What is an artificial heart? (Artificial heart) Ventricular assist device ?
An artificial heart is a device that replaces the heart that can take over the job of pumping blood instead of the patient's heart for a period of time. That is, it is an alternative cardiac system that is installed to help the normal heart. Therefore, the artificial heart can be used in severe cases where the patient's heart is unable to supply the body with sufficient blood.
Temporary artificial hearts are being implanted to gain time during Heart transplantation. Most artificial hearts are cardiac assist pumps, which are known in English as a VAD (ventricular assist device).
An artificial heart should not be confused with a heart-lung machine, which is a larger device used, for example, when performing open heart surgery.
When is the artificial heart used? (Artificial heart)?
The artificial heart is initially used to buy time during heart transplantation in a patient with severe heart disease.
A heart transplant is a last resort if treatment with medications and other procedures is no longer successful.
These patients are in the last stage of the disease, with life expectancy usually dropping to less than a year.
Also, when the heart's pumping ability becomes so weak that the patient is at risk of dying in a short time, the heart and artificial hearts can be used as a permanent way to replace the heart in severe cases (as a pump to support the heart).
There can also be severe cases such as Congestive heart, which calls for an artificial heart.
Heart failure can be caused by heart abnormalities, narrowing of the coronary arteries (CHD, coronary heart disease), or hypertrophic cardiomyopathy.
Sometimes mechanical circulatory support is used to help the heart recover.
The goal is always that at some point the heart will be able to function on its own again.
How does an artificial heart work?
As a rule, today's artificial hearts are pumping systems that capture a large portion of what the heart produces. That is, they are supportive pumps of the heart.
The artificial heart is called (VAD), which is an abbreviation of the English language for (Ventricular Assist Device).
Most of the time, a left ventricular pump (LVAD) must be used so that adequate amounts of blood can be supplied to the body's circulatory system.
But there are also right ventricular support devices (RVAD), which ensure pulmonary blood flow to both ventricles (BVAD).
The artificial heart is usually placed in the abdominal wall. With the remaining normal weak heart also contributing to the pumping function.
The artificial pump is first connected to the heart and to the main artery (aorta) through plastic tubes.
If not, the LVAD system is connected to other parts of the heart and blood vessels accordingly.
By means of a pump mechanism, the device transports blood from the heart chamber to the blood vessels and thus to the organs and tissues.
There are many other types, some with different pumping methods.
Some devices have a pulsating blood pump and others have a continuous blood pump (eg with a small turbine). The pump system is battery operated.
It is electronically controlled and monitored. The cable runs through the skin and is connected to the controller.
In addition to these systems, there are also other variants, for example fully implantable artificial hearts that lie completely in the body.
It is only suitable for adults with large breasts, because it takes up a lot of space in the body.
Rarely, a true replacement heart (TAH), that is, a pump that resembles a human heart, is used in place of the heart that has been removed.
What are the tests that are done before implanting an artificial heart?
Various medical tests are performed to diagnose heart disease.
This includes a medical history and physical examination.
It is also necessary to take blood tests, blood pressure measurements, andElectrocardiogram determination of long-term values, and imaging tests such as ultrasound and X-rays.
Further tests must also be done to put the patient on the waiting list for a heart transplant.
How is an artificial heart implanted?
The implantation of the artificial heart is performed under general anaesthesia.
The chest and abdomen are opened to access the heart. Then a pocket is created under the abdominal wall, as well as an opening for the cable.
The heart and lungs system is connected to the circulatory system so that the body is supplied with oxygen-rich blood for the duration of the procedure.
A hole is made in the heart chamber through which the feeding tube of the artificial heart system is inserted.
The heart is sutured around the tube. Then a drainage tube is placed into the main artery (aorta).
The pump is then inserted into the abdominal pocket. The heart-lung machine can be separated once the artificial heart is in operation. The chest and abdominal walls are closed again and a bandage is placed on them.
Possible complications from surgery
An artificial heart transplant can lead to serious complications. Primary bleeding, secondary bleeding and infection, as well as wound and scar healing disorders are possible.
Life can become life-threatening pericardium Or infection in the body cavities, and the places where the cables protrude from the body are at risk of infection as well.
Blood clots can develop due to implantation of an artificial heart.
Vascular blockages can also occur and the blood supply to organs is compromised. It is very rare for the pumping technique to fail.
After the operation, the patient is transferred to the intensive care unit, and then to the regular hospital ward. He receives appropriate physical therapy so that he can move normally and independently again.
The patient learns from the medical staff how to deal with the artificial heart. He has to come to terms with the fact that he has to carry a monitor and a cable that leads to the artificial heart with him outside the body. The patient should be very careful when washing and showering, and the device should not come into contact with water. The cable can be wrapped in the leather. The patient is given anticoagulant drugs most of the time.
After the hospital stay, the patient should go for a checkup regularly, usually one day a week.
Chances of success of the artificial heart
The heart pump improves blood flow in the body and thus ensures that the organs are adequately supplied with oxygen and nutrients.
The heart muscle will not have to pump as hard and will relax greatly.
But in the long run, the artificial heart cannot be a good substitute for the human heart, even though more than one patient has lived with the device for several years.
It is possible that blood pumps and associated therapies will be better developed in the future. Then a heart transplant can be dispensed with.
An artificial heart operation is usually performed at a time when some other organs are damaged due to a weakened heart (such as the kidneys). Thus, the surgical risks are higher compared to the operations performed on healthy patients.
It often takes longer than usual for patients to recover from the operation.
The process of getting used to the artificial heart often takes weeks.
The patient can spend a significant part of the time at home and, to some extent, do normal activities (housework, walking, cycling, work).
Frequently asked questions about artificial heart transplantation
How many artificial hearts have been implanted to date?
Nearly 1,700 artificial hearts have been implanted worldwide. Similar to a heart transplant, an artificial heart replaces both failing heart ventricles and each of the heart's original four valves.
Who invented the artificial heart?
Dr. and American inventor Paul Winchell, is the person who is fully credited with inventing the artificial heart and patented a mechanical artificial heart that can be implanted in the chest cavity.
When was the first implantation of the artificial heart?
In 1982, the first artificial heart transplant was performed on a 61-year-old patient named Barney Clark by surgeons at the University of Utah. Cardiologist Willem Kolff led the work team.