Artificial Heart Valves

By Daniel Wec

What are they?

• Artificial Heart Valves are devices that function as natural heart valves, pumping blood from one chamber of the heart to the next.

• They are implanted through open-heart surgery on individuals who have a defective heart valve or suffer from various heart valvular diseases.

• There are two types:- Mechanical- Biological or Tissue

History

• 1952 – Dr. Charles Hufnagel designed and implanted a mechanical heart into a thirty year old female.

• 1960 – The Starr-Edwards ball valve was created. It was based off of Dr. Charles Hufnagel’s design.

• 1969- The Bjork-Shiley valve started being used and it was based on a tilting disc design.

• 1979 – Bileaflet valves start being used and up to this day, their designs are still being improved upon.

Mechanical Heart Valves

• Allow blood to flow through their center but do have negative effects:

- Backflow.- Blood infection.- Patients must take blood thinning medication and get

blood tests done every 4-6 weeks.- Tend to get worn out.- Last around 25-35 years, since they are usually made

from titanium and/or carbon.

Biological Heart Valves• There are two types, tissue, and homograft.• Tissue:- Made from animal tissue, usually pig, but sometimes horses and cows.- Last for an average of 15 years.- Are similar to human tissue so they don’t require maintenance

through blood thinners and blood tests.- Higher chance of rejection.• Homograft Blood Valves- Actual human valves that are donated.- Less risk of infection.- No guarantee that the valve will be the correct size for a certain

patient.

Who Needs Mechanical Heart Valves?

• Mechanical Heart Valves are more likely implanted on patients who:

- Have a longer lifespan or are over 65.- Already have another mechanical heart valve

implanted.- Are already taking blood thinners or are healthy

enough to take them.- Have had kidney failure.

Who Needs Biological Heart Valves?

• Biological Heart Valves are most likely implanted on patients who:

- Are younger than 65.- Have had trouble with a prior mechanical

heart valve.- Cannot take blood thinners.- Are in the late stages of kidney failure.

Currently Being Used

The most common heart valves that are being used by cedars-sinai include the following:•Mechanical Heart Valves:-St. Jude Valve•Biological (Tissue) Heart Valves:-Carpentier-Edwards Pericardial Valve-St. Jude Toronto Stentless Porcine Valve

Future

• Improvements that researchers will attempt to make in the future include:

- Longer lifespan of the heart valves.- Lower rejection rate.- Less risk of blood clots in mechanical heart

valves.- Remove the need for blood thinning medication.- Implant the artificial heart valves through a less

intrusive method (currently open-heart surgery).

References• "Artificial Heart Valve." Wikipedia. N.p.. Web. 14 Oct 2012.

<http://en.wikipedia.org/wiki/Artificial_heart_valve>• "Biological Heart Valves." Cedars-Sinai. N.p., n.d. Web. 14 Oct 2012.

<http://www.cedars-sinai.edu/Patients/Programs-and-Services/Heart-Institute/Centers-and-Programs/Cardiothoracic-Surgery-Services/Heart-Valve-Repair-and-Replacement/Biological-Heart-Valves.aspx;

• Dance, Amber. "Slide Show: 7 Artificial Valves That Lend Hearts a Helping Hand." Scientific American. 25 2009: n. page. Web. 14 Oct. 2012. <http://www.scientificamerican.com/article.cfm?id=artificial-heart-valves>

• "Mechanical Heart Valves." cedars-sinai. N.p., n.d. Web. 14 Oct 2012. <http://www.cedars-sinai.edu/Patients/Programs-and-Services/Heart-Institute/Centers-and-Programs/Cardiothoracic-Surgery-Services/Heart-Valve-Repair-and-Replacement/Mechanical-Heart-Valves.aspx;

• "Mechanical Heart Valve." drexel.edu. N.p., 17 2008. Web. 14 Oct 2012. <http://www.pages.drexel.edu/~nag38/History.html>