By David Brown
Washington Post Staff Writer
Wednesday, September 6, 2006
The Food and Drug Administration yesterday approved for use the first totally implantable artificial heart under a program that will make the complicated, $250,000 device available for as many as 4,000 people.
The decision reverses an FDA advisory panel's recommendation last year that the device was not yet ready for widespread use after many of its first 14 test patients suffered strokes. No engineering changes have been made in the heart since then, but FDA officials believe that physicians will now be able to better manage the complications that often follow its use.
The approval is the latest chapter in a half-century quest to make a mechanical replacement for the human body's most essential and hardest-working organ. It also raises anew questions about how much money should be spent briefly extending the lives of critically ill patients and how to judge the cost-benefit balance of devices that are far from perfect but better than nothing.
Whether insurance companies and the federal government's Medicare program will pay for the AbioCor (and its $100,000 implantation cost) is unknown. Medicare regulations specifically list artificial hearts as uncovered devices.
The president of Abiomed Inc., which makes the AbioCor, said yesterday that the company will seek to have that policy reversed, arguing that the device is the only alternative for many patients and that the expense compares favorably to some drug therapies for rare diseases.
The device would be limited to people with severe congestive heart failure who are estimated to have about a month to live and do not qualify for heart transplants. Those patients must also be able to take anticoagulant drugs.
Because of its size -- about two pounds -- only large women would be able to accommodate it. All the original recipients were men.
While the AbioCor's target population is relatively small, the number of Americans with less severe congestive heart failure is huge -- about 5 million. Some qualify for heart transplants but die before they can get one. Both are potential future markets for the artificial heart.
"We see this as an important milestone. It is not the beginning, and it is certainly not the end of the journey," said Daniel G. Schultz, director of the FDA's Center for Devices and Radiological Health.
The device was approved under a "humanitarian device exemption" that effectively lowers the bar for FDA approval. Normally, devices must demonstrate "safety and effectiveness," but under the exemption they need only to show "safety and probable benefit." The latter can include largely subjective measurements, such as improvement in quality of life. No more than 4,000 of the artificial hearts can be implanted under the exemption.
Unlike previous artificial hearts, the AbioCor runs with no wires or tubes piercing the skin. It is powered by a battery that is recharged with an induction coil placed against the skin. The patient can be away from an external power source for about an hour.
Of the 14 original recipients, two died on the operating table. The rest survived for an average of 5.2 months, with the longest living 17 months. Ten left the hospital only with occasional day passes. One moved to a nearby hotel, and another went home.
Despite outcomes that many experts viewed as a checkered at best, most of the patients and close family members said the time gained was valuable -- a judgment that appeared to help sway FDA officials.
"Just being able to ambulate, to clearly communicate with loved ones, and to celebrate family events is in the view of many patients and family members a significant improvement in quality of life," said Bram D. Zuckerman, director of the FDA's office of cardiovascular devices.
Before getting the device, all of the patients were essentially bed-bound. Some were breathless even while lying still. A few were attached to devices called balloon pumps that mechanically enhanced the amount of blood flowing to the body with each heartbeat.
By increasing the flow of blood and oxygen to the brain, vital organs and muscles, the artificial heart made many of the patients feel better than they had in months (at least until complications intervened, in many cases.) Michael R. Minogue, Abiomed's president, said that 11 of the 12 patients who survived surgery "reported improved interaction with their families" and eight of 12 had higher levels of activity, which ranged from getting from a bed to a chair to walking with assistance.
Six of the 12 died of strokes. More than three-quarters of the patients could not take anticoagulant drugs because of other serious conditions, and without anticoagulants, clots tend to form on implanted hardware. That can cause a stroke if the clot moves to the brain. An improvement in the design after the fifth patient reduced the risk of clotting, Minogue said.
The original patients all had a life expectancy of a month or less when the device was put in, and their net gain in longevity was 4.5 months. The "incremental cost-effectiveness ratio" of the treatment -- assuming a total cost of $350,000 -- was $940,000 per year of life gained.
"In the opinion of most health policy experts, that is not a cost-effective use of resources," said Sean D. Sullivan, director of the Pharmaceutical Outcomes Research and Policy Program at the University of Washington. "Most cancer biologics [biotech drugs] that extend life by four to five months are about one-third or one-quarter the cost of this artificial heart."
Other experts also wondered about the value of the investment.
"We are talking about a potentially very, very expensive therapy for a very common disease," said Alan M. Garber, a physician and cost-effectiveness expert at Stanford University who added that $200,000 to $400,000 "will go a long way toward vaccinating children and helping people with hypertension get better treatment -- things that are of proven benefit but cost much less."
He said, however, that there may be a benefit in bringing to market -- and paying for -- an extremely expensive device on the assumption that it would develop into a cheaper and better one.
Abiomed officials say their second-generation device, now being tested in animals, will have a target life of five years, compared with 18 months for the current AbioCor.
The first "permanent" artificial heart was implanted into Barney Clark, a 61-year-old retired dentist, in December 1982. It was powered by a 400-pound air compressor. Clark survived 112 days and suffered many complications.
Staff researcher Madonna Lebling contributed to this report.