Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cardiovascular disease: The mechanics of prosthetic heart valves

21.12.2012
Computer simulations of blood flow through mechanical heart valves could pave the way for more individualized prosthetics
Every year, over 300,000 heart valve replacement operations are performed worldwide. Diseased valves are often replaced with mechanical heart valves (MHVs), which cannot yet be designed to suit each patient’s specific needs. Complications such as blood clots can occur, which can require patients to take blood-thinning medication.

To investigate why such complications occur, Vinh-Tan Nguyen at A*STAR’s Institute of High Performance Computing, Singapore, together with scientists at the National University of Singapore and institutions across the USA, have developed a new computer model to simulate the dynamics of blood flow through MHVs1.

“The current practice for heart valve replacement in patients is a one-size-fits-all approach where a patient is implanted with the best-fit valve available on the market,” explains Nguyen. “The valves are well designed for general physiological conditions, but may not be suitable for each individual’s particular heart condition.”

The researchers focused on the blood flow dynamics in a prosthetic valve known as a bileaflet MHV. This type of MHV contains two mobile leaflets, or gates, which are held in place by hinges. The leaflets open and close in response to blood flow pressures through the valve. Little is known about the effect that the hinged leaflets have on blood dynamics, although such designs are suspected of causing blood clots.

The computer model developed by Nguyen and his team simulates pressure flows through bileaflet MHVs by representing blood vessels as a computational mesh, where calculations are performed for individual blocks of the mesh. Their crucial advance was in enabling this mesh to move and evolve in response to the leaflet movements.

The researchers validated their computer model through laboratory experiments with a full 3D reproduction of the heart's circulation system. Particle imaging equipment allowed them to visualize the fluid dynamics under different scenarios including pulsatile flow, which follows the pattern of a typical cardiac cycle.

“We obtained good agreement between our computer simulations and the experiments in terms of the magnitude and velocity of blood flow through the leaflets,” states Nguyen. The researchers also found that leaflet hinges might play a vital role in clotting, because individual hinges have different tolerances that can disrupt normal blood flow and cause stress in the vein walls.

This research is a first crucial step in understanding the impact of MHVs on blood flow. “Ultimately we hope to provide doctors with a tool to evaluate blood flow dynamics and other related aspects in patients with newly implanted valves,” says Nguyen.

The A*STAR-affiliated researchers contributing to this research are from the Institute of High Performance Computing

Journal information

Nguyen, V.-T., Kuan, Y. H., Chen, P.-Y., Ge, L., Sotiropoulos, F. et al. Experimentally validated hemodynamics simulations of mechanical heart valves in three dimensions. Cardiovascular Engineering and Technology 3, 88–100 (2012)

A*STAR Research | Research asia research news
Further information:
http://www.a-star.edu.sg
http://www.researchsea.com
http://www.researchsea.com/html/article.php/eml/1/aid/7539/cid/3

More articles from Medical Engineering:

nachricht VTT develops a simple but extremely sensitive magnetometer
25.11.2014 | VTT Technical Research Centre of Finland

nachricht New device may ease mammography discomfort
25.11.2014 | Radiological Society of North America

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Anzeige

Anzeige

Event News

Regional economic cooperation in Central Asia

21.11.2014 | Event News

Educating the Ecucators

13.11.2014 | Event News

36th Annual IATUL Conference 2015: Call for papers and posters

12.11.2014 | Event News

 
Latest News

Siemens expands software for mobile data management in the process industry

26.11.2014 | Trade Fair News

Microbial Communities for Health and Environment : Precise Measurements of Microbial Ecosystems

26.11.2014 | Life Sciences

VTT demonstrates new technique for generating electricity

26.11.2014 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>