Wednesday, December 28, 2011

Total Artificial Heart Surgery

A total artificial heart (TAH) is a device that replaces the two lower chambers of the heart. These chambers are called ventricles. You may benefit from a TAH if both of your ventricles don’t work due to end- stage heart failure.
Heart failure is a condition in which the heart is damaged or weakened and can’t pump enough blood to meet the body’s needs. “End stage” means the condition has become so severe that all treatments, except heart transplant, have failed.  
You may need a TAH for one of two reasons:
• To keep you alive while you wait for a heart transplant
• If you’re not eligible for a heart transplant, but you have end stage heart failure in both ventricles

     The TAH is attached to your heart’s upper chambers—the atria. Between the TAH and the atria are mechanical valves that work like the heart’s own valves. Valves control the flow of blood in the heart. Currently, there are two types of TAH. They’re known by their brand names: the Cardio West and the AbioCor. The main difference
Excerpted from “Total Artificial Heart,” by the National Heart, Lung, and Blood Institute (NHLBI,, part of the National Institutes of Health, September 2008.
between these TAHs is that the Cardio West is connected to an out- side power source and the AbioCor isn’t.

     The Cardio West has tubes that, through holes in the abdomen, connect from inside the chest to an outside power source. The AbioCor TAH is completely contained inside the chest. A battery powers this TAH. The battery is charged through the skin with a special magnetic charger.
Energy from the external charger reaches the internal battery through an energy transfer device called transcutaneous energy trans-mission, or TET.
An implanted TET device is connected to the implanted battery. An external TET coil is connected to the external charger. Also, an implanted controller monitors and controls the pumping speed of the heart.
A TAH usually extends life for months beyond what is expected with end-stage heart failure. If you’re waiting for a heart transplant, a TAH can keep you alive while you wait for a donor heart. It also can improve your quality of life. However, a TAH is a very complex device.
It’s challenging for surgeons to implant, and it can cause complications. Currently, TAHs are used only in a small number of people. Researchers are working to make even better TAHs that will allow people to live longer and have fewer complications.
Other Names for a Total Artificial Heart
• Artificial heart
• AbioCor
• CardioWest
When a Total Artificial Heart Is Needed
You may benefit from a total artificial heart (TAH) if both of your ventricles don’t work due to end-stage heart failure. If you’re waiting for a heart transplant, a TAH can help you survive longer. It also can improve your quality of life. If your life expectancy is less than 30 days and you’re not eligible for a heart transplant, a TAH may extend your life beyond the expected 30 days.
A TAH is a “last resort” device. This means only people who have tried every other type of treatment, except heart transplant, can get it. The TAH isn’t used for people who may benefit from medicines or other procedures.
TAHs also have a size limit. These devices are fairly large and can only fit into large chest areas. Currently, no TAHs are available that can fit into children’s chests. However, researchers are trying to make smaller models.
The United States Food and Drug Administration (FDA) has approved the TAH for certain types of patients. Your doctor will discuss with you whether you meet the conditions for getting a TAH.
If you and your doctor decide that a TAH is a good option for you, you also will discuss which of the two types of TAH will work best for you.
What to Expect before Total Artificial Heart Surgery
Before you get a total artificial heart (TAH), you will likely spend at least a week in the hospital to prepare for the surgery. You might already be in the hospital getting treatment for heart failure.
During this time, you will learn about the TAH and how to live with it. You and your loved ones will spend time with your surgeons, cardiologist (heart specialist), and nurses to make sure you have all the information you need before surgery. You can ask to see what the de-vice looks like and how it will be attached inside your body.
Your doctors will make sure that your body is strong enough for the surgery. If your doctors think your body is too weak, you may need to get extra nutrition through a feeding tube before surgery.
You also will have tests to make sure you’re ready for surgery. These tests include the following:
• A chest CT scan: This test is used to make sure the TAH will fit in your chest. Current TAHs are fairly large. Before you have surgery, your doctor will make sure there’s enough room in your chest for the device.
• Blood tests: These tests are used to check how well your liver and kidneys are working. Blood tests also are used to check the levels of blood cells and important chemicals in your blood.
Chest x-ray: This test is used to create pictures of the inside of your chest to help your doctors prepare for surgery.
EKG (electrocardiogram): This test is used to check how well your heart is working before the ventricles are replaced by the TAH.
What to Expect during Total Artificial Heart Surgery
Total artificial heart (TAH) surgery is complex and can take be-tween 5 and 9 hours. It requires many experts and assistants. As many as 15 people may be in the operating room during surgery.
The team for TAH surgery includes the following:
• Surgeons who do the operation
• Surgical nurses who assist the surgeons
• Anesthesiologists who are in charge of the medicine that makes you sleep during surgery
• Perfusionists who are in charge of the heart-lung machine that keeps blood flowing through your body while the TAH is put in your chest
• Engineers who are trained to assemble the TAH and make sure it’s working properly
Before the surgery, you’re given anesthesia to make you sleep. During the surgery, the anesthesiologist checks your heartbeat, blood pressure, oxygen levels, and breathing. A breathing tube is placed in your windpipe through your throat. This tube is connected to a ventilator (a machine that helps you breathe).
A cut is made down the center of your chest. The chest bone is then cut and your ribcage is opened so that the surgeon can get to your heart.
Medicines are used to stop your heart. This allows the surgeon to operate on your heart while it’s not beating. A heart-lung machine keeps oxygen-rich blood moving through your body.
The surgeons remove your heart’s ventricles and attach the TAH to the upper chambers of your heart. When everything is attached properly, the heart-lung machine is switched off and the TAH starts pumping.
What to Expect after Total Artificial Heart Surgery
Recovery in the Hospital
Recovery time after total artificial heart (TAH) surgery depends a lot on your condition before the surgery.
If you had severe heart failure for a while before getting the TAH, your body may be weak and your lungs may not work very well. Thus, you may still need a ventilator (a machine that helps you breathe) after surgery. You also may need to continue getting nutrition through a feeding tube.
Your hospital stay could last a month or longer after TAH surgery. Right after surgery, you’ll be in the hospital’s intensive care unit. An intravenous (IV) line will be inserted into a vein in your arm to give you fluids and nutrition. You’ll also have a tube in your bladder to drain urine.
After a few days or more, depending on how quickly your body re-covers, you’ll move to a regular hospital room. Nurses who have experience with TAHs and similar devices will take care of you.
The nurses will help you get out of bed, sit, and walk around. As you get stronger, you’ll be able to go to the bathroom and have a regular diet. The feeding and urine tubes will be removed. You’ll also be able to take a shower. You’ll learn how to do this while taking care of your TAH device.
Nurses and physical therapists will help you gain your strength through a slow increase in activity. You’ll also learn how to care for your TAH device at home.
Having family or friends visit you at the hospital can be very helpful. They can help you with various activities. They also can learn about caring for the TAH device so they can help when you go home.
Going Home
Activity level: When you go home after TAH surgery, you’ll likely be able to do more activities than you could before. You’ll probably be able to get out of bed, get dressed, and move around the house. You may even be able to drive. Your health care team will advise you on the level of activity that’s right for you.
Bathing: If you have an AbioCor TAH, you can shower or swim, as long as the device is charged.
If you have a Cardio West TAH, you will have tubes connected to a power source outside of your body. The tubes go through an opening in your skin. This opening can let in bacteria and increase your risk for infections.
You will need to take special steps before you bathe to make sure the tubes going through your abdomen don’t get wet. Your health care team will explain how to do this.


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