WEDNESDAY, Aug. 25, 2004 (HealthDayNews) -- An artificial heart does an effective job of keeping heart-transplant candidates alive until -- and even after -- a donor organ becomes available, cardiologists report.
The CardioWest Total Artificial Heart substantially increased the chance that patients who needed a transplant due to heart failure would survive long enough to get that transplant. And the device more than doubled their survival rate after transplant, said a report in the Aug. 26 issue of the New England Journal of Medicine.
The report was a summary of a multicenter trial that led to a 10-1 vote in March recommending approval of the device by an advisory committee of the U.S. Food and Drug Administration, said Dr. Jack G. Copeland. He is a professor of cardiovascular surgery at the University of Arizona Health Sciences Center, and lead author of the study.
The FDA has since issued a certificate of approvability, but has not yet taken the final step needed for approval, which is inspection of the production facility of SynCardia Systems of Tucson, Ariz., maker of the device, Copeland said. That inspection is expected before the end of the month.
When approval comes, "my guess is that in time most of the large centers with end-stage transplant programs would want to add this device to their armamentarium," Copeland said.
In the trial, 64 of the 81 patients who received the artificial heart survived long enough to get a transplant, compared to 16 of the 35 patients who did not get the device. The one-year survival rate for the artificial heart patients after transplant was 70 percent, compared to 31 percent for those who got no device.
At any given time, about 4,000 heart patients in the United States are candidates for a transplant, the American Heart Association estimates, and about 2,500 transplants are done each year.
Cost could be an issue in the use of the new artificial heart, said Dr. Dale G. Renlund, a professor of medicine at the University of Utah School of Medicine, who wrote an accompanying editorial in the journal. The price of the device has been estimated at about $70,000. But hospitalization for an end-stage heart failure patient costs about that much, he said.
"The cheapest patient to care for is one who is dead," Renlund said. "The proposition that a technology that is expensive shouldn't be used in anybody because it can't be used in everybody is nonsensical."
The CardioWest device is one of several machines designed to keep an ailing heart going. It differs from the other devices because it replaces the activity of both ventricles and all the heart valves, Copeland said. The other devices replace only the left ventricle, which pumps oxygen-rich blood to the rest of the body. That makes them less effective than the CardioWest device, Copeland said.
"From the functional point of view, the total artificial heart controls blood flow and pressure completely," he said, which the left-ventricle devices do not.
One left ventricle device, still experimental, has been developed at the Cleveland Clinic. Researchers there have been given funding by the National Heart, Lung, and Blood Institute to develop a right ventricle assist device, said Dr. Kiyotaka Fukamachi, a staff scientist in the clinic's department of biomedical engineering.
Up to 40 percent of patients with end stage congestive heart failure have significant right ventricle problems that limit the usefulness of left ventricle devices, Fukamachi said. The Cleveland Clinic program could lead to human trials of a left-and-right ventricle device within five years, he said.
The cost of such devices would not be a major issue as long as they are used only as bridges to sustain transplant candidates until a donor organ becomes available, Renlund said, because the number of such patients will always be small. "It's really a niche market in an already small market," he said.
But there are signs that such limited use may someday be expanded to include tens of thousands of people with congestive heart failure who would have an artificial heart implanted permanently, Copeland said.
In Germany, 10 patients have been sent home from the hospital with total artificial hearts intended for permanent use, he said, which "opens the door to wider use of permanent implantation."
Such permanent use of the artificial heart "is a different animal, one that calls for a more difficult discussion" of cost, Renlund said.
But the permanent total artificial heart could be cost-effective if mass production reduces manufacturing cost and reduces hospital stays, Copeland said.
You can learn more about heart transplants from the National Library of Medicine.