DOCTORS CALL YELTSIN BYPASS A SUCCESS.

Byline: Lawrence K. Altman The New York Times

President Boris N. Yeltsin came out of a seven-hour, multiple-bypass heart operation in a Moscow hospital Tuesday with his doctors declaring the operation a success. They said they were optimistic about the 65-year-old Russian leader's chances of resuming a full workload.

At a news conference in the hospital an hour after the operation, the doctors said the surgery went without a hitch. Yeltsin's heart was stopped for 68 minutes at one phase of the operation.

During the procedure, surgeons sewed five grafts to restore blood flow to coronary arteries. They had become constricted by the fatty deposits of atherosclerosis that had built up over a period of years and deprived the organ of vital nourishment, leading to two heart attacks.

Even if all goes well for Yeltsin, it may yet be months before he can run the country again.

Yeltsin was reported in stable condition Tuesday in an intensive care unit, where he remained connected to an artificial respirator used during the operation. He opened his eyes early Tuesday evening but had not fully awakened from the anesthesia. Patients usually awaken from six to 18 hours after such surgery.

Yeltsin still faces certain potential risks like bleeding, infection and kidney failure as he enters a critical phase over the next several days. Other possible complications after such surgery include neurological damage, like a stroke, or memory loss that may not become apparent until later.

But Dr. Michael DeBakey, the American heart surgery pioneer who consulted in Yeltsin's case and observed the operation, called it ``a complete success.''

``President Yeltsin will be able to return to his office and carry out his duties in normal fashion,'' said DeBakey, 88, who works at Baylor College of Medicine in Houston.

Dr. Renat S. Akchurin, 50, the surgeon who headed the team, said Yeltsin's heart muscle was now getting enough blood to function normally. But Akchurin said it would be several days before Yeltsin is able to sign a decree resuming the presidential responsibilities that he turned over to Prime Minister Viktor Chernomyrdin minutes before undergoing anesthesia at 7 a.m.

Yeltsin will decide himself when he will reassert his authority, Akchurin said. The doctor's face and voice reflected exhaustion from performing the operation.

With the advent of managed care in the United States, many patients now leave the hospital four or five days after undergoing bypass operations. But hospital stays in Russia are generally much longer. And experience suggests that a few months will pass before Yeltsin feels fully recovered from the surgery.

Nevertheless, the favorable comments from the surgeons are likely to ease tension about Yeltsin's health just as DeBakey's comments did at a news conference in Moscow six weeks ago after he examined Yeltsin.

At that time, DeBakey said that Yeltsin had a condition known as a ``stunned myocardium'' and that it would take six to 10 weeks for Yeltsin's heart to improve function and for several other medical problems to clear up before he could undergo the bypass operation with minimum risk.

Ever since Yeltsin announced Sept. 5 that he needed heart surgery, the Kremlin had been combating rumors that Yeltsin could never serve out his term, which ends in 2000. That created an enormous power struggle in the Kremlin.

A number of doctors not connected with Yeltsin's case criticized DeBakey for delaying the surgery. But DeBakey said their criticisms were unfounded, in part because they did not know the case. Yeltsin's aides contributed to the problem by saying he had liver and kidney failure. But tests showed that he did not have those conditions, DeBakey said in September.

DeBakey said in an interview Tuesday that ``everything went beautifully.'' The apparent success of Yeltsin's operation ``vindicated my position a little over a month ago when there was doom and gloom all over the place,'' DeBakey said.

As further evidence, DeBakey said that a measure of heart function known as the ejection fraction rose to 40 percent just before surgery from 20 percent in September. The ejection fraction is the amount of blood the heart expels with each beat - usually about 65 percent of the blood in the heart's main chamber.

CAPTION(S):

PHOTO Dr. Renat Akchurin describes the seven-hour surgery Tuesday in which the Russian leader's heart was stopped for 68 minutes.

Associated Press