What’s an artificial heart?

[ad_1]

The creation of an artificial heart that would be a successful long-term replacement for the human heart has been a goal of medical research for several decades. So far, various doctors and scientists have developed some machines that can take over heart function while a patient waits for a transplant, or for people who cannot receive transplants. These mechanical hearts can be inserted into the body, so many people can have a life extension, but they don’t last forever.

Before delving into the history of the artificial heart, it’s important to understand what it is and what it isn’t. This mechanized device is not a heart/lung bypass machine. However, these machines represent an extremely important development in medicine and are used regularly.

Artificial hearts should be viewed as distinct from ventricular assist devices and left ventricular assist devices (VADs and LVADs). These can be implanted to take over some of the work of a heart that maintains a certain amount of function. They are also useful for bridging the gap when patients are on a transplant waiting list and can help the heart keep working at a more efficient pace over a period of time. However, it should be understood that a real artificial heart is implanted in the body and takes over the work of the weak heart. The term failure usually means that neither the left nor the right ventricle can function well enough to sustain life.

In the mid-20th century, there were several people working on creating an artificial heart, and the first implant was performed on a dog in 1957. It wasn’t hugely successful, and the dog survived only a few hours after the implant. Research into fully mechanized hearts continued in dogs, and in the mid-1960s, physicians began developing LVADs as well, with the first successful LVAD surgery performed in 1966.

Much trial and error followed, and some of the major concerns included the rejection of various components of the artificial hearts and the survival rate, which was considerably low for both LVADs and total hearts. Two artificial hearts were developed in the 1980s and continue to be used. These are the Jarviks and the Abiocors. Both have been used in many surgeries to prolong life. Abiocor was considered an improvement over Jarvik because its energy source was not outside the body. Jarvik requires external wiring to a power source, but in long clinical trials it has been shown to be more effective than Abiocor with longer survival rates for some patients.

Another artificial heart developed in the 2000s that shows great promise was created by Dr. Alain Carpentier of France, and this heart is being tested to determine efficacy and safety. Unlike its predecessors, Carpentier’s model uses some animal tissue in its design, which could prove effective in reducing rejection. Other scientists continue to work on additional models, as while some patients survive for several years after receiving an artificial heart, others still do not. For some survivors, quality of life may be poor and life span may be short.
There are some concerns inherent in making artificial hearts. One that remains is how to fuel the heart, and improvement in various energy cells may eventually dispel these concerns. Yet a human heart must work constantly and even with advanced power techniques, it’s hard to know how long an artificial heart can last, once in the body. However, there is still a great deal of need for artificial hearts because some people are ineligible for heart transplants, and others need them and die waiting for a heart.

There is some speculation that advances in regenerative medicine would eventually make the search for the perfect artificial heart obsolete. There is hope that one day scientists will be able to use a patient’s tissue to grow a new heart for those who need it. This would eliminate the concern about rejection and address the lack of transplants to meet demand.

[ad_2]