In this post, I will be talking about the two different types of prosthetic valve replacements: artificial valve replacements and biological valves replacements.  I will be talking about the advantages and disadvantages to both, as well as what types there are.




Problems with heart valves, such as mitral and aortic valve disease, sometimes need to be replaced by either an artificial (also known as metal or mechanical) valve or biological (also known as tissue) valve.  The two most common mechanical valves are tilting-disc and bileaflet.  Different options for biological valves include, autograft valves (another valve from the patient's heart is used as a replacement), homograft valves (a valve from the deceased) and heterograft valves (comes from an animal such as a pig).  


Tilting-disc mechanical heart valve:


Advantages of Mechanical valves and disadvantages of biological valves:


One advantage of the artificial valve is that it lasts longer than a biological valve.  An artificial valve last 20-30 years, while a biological valves lasts 10-15 years. Artificial valves also tend to be more durable.  Infections (like endocarditis) are common after a biological prosthetic heart valve replacement. These biological heart valve replacements seem to have higher risk of infection than mechanical heart valve replacements. “The risk of infection in the artificial valve was about 50% higher with biological prosthesis than with a mechanical.”  (ScienceDaily, 2019).


Advantages of biological valves and disadvantages of Mechanical valves:


“The blood flow around the mechanical valve results in high sheer stress, our own clotting defense mechanisms can contribute to a higher risk for” (, 2019) blood clots inside a blood vessel (which will stop the flow of blood through the circulatory system) and all in good time, an obstructed artery.  Because of this, patients must be on anticoagulant medication for the rest of their life, like a vitamin K such as Warfarin. Also with this there is a “higher risk of bleeding complications associated with anticoagulants. Bleeding risk increases with age.” (, 2019). Another disturbing thought is that Warfarin is used to kill rats, very strong stuff, but it is still commonly used as medication (no need to worry...too much).  If a patient is on other medication while taking Warfarin it may mess things up.


Bileaflet mechanical valve:


The Decision:


Really it comes down to the age of the patient and what their needs and wants are when choosing between an artificial or biological valve.  A general recommendation when it comes to age is patients younger than 60/65 can receive a mechanical valve (because mechanical lasts longer) and patients older than 60/65 can receive a biological valve (this is a recommendation though, either one can still be done).  Another thing that can make up a young woman's mind about which one to choose is pregnancy. Warfarin should not be used during pregnancy, so a biological heart valve may be a better option then. It is a hard decision to make, a 50% chance of infection with a biological heart valve or Warfarin for the rest of your life with a mechanical heart valve.


I know the  last time I said I was going to look into artificial hearts or pancreases for this round, but I changed my mind and will do that for next time.  That is if I don’t get steered off in another direction again.




Original Post

 Hi Haley! 

 Great round of research, I like how you looked at the advantages and disadvantages of both biological and artificial heart valves. I think it's interesting how doctors can replace a heart valve of a human with a heterograft valve, like one from a pig or something, as well as using a homograft valve. It's interesting how deceased people's organs can still be donated to living people in need of new organs.

 I'm wondering, do you think a biological or mechanical heart valve would be safer or more effective. Aside from pregnant women or people who are taking certain medications, there are advantages and disadvantages to both types with each person, like you mentioned; age, pre-existing medical conditions, etc. 

 I'm also interested to see what you find regarding artificial pancreases. Here's some sites that may help you:

 Good luck! 

Hi Haley!

Great round of research, i found it very interesting and think you did a great job making this easy to understand yet still very technical. I also liked how you compared biological and mechanical prosthetic hearts.

Regarding artificial pancreases, maybe you could do a similar comparison (that is, if there are different types of pancreases). Or, you could compare the effects of pancreas replacement to those of a heart replacement. Just some ideas! I'm excited to see where you take your research.


Hi Haley,

Great round of research! Your post was very detailed and informative. It was really interesting to read, especially as my grandma has a biological prosthetic heart valve, something I just learned a few minutes ago actually. I think that it's good that you looked at the topic through multiple lenses, considering both disadvantages and advantages of both mechanical and biological prosthetic heart valves. In the end, as you said, I think it comes down to the individual patient's needs and wants based on factors such as age and pregnancy. 

Here are some websites you might find useful for your research on artificial hearts and pancreases:

Good luck!

Hi Haley,

Congratulations on another fantastic research round. I really enjoyed the photos you added and how you laid out your information. I particularly liked how you explained the differences between the mechanical valves and biological valves. It was well done!

It's crazy how science is changing the world. When you were talking about the efficiency of mechanical valves, I couldn't help but question whether, in the future, there would be a potential where people (with healthy biological hearts) would opt to have mechanical valves just because it is much better and more efficient? I find that very interesting, and something you may potentially be intrigued into investigating...

Nevertheless, I also found out that, recently, scientists have created a heart tissue that can beat on its own. They used stem cells to create this. However, it's actually to weak to pump blood on its own, but there is a lot of potential to where this is going. I suggest that maybe you would want to look into different ways and materials scientists are using to replace our body parts.

Once again, great work!

Here are some sites you may be interested in looking into:


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