A top aide to accused swindler Allen Stanford entered the first guilty plea on Thursday in a $7 billion fraud case as Stanford was hospitalized with an extremely high heart rate.

James Davis, 60, pleaded guilty to three felony counts as part of a plea deal with federal investigators. Davis was the former chief financial officer of Stanford International Bank, which is accused of swindling investors out of $7 billion through a Ponzi scheme involving certificates of deposit issued by Stanford's Antigua bank.

Stanford, Davis' long-time friend and former college roommate at Baylor University in Waco, Texas, missed a court appearance to decide his legal representation because he was hospitalized.

At 5:30 a.m. CDT Mr. Stanford was found to have an irregular electrocardiogram and an extremely high pulse rate, Judge David Hittner said at a hearing. He was taken to Conroe Regional Medical Facility.

Stanford, who was in a Conroe, Texas, jail awaiting trail after being indicted on 21 felony counts, said in media interviews before his June 18 arrest that Davis was responsible for the fraud.

Davis apologized for his actions outside the courthouse after the hearing.

I did wrong. I'm sorry, Davis said, wearing a dark suit. I apologize. I take responsibility for my actions.

He faces a maximum of 30 years in prison on the conspiracy, fraud and obstruction charges, and will be sentenced on November 20.

Davis has been free on $500,000 bail since his initial court appearance in July when he pleaded not guilty to a three-count criminal information.

Stanford implied in media interviews before his arrest that Davis was responsible for the fraud.

Stanford and four other executives are charged with falsifying accounting documents and bribing a regulator in Antigua to keep the alleged CD Ponzi scheme hidden.

(Editing by Gerald E. McCormick and Steve Orlofsky)