The man who received the world's first self-contained artificial heart had been in "dire" condition, suffering from kidney failure and diabetes, in addition to having had several heart attacks, his doctor said Wednesday.

Officials of Jewish Hospital declined to release the patient's name or his hometown but said he was in his mid- to late 50s.

Because of his poor condition — he had been given an 80 percent chance of dying within 30 days — he had been turned down for a heart transplant elsewhere, doctors said.

"He had no other option," Dr. Laman Gray told reporters. "He was in as dire shape as you can ever have anybody in."

The man has chronic kidney failure, diabetes and had multiple heart attacks, Gray said. He had had previous coronary bypass surgery, around 1992.

Doctors said they expect the artificial heart to extend the patient's life by only about a month.

The softball-sized titanium and plastic pump was implanted Monday by Gray and colleagues from the University of Louisville during a seven-hour operation at Jewish Hospital.

The hospital said the patient was resting comfortably and had been responsive to family members Tuesday night but did not speak.

It was the first major advance in the development of an artificial replacement heart in nearly two decades, although it received a cool reception from one of the field's best-known pioneers, Dr. Robert K. Jarvik.

"Many years of experience have taught us that cutting out the heart is unnecessary," said Jarvik, who helped develop artificial heart technology. Medical science should instead focus on devices that assist the heart in healing, he said Tuesday.

Jarvik said the new device is too large to fit almost all women and would affect only about 1 percent of the potential heart transplant candidates.

The device, called AbioCor, has electronic controls that adjust the pumping speed based on the body's needs. It is powered by a small battery pack worn outside the body that transmits current through the skin.

The heart also has a rechargeable internal battery, about the size of a pager, that can work on its own for about 30 minutes — long enough for a patient to remove the battery pack and take a shower, for example.

"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 yet a reality: "This is obviously an experimental device whose long-term success has to be demonstrated."

Abiomed Inc., the Danvers, Mass.-based maker of the device, sees it as a potential tool to not only save lives but to allow patients to maintain a quality of life after heart failure.

Over 700,000 Americans die each year from heart failure and this new technology could benefit more than 100,000 people in the United States, the company said. 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 AbioCor is considered a technological leap from the mechanical hearts used in the 1980s. Those devices 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. Five people would get the device in the early 1980s.

The first recipient, Barney Clark, a Seattle-area dentist, lived 112 days after receiving a Jarvik-7 in 1982. His widow was pleased Tuesday upon hearing there had been a completely contained, mechanical heart implanted in Kentucky.

"I'm really thrilled," said UnaLoy Clark-Farrer from her home in St. George, Utah, recalling her late husband's decision to volunteer his life for medical science.

Some doctors, including Robert Higgins, chairman of cardiology at the Medical College of Virginia in Richmond, said artificial hearts are unlikely to replace donor hearts.

"A donor heart in a good transplant can last 15 to 30 years," he said. "It's going to be hard to replace that with a machine."

The latest experimental heart was implanted by Gray and Dr. Robert Dowling, one of only a few surgical teams across the country trained to use the device in human experiments.

The hope is that such mechanisms will one day allow recipients to lead a relatively normal life, said John Watson of the National Heart Lung and Blood Institute, which has given $20 million toward research into self-contained artificial hearts.