Artificial hearts are used for replacing the original biological heart when the biological heart is failing and can no longer be used.  The artificial heart is very useful as it helps for people who are on a waitlist for a transplant, the artificial heart can buy them time and/or they can give it to someone else in the meantime.  Unfortunately, the artificial heart does not last very long, around five years max, usually less. It is mainly there just to help with the very long wait of the transplant list. It seems strange that the artificial heart can’t last long because essentially the heart just a big pump in the human body, but “it embodies complex subtleties that defy straightforward emulation using synthetic materials and power supplies.” (ScienceDaily, 2019).

 

A real heart: 

 

In order to understand how an artificial heart works, we first need to understand how a regular biological heart functions.  A human heart consists of two atria and ventricles, so essentially four chambers. The right atrium (top right of heart) collects the deoxygenated blood from the body, it gets pushed into the right ventricle and then the deoxygenated blood is pushed to the lungs to be oxygenated.  The blood comes back from the lungs to the left atrium of the heart, pushed to the left ventricle and from there the blood gets pumped to the rest of the body. “Artificial hearts can now completely, if temporarily, replace the ventricles and valves with a device made of plastic or other man-made materials, which does the job of pumping blood around.” (Physics, 2019).   There are two kinds of artificial hearts: internal and external.

 

External:

 

A possible external heart produced by Syncardia Systems “works by using a pump carried externally in a backpack.” (nhs.uk, 2019).  This portable artificial heart implant is temporarily “designed to keep pumping blood to vital organs until a suitable donor heart is found….is said to provide the body with an immediate blood flow of up to 9.5 litres a minute.” (nhs.uk, 2019).  This particular device is meant to replace the ventricles.  The ventricles are removed from the patient and replaced with artificial (plastic) ventricles and plastic tubes are used for the valves of the ventricle.  In these ventricles are balloon-like sacs that expand and condense just a regular heart does. Pulse of air to these sacs forces out the blood from the heart.  These pulses come from the pump and power supply carried outside the body and sent through tubes that go through the skin.

Syncardia artificial heart:

 

In 2011, a 40 year-old-man in the UK received this heart.  He had been suffering from end-stage heart failure and the symptoms seemed to go away after getting the device.



Internal:

 

A possible internal heart produced by AbioMed uses “an internal pump and battery which can be charged...transferring power under the skin without having to penetrate it….an electronics package is implanted in the abdomen of the recipient of the transplant to monitor and control the pumping of the heart.” (Physics, 2019).    With this method, a magnetic field is created with an external power supply with a wire attached.  A wire implanted under the skin influences the voltage from the external power supply to power the heart.  There are a few complications with this though, making sure the right amount of power is supplied (too much power will create heat and damage surrounding skin) and making sure that it fits comfortably in the body.   

 

AbioMed Artificial Heart:

 

Monitoring:

 

Monitoring blood flow in the artificial heart is important because of what your heart is doing.  When you are doing exercise, for example, your heart is pumping faster to get more blood through the body.  Ultrasound is used to monitor the blood flow. “They bounce high-frequency sound waves off the blood cells coming out of the heart, the volume and speed can be measured using similar basic principle to those behind radar.” (Physics, 2019).  



Finding the right material:

 

Scientist were working with silicone to try and make a softer, longer lasting artificial heart.  Silicone is a soft material and is used in many implants. It can “mimic the material properties of human tissue to a certain extent.” (Healthline, 2019).  The idea was to do a scan of a patient’s heart and then make a mould using a 3D printer for making the silicone heart.  The silicone heart would then be designed to act as a real heart does. Unfortunately, the silicone heart only lasted 3,00 heartbeats before collapsing.  The scientists are trying other materials with similar methods, in hopes they can create an artificial heart that can last a lifetime.



Bibliography:

 

 

 

 

Original Post

Add Reply

Post
×
×
×
×