Washington University School of Medicine in St. Louis.

Recommended for you

Researchers investigate the potential of spider silk protein for engineering artificial heart

August 18, 2017
Ever more people are suffering from cardiac insufficiency, despite significant advances in preventing and minimising damage to the heart. The main cause of reduced cardiac functionality lies in the irreversible loss of cardiac ...

Lasers used to detect risk of heart attack and stroke

August 18, 2017
Patients at risk of heart attacks and strokes may be spotted earlier thanks to a diagnosis tool that uses near-infrared light to identify high-risk arterial plaques, according to research carried out at WMG, University of ...

How Gata4 helps mend a broken heart

August 15, 2017
During a heart attack, blood stops flowing into the heart; starved for oxygen, part of the heart muscle dies. The heart muscle does not regenerate; instead it replaces dead tissue with scars made of cells called fibroblasts ...

Injectable tissue patch could help repair damaged organs

August 14, 2017
A team of U of T Engineering researchers is mending broken hearts with an expanding tissue bandage a little smaller than a postage stamp.

'Fat but fit' are at increased risk of heart disease

August 14, 2017
Carrying extra weight could raise your risk of heart attack by more than a quarter, even if you are otherwise healthy.

Air pollution linked to cardiovascular disease; air purifiers may lessen impact

August 14, 2017
Exposure to high levels of air pollution increased stress hormone levels and negative metabolic changes in otherwise healthy, young adults in a recent study conducted in China. Air purifiers appeared to lessen the negative ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.