Artificial Heart’s Inventor Unable to Finance Testing
The dentist who designed an experimental artificial heart that was implanted in a human without federal approval says he has improved his air-driven Phoenix Heart but needs money for further development and testing.
Kevin Cheng believes that his latest versions are superior to anything else in use.
But he is unable to finance costly animal testing to prove that his devices work, which could bring federal approval for experimental use in humans, or to develop a fully implantable and internally driven heart.
Cheng said he needs at least $300,000 for animal testing and may have to try to find foreign backers for testing overseas, perhaps in Japan or Taiwan.
Last Best Hope
Cheng, who has sought federal and private grants without success, says his last best hope for testing in the United States rests with the University of Arizona in Tucson. But while he has supporters there, federal support is unlikely for another air-driven heart pump because it involves old technology.
Such devices, including current Jarvik hearts, are powered by external machines that pump air through tubes that pass through the patient’s chest wall. The patient is tethered and susceptible to infections because of the tubes.
Cheng, 46, achieved notoriety in March, 1985, when an earlier Phoenix Heart intended for calf testing was used at University Medical Center, which is affiliated with the Tucson school, in an emergency without authorization by the federal Food and Drug Administration.
The Phoenix Heart kept alive a patient, whose body had rejected a donor heart, for 11 hours before a second transplant. The man died of complications unrelated to the device.
Dr. Jack G. Copeland, the medical center surgeon who arranged for its use, afterward acquired FDA-approved Jarvik-7 devices and pioneered their use as bridges to keep patients alive until transplants were available. Jarvik hearts, which were permanently implanted in five recipients in the United States and Sweden, have since been used as transplant bridges about 150 times in the United States.
Between 1983 and 1987, Cheng implanted his devices in 10 calves for as long as 10 days, but expenses forced an end to the experiments. Each polyurethane heart costs $15,000.
In the meantime, Cheng is at a standstill with virtually no testing accomplished on his new designs, elliptical, polyurethane Phoenix-7 and Phoenix-8 models.
Design Superior, He Says
He insists that his design is superior to the Jarvik heart, with greater blood volume per stroke and slightly smaller size.
The Phoenix heart’s three pumping membranes, versus the Jarvik’s one, will effectively remove all blood from the ventricle, “and no one else has done that yet,” said Dr. Willem J. Kolff, one of the nation’s most respected researchers on artificial hearts.
Kolff developed the first successful kidney dialysis machine and is chief of the University of Utah’s Division of Artificial Organs, where the Jarvik heart was developed.
Cheng’s heart “is novel, it’s promising, it’s unusual,” Kolff said. “I see no reason why it should not work. It should be tested.”
If the Phoenix Heart was available and fully tested today, “I’d say we could put it in instead of the Jarvik” in bridge situations, said Richard Smith, chief biomedical engineer at University Medical Center. But he said he thought it would be more useful for Cheng to work toward a permanent, totally implantable heart with an internal motor.
Ultimate Goal
Cheng’s ultimate goal is a completely implantable electro-hydraulic artificial heart, using currently available technology, to provide patient mobility and a quality of life lacking when the patient is tethered to an air-driven pump.
Cheng, who worked at the Texas Heart Institute while in dental school, said he wants to complete his 12-year-old project, which has cost him $200,000, “to save some human life.”
