LOUISVILLE, Ky. (AP) - Jim Pray has waited more than nine months in a hospital room for a heart transplant.

He's not holding out hope that a groundbreaking experiment - the first implantation of a self-contained artificial heart - will come to his rescue. Still, he's optimistic for the future.

"You get excited when there's any advancement. Even if it doesn't help you, it may help someone else," Pray said from his room at Temple University Hospital in Philadelphia.

On Monday, Drs. Laman Gray Jr. and Robert Dowling placed the wireless, tubeless artificial heart in a terminally ill man as part of an experiment to test the effectiveness of the device.

The man, described as a diabetic in his mid- to late- 50s with liver and kidney failure and a history of heart attacks, was on a ventilator and resting comfortably on Saturday, said Jewish Hospital spokeswoman Linda McGinity Jackson.

His condition has been stable all week and doctors remain guardedly optimistic the experimental device will sustain him for at least 60 days - a goal set by AbioMed Inc., the Danvers, Mass., company that manufactured the device. Gray and Dowling, the University of Louisville surgeons, said they hope the man will one day leave the hospital.

But experts said it will take years before the device becomes widely available - and only if it proves itself in long-term use among several dozen experimental patients.

Dr. Robert Higgins, chairman of cardiac surgery at the Medical College of Virginia, doubts the AbioCor artificial heart will ever be used for all those in need of a heart transplant.

But together with other devices to aid the heart in functioning, it could be an effective tool in fighting heart failure, which is responsible for more than 46,000 deaths annually. Nearly 600 people who were on waiting lists for donor hearts died last year.

"We just have not been able to fill the void between the number of people that need heart replacement therapy and the number of donor organs available," Higgins said.

The Food and Drug Administration has given approval for five experimental surgeries to be performed. Hospitals in Los Angeles, Philadelphia, Louisville, Boston and Houston are prepared to do them.

Candidates for the experimental surgery must be over 18, have an 80 percent chance of dying within 30 days and be ineligible for a human heart transplant.

Though the first recipients must be gravely ill, future patients are expected to be able to engage in normal activities, even perhaps light sports such as golf.

Twice in the last 10 days, Pray has ridden the emotional highs and lows of first learning that he may finally receive a heart transplant, then hearing it won't happen.

"You are always afraid that there will be some complications that will postpone it," said Michael Spight, 52, of Detroit. Spight has waited three weeks for a heart.

He uses a left ventricle assist device to aid in pumping blood while he waits for word on his transplant at the Cleveland Clinic.

There were more than 4,200 people awaiting heart transplants in the U.S. as of June, and about 2,200 heart transplants were performed last year, according to the United Network for Organ Sharing.

It's expected that an average of 7,500 will be put on the list during a year. For many it's a terrifying wait, Higgins said.

"Their lives are consumed by that waiting, that unknowing," he said.

Pray, 53, learned 10 years ago he had congenital heart failure. Without a new heart, his own will eventually lose the strength to beat and he will die.

He is on a ward with about 35 other patients awaiting transplants.

"I'm anxious to see how this heart works," he said.

Copyright 2001 The Associated Press. All rights reserved.