NASHVILLE -- Country music star Randy Travis is out of surgery but remains in critical condition after suffering a stroke while at a Texas hospital, the singer's publicist said late Wednesday.

Kirt Webster, the publicist, said the 54-year-old Travis suffered the stroke Wednesday night while he was being treated for congestive heart failure because of a viral illness. Travis underwent surgery to relieve pressure on his brain. He remained in critical condition.

"His family and friends here with him at the hospital request your prayers and support," Webster said in a news release earlier in the evening.

It was not clear what kind of stroke Travis suffered. The most common type of stroke is caused by a blood clot that travels to the brain. The other kind happens when a blood vessel in the head bursts or leaks. Stroke patients who get treatment quickly are usually given a drug to dissolve the clot that caused the stroke.

The setback occurred hours after doctors said Travis was showing signs of improvement, though he remained in critical condition with congestive heart failure.

Drs. William Gray and Michael Mack of the Baylor Health Care System in Texas described Travis' condition and hospitalization in a video statement earlier Wednesday.

"His condition has stabilized, and he has shown signs of improvement," Mack said in the video. "On behalf of Mr. Travis' family, friends and associates, we would like to express our extreme gratitude for the overwhelming affection and support that Mr. Travis has received."

The Grammy Award-winning singer was in good health until three weeks before he was hospitalized, when he contracted a viral upper respiratory infection, Gray said.

The viral illness led to a weakened heart muscle that eventually worsened into heart failure.

Travis was admitted to Baylor Medical Center McKinney near his home in Tioga, about 60 miles north of Dallas, through the emergency room on Sunday. The singer underwent a procedure to have a pump inserted by catheter that helps increase blood flow before being transferred to The Heart Hospital Baylor Plano.

The North Carolina-born Travis is a traditional country purist who is a pivotal figure in the genre best known for his hits "Forever and Ever, Amen" and "Three Wooden Crosses." His Warner Bros. debut album "Storms of Life" sold 3 million copies and helped return country music to its roots.

Travis has recently been trying to put his life back together after a series of embarrassing public incidents involving alcohol. Travis pleaded guilty to driving while intoxicated in January following an arrest last year and received two years of probation and a $2,000 fine. He was required to spend at least 30 days at an alcohol treatment facility and complete 100 hours of community service.

He recently made several public appearances, including a spot on the Country Music Association Festival's nightly concert lineup and a poignant performance at George Jones' funeral.

Webster said from the hospital Travis' fiancee Mary Beougher was at his side and that he is surrounded by family and friends, including his brother, Dennis Traywick, and his pastor, Jeff Perry. Kenny Rogers, the Oak Ridge Boys, Chuck Norris and several others have called to check in on Travis.

His peers and fans have been watching Travis' progress closely, as well.

Stars like Martina McBride and Hillary Scott of Lady Antebellum and the Grand Ole Opry echoed Webster's plea for prayers to their followers.

"I always feel like he's part of our family, he's in our family," Keith Urban said in an interview Wednesday morning in Nashville. "And I was one of those guys in Australia that bought 'Storms of Life' and became a Randy fan very quickly in late '80s, and I really feel for him right now."