Murray P. Haydon today became the world's third recipient of a permanent artificial heart in a speedy, 3 1/2-hour morning operation that proved remarkably routine despite its highly experimental nature.

"We ought to start charging for this procedure, we're starting to get so good at it," said Dr. William C. DeVries, who implanted the mechanical heart, as Haydon was being wheeled out of surgery just before noon. DeVries also implanted artificial hearts in the two pioneering patients who preceded Haydon.

At an afternoon news briefing, Dr. Allan M. Lansing, head of the Humana Heart Institute International, called today's implant "a very successful morning with no complications, a very smooth procedure and, up to now, an excellent postoperative course."

Dr. Jerome Lacy, Haydon's personal cardiologist, said in a telephone interview this evening that he had visited Haydon and found him "alert and oriented. He opened his eyes and blinked at me. I'd ask him a question and he'd shake his head. He looks perfect." At a 9 p.m. update, Humana reported that Haydon was "awake and moving all his limbs . . . . All vital signs are stable."

Haydon's wife of 32 years, Juanita, visited him twice after the surgery. He squeezed her hand after coming out of anesthesia just after 5:30 p.m., a spokesman said.

Despite the operation's initial success, however, it is too early to tell whether Haydon, a retired auto worker from Louisville, will suffer complications similar to those that plagued the first two artificial-heart recipients, Barney B. Clark and William J. Schroeder.

Humana officials and Haydon are hopeful, however, that, because he was healthier at the time of surgery, he will fare better with the experimental device, which is identical to the Jarvik-7 device implanted in Schroeder.

"We think it will be a more accurate test of the heart itself," Lansing said today.

Haydon's new lease on life began today with an early-morning ride into the operating room. A chest incision was made at 7:47 a.m., Lansing said, and 25 minutes later he was attached to a heart-lung bypass machine that kept him alive during the surgery.

With clockwork precision, the team headed by DeVries removed the two lower chambers, or ventricles, of Haydon's heart and began the "very meticulous" process of sewing and snapping in the aluminum-and-plastic parts of his new pump.

The left artificial heart chamber was started up shortly before 10 a.m., and the right chamber 10 minutes later. Haydon was then taken off the bypass, and by 11:15 a.m. his chest was closed.

As in his earlier operations, DeVries had an eclectic selection of his favorite music during his work, including a Vivaldi mandolin concerto and Elizabethan lute music.

DeVries, who implanted the first man-made heart in Clark at the University of Utah in December 1982, was lured to Louisville after Humana Inc., one of the country's largest for-profit hospital chains, pledged to finance up to 100 implants here.

Schroeder became the second mechanical-heart recipient last November in an operation in the same surgical suite at Humana Hospital-Audubon used in today's operation. He was in surgery nearly twice as long as Haydon, in part because of scar tissue from an earlier coronary bypass operation.

Schroeder, 53, remains at the hospital after suffering a stroke in mid-December that left him with speech and memory problems. For the past two weeks he has been bedridden with a flu-like condition that his doctors attribute to a reaction to an antiseizure medication.

After today's operation was completed, Schroeder's wife, Margaret, visited Juanita Haydon. Lansing said later that Schroeder, informed this morning by a hospital staff member of the new heart implant, replied simply, "That's good."

Clark underwent a roller-coaster recovery for 112 days before his death in 1983.

Schroeder and Clark had more advanced heart disease before surgery than did Haydon, along with other complications. Although Haydon's health was declining rapidly -- he lost 25 pounds over the past month -- he was expected to live another two or three weeks if nothing were done.

Clark, then 61, was near death when he was rushed into surgery and might have died within hours without the implant. His lungs had been weakened by years of smoking and other organs were damaged by the severity of his heart disease, a deterioration of the heart muscle called cardiomyopathy.

His seizures were later attributed to the mechanical heart, perhaps because doctors turned up its powerful drive system and pumped blood into his debilitated body more rapidly than he could handle.

Schroeder, who was thought to be healthier than Clark at the time of his surgery, had undergone coronary bypass surgery in an unsuccessful attempt to control the coronary artery disease that affected his heart, as well as gall bladder surgery. He also, as a diabetic, is more susceptible to infection.

Though the mechanical heart is strongly suspected as the cause of his stroke, his clogged arteries also increased the risk of an embolism cutting off blood to the brain.

Haydon's heart problem, like Clark's, resulted from heart muscle deterioration. Because he shows no evidence of unusual hardening of the arteries, he is less predisposed to a stroke than is Schroeder, physicians said.

Although Haydon had smoked for 40 years before quitting four years ago, Lansing said there was no evidence that the practice had seriously damaged his lung function.

"We're down to just what is the effect of the heart itself," said Lansing, putting increased focus on how well Haydon does as a measure of the success of the program.

Lansing said today that, should another major neurological or brain complication afflict Haydon, it would give "us great cause for concern. . . . Hopefully, it wouldn't stop the series completely."

DeVries has federal permission to do four more implants. Like the first three patients, future candidates must have exhausted conventional treatments before turning to the experimental surgical device.

Dr. Robert Jarvik, inventor of the mechanical heart implanted in the first three patients and president of Symbion Inc., the company that manufactures it, took a more long-range view of the experimental investigation. He emphasized that it would take "many patients" to "properly investigate" the device, regardless of Haydon's outcome.

The potential value of the artificial heart, in terms of its expense and the quality of life it offers patients, is being debated widely in the medical community.

Although the treatment for Haydon is similar to that for Schroeder, Lansing said extra precautions are being taken against clots that might cause a stroke. He is being given drugs to thin his blood.