Featured Research

from universities, journals, and other organizations

New design for mechanical heart valves

Date:
November 23, 2011
Source:
American Physical Society
Summary:
The heart's valves are asymmetrical. Mechanical heart valves, are symmetrical. Could an asymmetric design improve blood flow?

The heart's valves, which guarantee the unidirectional flow of blood from one chamber to another, are asymmetrical. For example, the two flaps of the heart's mitral valve -- which regulates blood flow between the left atrium and the left ventricle -- vary in size by up to 70 percent.

This arrangement, says fluid mechanicist Marija Vukicevic from the University of Trieste (now a researcher at Clemson University), naturally drives blood flow along the lateral wall of the ventricle; from there, blood takes a smooth turn creating a large vortex that redirects the blood toward the aorta (the main blood vessel of the heart), through which it exits out into the body.

Mechanical heart valves, however, are symmetric in design -- with both flaps of a mitral valve replacement of identical size -- and that, Vukicevic and colleagues have found, disrupts the flow of blood.

"Blood flow in the left ventricle is characterized by a physiological vortex that disappears when a symmetric mechanical prosthesis is implanted," she says. With such prostheses, which are implanted into an estimated 60,000 patients each year in the United States, blood flows across the ventricular chamber then hits the opposite side instead of taking a turn, leading to a higher effort in the heart muscle and a disruption in its regulatory mechanism.

To see if a more naturally asymmetric design could improve blood flow, Vukicevic, along with Gianni Pedrizzetti of the University of Trieste and colleagues created aluminum models of asymmetric valves, similar in size to the valves of an adult human heart. The valves were tested in a mock ventricle, made of silicon, through which the researchers could visualize fluid flow. The pattern and rate of flow through the valves, the researchers found, closely matched that of a healthy heart. "We recommend that industries test asymmetric prototypes for mitral valve replacement," she says.

Vukicevic is discussing the findings in a talk at the APS Division of Fluid Dynamics Meeting, which takes place Nov. 20-22, 2011, at the Baltimore Convention Center in the historic waterfront district of Baltimore, Maryland.


Story Source:

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


Cite This Page:

American Physical Society. "New design for mechanical heart valves." ScienceDaily. ScienceDaily, 23 November 2011. <www.sciencedaily.com/releases/2011/11/111122113212.htm>.
American Physical Society. (2011, November 23). New design for mechanical heart valves. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2011/11/111122113212.htm
American Physical Society. "New design for mechanical heart valves." ScienceDaily. www.sciencedaily.com/releases/2011/11/111122113212.htm (accessed September 17, 2014).

Share This



More Health & Medicine News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Obesity Rates Steady Even As Americans' Waistlines Expand

Obesity Rates Steady Even As Americans' Waistlines Expand

Newsy (Sep. 17, 2014) Researchers are puzzled as to why obesity rates remain relatively stable as average waistlines continue to expand. Video provided by Newsy
Powered by NewsLook.com
President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com
Obama Orders Military Response to Ebola

Obama Orders Military Response to Ebola

AP (Sep. 16, 2014) Calling the Ebola outbreak in West Africa a potential threat to global security, President Barack Obama is ordering 3,000 U.S. military personnel to the stricken region amid worries that the outbreak is spiraling out of control. (Sept. 16) Video provided by AP
Powered by NewsLook.com
UN: 20,000 Could Be Infected With Ebola by Year End

UN: 20,000 Could Be Infected With Ebola by Year End

AFP (Sep. 16, 2014) Nearly $1.0 billion dollars is needed to fight the Ebola outbreak raging in west Africa, the United Nations say, warning that 20,000 could be infected by year end. Duration: 00:40 Video provided by AFP
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:
from the past week

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