Doctors are reporting surprising early success with a novel treatment they hope will one day cure congestive heart failure in thousands of dying patients: They shrink the bloated heart with drugs while an artificial pump temporarily takes over the workload.

Though small, the British study more than tripled the usual recovery rate for patients with severe heart failure, a common killer once viewed as unstoppable. Eight of 24 patients seem fully recovered, though their dying hearts had once ballooned up to twice the normal size. And the benefit has lasted at least four years and counting.

"Maybe, in some patients, the failing heart is not end-stage after all," Drs. Dale Renlund and Abdallah Kfoury of the Utah Transplantation Affiliated Hospitals declared in an accompanying editorial.

The findings were published in Thursday's New England Journal of Medicine.

The technique must now be confirmed in larger studies and probably will not spread anytime soon in the United States, since one of the drugs isn't even approved for general use here, doctors say. Also, heart pumps can cost $200,000, including hospital care. The study was backed by pump maker Thoratec Corp. of Pleasanton, Calif.

Nevertheless, the findings excited doctors, because congestive heart failure afflicts about 5 million Americans and each year kills about 58,000. Some drugs and pacemakers treat its early forms, but it often gets worse. These damaged or overworked hearts ultimately pump so weakly that sufferers cannot even perform simple daily tasks.

Once that happens, the only solution is either a transplant — and donor hearts are scarce — or an artificial heart pump. These implanted pumps can take over much of the heart's work, but they can cause clots or infections in the long run and bring about recovery in no more than 10 percent of patients. Something else is needed.

The English team at Harefield Hospital in Middlesex got the idea of combining the heart drugs and the implanted pumps. The theory was that the devices would give the heart a working vacation while the drugs returned it to its normal size.

Since this rest can eventually weaken heart muscle, the researchers added one more drug, a heart-strengthener called clenbuterol.

As the study began, the hospital put the pumping implants into 24 patients without a previous heart attack or infection. Nine were too sick for further treatment or soon died, but 15 took all the drugs. Eleven were well enough to remove the implants mostly within a year, and the treatment left eight fully recovered.

Four years later, they were leading "normal lives, with normal heart function," said lead researcher Emma Birks. "It's quite dramatic, really."

Dr. Gregg Fonarow, a heart failure expert at UCLA, said up to 40,000 Americans might ultimately be candidates for such treatments each year, if the technique is clearly proved by bigger and better studies. "This could be incredibly important," he said.

Others also wondered whether patients with earlier disease could take a similar battery of drugs, get better, and maybe never need the heart pumps.

Yet some were doubtful about the study's approach and small size. Dr. Steven Nissen, a Cleveland Clinic heart expert, said it is impossible to tell without a comparison group how such patients would fare without a heart pump or some of the drugs.

"It's a very interesting paper," he said. "I have some concerns about whether it's actually going to represent the breakthrough that it seems."

The heart-strengthening drug, clenbuterol, is sometimes used to bulk up cattle or athletes but is not approved by the FDA. It is not clear if it would work well or safely in many patients, doctors say.

Dr. Eric Rose, a pioneering heart-pump surgeon at Columbia University in New York, questioned how the other drugs — which are often used for heart disease — could seemingly work so well in these patients, when coupled with the implants.

"This field has been plagued by hyped expectations in the past," he said. "It can have the effect of setting the field back. I hope that won't be the case here."