The senior statesman underwent open-heart surgery in a Virginia hospital Thursday.
Helms aide Jimmy Broughton says the 80-year-old senator remainsin a hospital cardiac intensive care unit but received visits fromwife Dorothy and others in his family.
Doctors replaced the pig valve Helms had inserted 10 years ago with a tissue value, in a procedure called Redo Mitral Valve Replacement. They also repaired another valve in a procedure called Tricuspid Annuloplasty.
"He did very well and is stable in the postoperative Cardiac Intensive Care Unit. All vital signs are stable," said Jimmy Broughton, Chief of Staff to Helms.
The surgery took five hours. The surgical team, led by Dr. Alan Speir, says things went well, and they are pleased with the procedure.
But friends and associates of Helms were cautious Thursday when asked about his recovery schedule.
"All in all, it went really well,'' said Dr. Bert Coffer, a Raleigh physician and longtime friend of Helms' who spoke with one of the surgeons. "Of course, this is just the first hurdle."
"The next 48 hours are very important,'' said Broughton.
Possible risks in coming days include a stroke, pneumonia or additional heart failure.
Doctors hope to gradually remove Helms from an artificial breathing device as he wakes up this morning, Coffer said.
Helms went into pre-op at Inova Fairfax Hospital in Fairfax, Va., around 7 a.m. His family spent an hour with him before that. His three children, four grandchildren, and wife Dot are all with him in Virginia.
The 80-year-old Republican is expected to remain in intensive care for three to five days. He could be in the hospital 10 days to two weeks.
Broughton said it is hard to predict when he will resume a full schedule.
Helms announced last August that he plans to retire next January after 30 years in the Senate. He said he wanted to spend more time with his family during his twilight years.
He was admitted to the National Naval Medical Center in Bethesda, Md., earlier this week after complaining of feeling weak.
The valve from the heart of a pig was used to replace Helms' mitral valve in 1992. The mitral valve guards the opening between the left upper and lower chambers of the heart.
It is not unusual for the pig valves to wear out and need replacement after a period of years. Doctors continue to use them because, unlike mechanical valves, they don't promote the formation of blood clots.
Helms has had a variety of ailments in recent years.
He had knee-replacement surgery in 1998 and was diagnosed with "peripheral neuropathy," a condition that numbs his feet and impairs his balance, in 2000.
That same year, he was hospitalized with a serious case of pneumonia, and last year he had fluid drained from his lungs after contracting what aides described as "a bad head cold."
Helms is known for his strong opposition of communist regimes and his criticism of foreign aid. He used the chairmanship of the Senate Foreign Relations Committee, which he held from 1995 to 2001, to promote his views.