A controversial operation that folds the scarred portion of a damaged heart in on itself to get it to beat more effectively offers no real benefit to most patients, researchers reported on Sunday.

The operation, known as ventricular reconstruction, is designed to help people with heart failure, a condition that affects about 5 million in the United States alone and often occurs after tissue is damaged by a heart attack.

Generally, the heart tries to compensate for the damage by getting larger, but it also pumps far less efficiently.

Doctors in a trial called STICH compared what happened to 1,000 volunteers, who all got heart bypass operations. Half also got ventricular reconstruction.

Ventricular reconstruction did nothing to reduce the death rate or the risk of going back to the hospital. It also did nothing to improve the quality of life after four years, the researchers told a meeting of the American College of Cardiology in Orlando.

"It doesn't seem to have any great benefit at all," Dr. Robert Jones of Duke University Medical Center in North Carolina said in a telephone interview. With the surgery, "many patients have a lot fewer symptoms, but some people improve that much with good medical treatment" that includes drugs.

By not doing the reconstruction, the researchers said, it will save an average of $14,595 in hospital costs per patient, and patients will spend one half hour less in the operating room.

"The cost difference is substantial," said Jones.

Dr. Robert Michler of the Montefiore-Einstein Heart Center in New York City said in a telephone interview that the operation is seldom done in the United States anyway, and estimated that 3,000 to 5,000 such procedures have been done worldwide in the last 10 years.

"This started in South America, it was really popular in Europe, and there are a lot of evangelists for this operation," said Jones. But others have seen in practice that it adds little benefit, he said. "I think those guys have figured out on their own that it's not a whole lot better. A lot of surgeons have been waiting for the results of this trial."

The findings, based on work at 96 medical centers in 23 countries, were also published in The New England Journal of Medicine.

"On the basis of this trial, the routine use of surgical ventricular reconstruction in addition to CABG (bypass surgery) cannot be justified," Dr. Howard Eisen of Drexel University College of Medicine in Philadelphia said in a commentary.

Michler said further studies will show whether there are still some patients who might benefit from the operation, which reduces the size of an enlarged heart by 20 percent.

"That's three times what you can get with medicine alone," he said. "The hope was if you could acutely and dramatically change the size of the heart, you may be able to benefit people."

Eisen said it is now apparent that surgically reducing the size of the heart is different from shrinking it with conventional heart failure therapies.