Good morning! Today I’m going to talk about artificial heart as one of the most significant invention in the history of humanity. An artificial heart is a device that replaces the heart. Artificial hearts are typically used to bridge the time to heart transplantation, or to permanently replace the heart in case heart transplantation is impossible. Since the late nineteenth century, scientists have tried to develop a mechanical device that could restore oxygen to the blood and remove excessive carbon dioxide, as well as a pump to temporarily supplant heart action.
Perhaps the most famous scientist is Dr. Robert Jarvik, who invented in 1982 an artificial heart called the Jarvik-7. This device, made from aluminum and plastic, replaced the two lower chambers of the natural heart and used two rubber diaphragms for the pumping action. An external compressor the size of a refrigerator kept the artificial heart beating. Barney Clark was the first patient to receive this heart. He survived 112 days before physical complications caused by the implant took his life.
In 1986, William Schroeder became the second Jarvik-7 recipient, surviving for about 20 months. The medical community realized that a completely implantable heart could avoid the mobility and infection problems caused by the Jarvik-7. In 1988, the National Institutes of Health began funding development of such hearts and was supporting such a program in 1991 totaling $6 million. Three years later, an electric and battery-powered implantable LVAD became available. In 1999, Charlie Chappis became the first patient ever released from a hospital with such a device.
In August 2006, an artificial heart was implanted into a 15-year-old girl at the Stollery Children’s Hospital in Edmonton, Alberta. It was intended to act as a temporary fixture until a donor heart could be found. Instead, the artificial heart (called a Berlin Heart) allowed for natural processes to occur and her heart healed on its own. After 146 days, the Berlin Heart was removed, and the girl’s heart was able to function properly on its own. On December 16, 2011 the Berlin Heart, a ventricular assist intended for children age 16 and under, gained U. S.
FDA approval. The device has since been successfully implanted in several children including a 4-year-old Honduran girl at Children’s Hospital Boston. In 2012, a study published in the New England Journal of Medicine compared the Berlin Heart to extracorporeal membrane oxygenation (ECMO) and concluded that “a ventricular assist device available in several sizes for use in children as a bridge to heart transplantation was associated with a significantly higher rate of survival as compared with ECMO. The study’s primary author, Dr.
Charles D. Fraser, Jr., surgeon in chief at Texas Children’s Hospital, explained: “With the Berlin Heart, we have a more effective therapy to offer patients earlier in the management of their heart failure. When we sit with parents, we have real data to offer so they can make an informed decision. This is a giant step forward. Nowadays every year in the United States, there are 50,000 persons in need of a heart transplant. There are on average 2,400 donor hearts available. What are the options available for the remaining 47,000 plus individuals that do not receive a transplant?
The artificial heart is able to replace the damaged heart of some of these individuals if they are able to meet certain clinical specifications. The artificial heart is able to prolong life until a heart transplant can be obtained when no other options exist for the patient and life expectancy is predicted to be less than 30 days. Advantages of the artificial heart are that it is readily available and there is no need for immunosuppressive drugs, which can compromise renal function and leave the patient susceptible to infection.
Patients who qualify for artificial heart programs are likely already suffering from organ damage or stress, due to the heart’s impaired ability to pump efficiently. The decreased blood flow that results impairs function in vital organs such as the liver, kidney, and brain. The artificial heart restores hemodynamic stability, raising blood pressure and helping vital organs recover, as much as possible, in preparation for a heart transplant.
For persons who are not heart transplant candidates, the artificial heart has allowed prolonged time with family and friends, and time to enjoy desired activities. Patients can even go home with a fully implanted artificial heart. Disadvantages The artificial heart is not without risk, and those risks include wearing out or failure of the electrical motor, infection, and the need to take blood thinners to prevent clotting. Stroke and bleeding are also possible complications with the artificial heart.
Another disadvantage of the artificial heart is that not all patients have a body size that allows the device to be implanted into the chest cavity, making small persons unable to receive the device. Finally I want to say that the artificial heart may not be the answer for every patient, but for some patients it is the bridge that leads them back from nowhere. Medical technology continues to improve as researchers refine the artificial heart and attempt to make it an option for more patients.