Featured Research

from universities, journals, and other organizations

Tiny Device Blocks "Useless" Part Of Heart, Prevents Blood Clots

Date:
April 9, 2002
Source:
American Heart Association
Summary:
A tiny device implanted into the heart to prevent blood clots could reduce the risk of strokes in people with atrial fibrillation (AF), researchers report in Circulation: Journal of the American Heart Association.

DALLAS, April 9 – A tiny device implanted into the heart to prevent blood clots could reduce the risk of strokes in people with atrial fibrillation (AF), researchers report in today’s rapid access publication of Circulation: Journal of the American Heart Association.

Related Articles


About 2 million Americans have been diagnosed with atrial fibrillation, a type of irregular heartbeat. About 15 percent of strokes occur in people with atrial fibrillation. Each year, about 600,000 Americans suffer a new or recurrent stroke.

Previous studies indicate that more than 90 percent of nonrheumatic AF-related strokes result from a blood clot that forms in the left atrial appendage, a small, thumb-shaped pouch in the heart’s left upper chamber. Such clots can block a blood vessel leading to the brain, causing a stroke.

In a multicenter trial, German researchers successfully sealed off the left atrial appendage of 15 chronic AF patients with a novel procedure called PLAATO.

PLAATO, which stands for percutaneous left atrial appendage transcatheter occlusion, uses a catheter to place a blocking device at the mouth of the appendage.

“The left atrial appendage has no purpose; no one needs it,” says study author Horst Sievert, M.D. “Its only function is to form clots. It can be blocked with no disadvantage to the patient.”

The blocking device is a self-expanding metal cage made of nitinol that pops open as the metal warms up inside the body. The cage is covered with a membrane, which both blocks the atrial appendage and allows normal tissue to grow into the device.

“This study was to show that PLAATO was technically feasible,” says Sievert, a senior consultant at the Cardiovascular Center of Bethanien Hospital in Frankfurt, Germany. “Not only was it possible, but after six months we have had no strokes and no late complications.”

Stroke is the most serious consequence of AF.

The anti-clotting drug warfarin can prevent strokes in AF patients. However, “this drug’s disadvantages are that it can cause bleeding, it is difficult to control, and many patients cannot take it, which puts them at high risk of stroke.” Sievert says.

Therefore, another treatment is needed to prevent strokes in people with AF.

Researchers selected 15 patients whose AF was not caused by rheumatic fever. All of the patients were at high risk of stroke because they could not take warfarin for long periods. Participants ranged in age from 59 to 78.

Using an ultrasound technique called transesophageal echocardiography to guide them, the researchers threaded a catheter containing the PLAATO device to the entrance of the atrial appendage.

If the initial placement was not adequate, the researchers collapsed the device and repositioned it. Once inserted properly into the mouth of the atrial appendage, the nitinol cage expanded to its proper shape.

Tiny spikes attached to the alloy cage that protrude through its covering anchored the device in place.

The left atrial appendage was successfully blocked in all 15 patients, Sievert says.

Each patient received a device that was 20 percent to 40 percent larger than the opening of his or her left atrial appendage. During the procedure, four patients had the device removed and replaced with one of a different size with no problems. One patient had a complication during the procedure, so four weeks later the procedure was repeated, this time successfully.

The patients’ implants, when fixed in place, ranged in diameter from 18 to 32 millimeters. The average time for the procedure was 92.7 minutes.

As promising as the new findings appear, Sievert emphasizes that additional studies are needed to confirm the successful implantation of the PLAATO device and to show that the therapy will prevent strokes.

“This initial study supports the concept that implanting a mechanical device to block the left atrial appendage can be done safely and with relative ease,” Sievert says. “It may became a valuable alternative for patients with chronic, non-rheumatic AF in whom standard anticoagulation therapy is contraindicated or poorly tolerated.”

Co-authors are Michael D. Lesh, M.D.; Thomas Trepels; Heyder Omran, M.D.; Antonio Bartorelli, M.D.; Paola Della Bella, M.D.; Toshiko Nakai, M.D.; Mark Reisman, M.D.; Dirk Fleschenberg; Ulrike Krumsdorf; and Detlef Scherer, M.D.


Story Source:

The above story is based on materials provided by American Heart Association. Note: Materials may be edited for content and length.


Cite This Page:

American Heart Association. "Tiny Device Blocks "Useless" Part Of Heart, Prevents Blood Clots." ScienceDaily. ScienceDaily, 9 April 2002. <www.sciencedaily.com/releases/2002/04/020409073831.htm>.
American Heart Association. (2002, April 9). Tiny Device Blocks "Useless" Part Of Heart, Prevents Blood Clots. ScienceDaily. Retrieved March 3, 2015 from www.sciencedaily.com/releases/2002/04/020409073831.htm
American Heart Association. "Tiny Device Blocks "Useless" Part Of Heart, Prevents Blood Clots." ScienceDaily. www.sciencedaily.com/releases/2002/04/020409073831.htm (accessed March 3, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Tuesday, March 3, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Treadmill Test Can Predict Chance Of Death Within A Decade

Treadmill Test Can Predict Chance Of Death Within A Decade

Newsy (Mar. 2, 2015) Johns Hopkins researchers analyzed 58,000 heart stress tests to come up with a formula that predicts a person&apos;s chances of dying in the next decade. Video provided by Newsy
Powered by NewsLook.com
Going Gluten-Free Could Get You A Tax Break

Going Gluten-Free Could Get You A Tax Break

Newsy (Mar. 2, 2015) If a doctor advises you to remove gluten from your diet, you could get a tax deduction on the amount you spend on gluten-free foods. Video provided by Newsy
Powered by NewsLook.com
GlaxoSmithKline and Novartis Try Swapping Success

GlaxoSmithKline and Novartis Try Swapping Success

Reuters - Business Video Online (Mar. 2, 2015) GlaxoSmithKline and Novartis have completed a series of asset swaps worth more than $20 billion. As Grace Pascoe reports they say the deal will reshape both drugmakers. Video provided by Reuters
Powered by NewsLook.com
How Can West Africa Rebuild After Ebola?

How Can West Africa Rebuild After Ebola?

Reuters - Business Video Online (Mar. 2, 2015) How best to rebuild the three West African countries struggling with Ebola will be discussed in Brussels this week. As Hayley Platt reports Sierra Leone has the toughest job ahead - its once thriving economy has been ravaged by the disease. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins