Artificial heart put in human
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Two surgeons removed the patient's dying heart Monday at the Jewish Hospital in Louisville and implanted the mechanical heart, a yo-yo-shaped, two-chambered plastic-and-titanium pump weighing less than 2 pounds that is powered through the skin by an external battery pack.
The patient had been expected to die within a month without the operation, and doctors said they expect the artificial heart to extend the person's life by only a month.
But some consider the device a major step toward improving patients' quality of life.
The new pump, called the AbioCor, is also a technological leap from the mechanical hearts used in the 1980s, which were attached by wires and tubes to bulky machinery outside the body. The most famous of those, the Jarvik-7, used air as a pumping device and was attached to an apparatus the size of a washing machine.
"I think it's potentially a major step forward in the artificial-heart development," said Dr. David Faxon, president of the American Heart Association.
However, he said the dream of an implantable, permanent artificial heart is not a reality: "This is obviously an experimental device whose long-term success has to be demonstrated."
Only about half of the 4,200 Americans on a waiting list for donor hearts received them last year; most of the rest died.
The hospital did not identify the patient by name or sex, in keeping with a previous agreement to withhold information for an unspecified "quiet period."
A hospital statement said the patient was "resting comfortably."
New debate
The implant marked the first significant advance in nearly 20 years in an often stormy quest marked by great excitement about the artificial heart's potential and bitter disappointment when it became clear the technology was prolonging suffering instead of saving lives.
Today the debate has changed.
Some experts praised the new device because it is totally enclosed in the body, sharply reducing the risk of infection, a crucial shortcoming of earlier efforts.
But other experts suggested new technologies, including implantable heart-assist devices, advanced surgical techniques and medications, had made artificial hearts a needless alternative in all but a handful of cases.
Robert Jarvik, whose Jarvik-7 heart kept William Schroeder, of Jasper, Ind., alive for 620 days in the mid-1980s in an episode regarded by many Americans as an unsightly ordeal, dismissed the technology he helped pioneer as "obsolete" and described the new device as "false hope and a sincere, but misdirected effort."
The first recipient of the Jarvik-7, retired Des Moines, Wash., dentist Barney Clark, lived 112 days after receiving it in 1982.
Five hospitals
The AbioCor was developed by Abiomed, of Danvers, Mass., which said in April that the company had gotten permission from the Food and Drug Administration to implant its AbioCor heart in at least five individuals at any of five hospitals around the country.
Besides Jewish Hospital, the other participants include Brigham and Women's Hospital, teamed with Massachusetts General Hospital in Boston; Hahnemann University Hospital in Philadelphia; the Texas Heart Institute in Houston; and the UCLA Medical Center in Los Angeles.
Candidates for the implant must be ineligible for transplant and have "end stage" heart disease so grave that death is anticipated within a month, company president David Lederman said.
He cautioned that even with the implant, "every single patient is going to die on AbioCor" and that the modest goal of the initial trials was to prolong the patients' lives to 60 days. Only if this can be achieved, he added, would the trials be expanded.
"Let's be realistic: We're talking about people who will be dead in a few days," Mehmet Oz, director of Columbia University's Cardiovascular Institute, said in April.
"This is not an issue of whether they'll be able to improve their forehand. You want them to be able to interact with their family."
John Watson, director of clinical and molecular medicine for the National Heart Lung and Blood Institute, which provided $20 million to Abiomed's research, cautioned that the trials are "a very small step" toward development of an artificial alternative to a heart transplant.
"That's way off in the future," Watson said.
Lederman said the trial implants will cost $75,000, but the company hoped eventually to reduce the price to $20,000-$25,000.
Not a final step
The AbioCor, under development for more than 20 years, was implanted by University of Louisville surgeons Laman Gray and Robert Dowling.
Its quiet, internal pump simulates the rhythm of a heartbeat and can alter its effort according to the patient's level of exertion, according to the manufacturer.
Past efforts to construct replacement hearts have had to solve two problems; clotting, which causes strokes, and infection caused by the need to run wires and tubes in and out of the patient's body.
Researchers honed AbioCor's design in bench tests and by implanting the device in calves at Houston's Texas Heart Institute.
Instead of tubes and wires, power to the AbioCor is delivered from a battery pack worn outside the body that transmits electricity through the skin to electrodes mounted in the patient's abdomen.
An internally implanted auxiliary battery is available for emergencies. The external pack has a six-to-eight hour capacity, with an additional 40 minutes available from the internal backup.
"This implantability is a major advance as far as artificial hearts go," said New York University Medical Center cardiologist Daniel Fisher.
"It's a nice development, but I don't think it's the final step."
This, said Fisher and others, is because alternative technologies have left AbioCor in a Catch-22 dilemma as far as proving its effectiveness.
Only people at death's door are eligible for implants, but if patients were in better shape, doctors would most likely use other technologies, especially implantable "ventricular-assist devices" that help a damaged heart do its own work.
"With an (assist device), if there's a problem, the patient's heart is a backup," said Patrick McCarthy, director of heart transplantation at the Cleveland Clinic, which does 30 to 50 assist-device implants a year. "There is a lot of experience with therapies to improve a person's own heart. We don't particularly like to burn our bridges."
Famed Houston heart surgeon Michael DeBakey agreed AbioCor would never be as useful as the assist device, which is "relatively simple, has less bulkiness of material, (and) requires less power."
But DeBakey credited the Abiomed team with a "very significant, very important development," because, for a small number of patients, an artificial organ is the only alternative.
Abiomed literature says the potential market for AbioCor in the United States could be as large as 100,000 patients, but this is disputed by others who say a tiny percentage of those with lingering heart disease could benefit.
Jarvik said AbioCor was so large it would only fit in people who weighed close to 200 pounds, excluding almost all women and most men: "Many years of experience have taught us that cutting out the heart is unnecessary," said Jarvik, who, like DeBakey, has invented an assist device.
"As a leader in total heart replacement, I have learned through all these years that (it) is not going to provide a public-health benefit."
Information from The Associated Press and the Los Angeles Times is included in this report.