Gaines Adams, a defensive end with the Chicago Bears, died Sunday after he was taken to a Greenwood, S.C., emergency room, the county coroner told ESPN.
Greenwood County Coroner James T. Coursey said Adams was taken to the regional hospital, where he was pronounced dead at Sunday morning.
Coursey said the preliminary autopsy indicated Adams died of cardiac arrest caused by an enlarged heart.
Adams, 26, listed at 6-foot-5 and 256 pounds, played in college at Clemson and was drafted by the Tampa Bay Buccaneers with the No. 4 overall pick in the 2007 NFL draft. He was traded to the Bears in October.
"I remember him at the 2007 draft as a fine young man," NFL commissioner Roger Goodell said. "Our condolences to Gaines' family, his teammates on the Bears and Buccaneers, and their organizations on their loss."