Total Artificial Heart (TAH) Implant: What to Know
Medically reviewed by Richard N. Fogoros, MDMedically reviewed by Richard N. Fogoros, MD
A total artificial heart (TAH) is a mechanical heart-like device that acts as a pump when placed into the chest. It is used to replace the pumping action of the damaged heart ventricles while a person waits for a heart transplant.
Other heart pumps, such as the left ventricular assist device (LVAD), can support a damaged ventricle (typically the left ventricle). In contrast, the total artificial heart is designed to replace both the left and right ventricles entirely. Sometimes, a total artificial heart will be used if an LVAD system fails.
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Total Artificial Heart: What’s It Made From?
The heart has ventricles, which are two lower chambers designed to help receive and pump blood throughout the body. They receive blood from the upper chambers, known as the atria, and pump it to the rest of the body to keep circulation going. The right ventricle helps pump blood to the lungs, whereas the left works to keep blood flowing to the rest of the body.
When both the right and left ventricles become irreversibly damaged, the total artificial heart can sometimes replace the damaged ventricles. This material is durable, flexible, and can act similarly to heart muscle tissue.
There is one approved total artificial heart approved in the United States, the SynCardia Total Artificial Heart System.
Controlling the TAH
Once in the chest, a machine located on the outside of the body, known as a driver, controls the pump to essentially take over the action of the heart, making it pump blood the same way as a healthy heart.
TAH vs. LVAD
Device Differences
In those with damage to both sides of the heart, a total artificial heart replaces the left and right ventricles, whereas an LVAD only works on the left ventricle. A total artificial heart may also be used if a person has an LVAD and fails to perform.
They are often made of the same material, and both have drivers that help to keep blood circulation at adequate levels but function somewhat differently.
A total artificial heart works by delivering air pulses through tubes known as cannulas. These air pulses inflate and deflate flexible diaphragms within the device, creating a pumping action that produces adequate blood circulation.
In contrast, an LVAD uses a battery-powered pump that continuously pumps blood by pulling it from the left ventricle before pushing it into the aorta to be sent to the rest of the body.
Patient Eligibility
Typically, a total artificial heart is used as a bridge to transplant for those who require a heart transplant. It works as a temporary sustaining device. It is considered for patients who have end-stage heart diseases, such as:
Irreversible biventricular failure
Allograft failure
Organ (heart) transplant rejection
Massive heart attack
Uncontrollable ventricular arrhythmia
End-stage complications from congenital (present at birth) heart defects
Blood clots in the lining of the blood vessels and heart
Effect on Life Expectancy
Once a person has recovered from surgery for a total artificial heart, they can return to their daily life while they await a heart transplant. During that time, they must be mindful of their device to maintain its integrity. Since a total artificial heart is designed to keep the heart working until a heart transplant is available, they are built only for temporary use.
People with a total artificial heart have a short window of time to use the total artificial heart before getting a transplant, and less than 60% will live for a year after their total artificial heart surgery if a heart does not become available in that time.
Cost Associated With TAH
Total artificial heart surgery is expensive and not very affordable for the average person. The cost range can be over half a million dollars for the procedure.
Implantation Process
A person who needs a total artificial heart will have to have cardiac surgery. It is done in steps:
A breathing tube is placed in the windpipe during surgery to help you breathe, as you will be under anesthesia at the time.
A cut is made into the chest bone to open the sternum up so that medicines to stop the heart can be administered.
While stopped, a heart-bypass machine is used to keep blood flowing throughout the body.
The ventricles of the heart are removed, and the TAH is implanted and attached to the upper chambers, aorta, and pulmonary artery.
Once attached, the heart bypass machine is turned off, and the TAH pump is started.
For the first 24 hours after surgery, the chest remains open to ensure it’s working correctly before closing it up.
Risks of TAH Surgery
There are various risks associated with total artificial heart surgery, including:
Abnormal bleeding in the chest
Infections
Death
Kidney infections or failure
Reduced quality of life due to lifestyle changes that are needed while the total artificial heart is implanted
Read Next: Artificial Heart Implant is the First of its Kind in the U.S.
Life With an Artificial Heart
Once you have recovered, you can slowly increase your activity levels while being mindful of what you eat and how you move to keep the artificial heart working as it should.
Because the total artificial heart is designed to provide adequate blood circulation, you may be able to do more activities than you could before getting it, such as moving around the house comfortably, getting out of bed, or driving.
You will also need ongoing care while you have a total artificial heart, which can include:
Going to regular checkups that could include blood tests and heart function tests.
Taking medication as prescribed to prevent blood clots or infections.
Changing your lifestyle by eating healthier, being more physically active, managing stress, and getting enough quality sleep.
Protecting Your Heart With a TAH
After surgery, you may also be required to participate in cardiac rehabilitation, a supervised program that includes exercises, counseling, and learning about what and what not to eat.
Related: Heart Healthy Foods: What to Eat and What to Avoid
Pathway to Being a Heart Transplant Recipient
Not everyone qualifies for a heart transplant, so not everyone will be able to get a total artificial heart in the event they experience end-stage heart disease. To qualify, you must be:
Younger than 70
Have health insurance or the funds to pay for both the total artificial heart and heart transplant
Be free of any health conditions that could delay or prevent you from getting a heart transplant, including active cancer, uncontrolled diabetes, drug or alcohol misuse, and obesity
Before being put on a list for a heart transplant, you will need a referral from your heart specialist. You will also be required to go through an educational period where you learn everything there is to know about the transplant, what to expect afterward, and how to take care of yourself after the surgery.
Medical tests will be conducted to determine your eligibility as well, such as:
Blood type and antibody testing to find an organ donor match
Cancer screenings
Dual-energy X-ray absorptiometry (DEXA) scans to ensure your bone density is adequate
Kidney function tests
Tests to check for diabetes
Imaging tests that check for issues with other organs and blood vessels
Lung function tests
Right heart cardiac catheterization to check the pressure in the lungs
Immunity tests to check how well the body protects against vaccine-preventable diseases
Once approved for a heart transplant after meeting all the criteria, you will be put on a waiting list.
Related: Heart Disease Causes and Risk Factors
Summary
A total artificial heart is a polyurethane device designed to mimic the action of the heart's left and right ventricles. It helps the heart pump adequate blood through the body while someone waits for a heart transplant due to end-stage heart conditions.
The surgery is intensive and involves recovery time. Still, once that period is over, a person with a total artificial heart can return to their daily lives, keeping in mind heart-healthy lifestyle changes to ensure that they are as healthy as possible while they wait for a donor.
Not everyone qualifies for a total artificial heart. Thus, people must go through an extensive qualification process before being put on a waiting list for a heart transplant and getting a total artificial heart. Fewer than 60% of people with a total artificial heart will live longer than a year after getting it, so for them, getting an organ quickly is of the utmost importance.
Read the original article on Verywell Health.
