"They are looking at the heart," agent Richard Howell told ESPN.com. "They preliminarily see an abnormality, but they still have a lot of work to do. It could be anything, and they're looking at everything."
Howell said he had received no further specifics on what particular type of heart abnormality Collier apparently had. Collier died early Saturday after experiencing trouble breathing at his home. His wife administered CPR, but Collier was pronounced dead on arrival at a suburban Atlanta hospital.
Forsyth County coroner Lauren McDonald said it could take up to six weeks before the autopsy is finalized. Pathologists and technicians are conducting numerous tests and reviewing Collier's medical records from his time with the Houston Rockets and Hawks as part of their investigation.
Hawks spokesman Arthur Triche said the team had been asked by Collier's family to defer any comment until after Collier's funeral Wednesday.
Howell stressed that the Collier's apparent heart abnormality was only one of many causes of death being investigated by the coroner's office. He said he was concerned over what he perceived as a growing public misperception that an exact cause of death had already been determined and was being kept from the public.
"The real story here is what a tragedy this is for Jason's family," Howell said. "The autopsy is incomplete, period, and there is no autopsy report being withheld. The facts are that the family is anxiously awaiting the autopsy and have not made any specific request that the autopsy results not be released."
McDonald said he regretted if his earlier comments regarding the family's wishes had been misconstrued.
"I want people to focus on his life, not his death," McDonald said.
Heart ailments among basketball players have been a major topic in the NBA for the past month. Center Eddy Curry, who missed the final 13 regular-season games and the playoffs last season after experiencing an irregular heartbeat, was traded by the Chicago Bulls to New York earlier this month after he refused to take a DNA test that might have shown whether he was genetically susceptible to cardiomyopathy.
Reggie Lewis of the Boston Celtics died of sudden cardiac arrest in 1993, and Loyola Marymount forward Hank Gathers collapsed during a game and died on the court in 1990. Both were afflicted with hypertrophic cardiomyopathy, an excessive thickening of the heart muscle.
During his three seasons with the Rockets, Collier spoke often of the lake home he hoped to build someday in Georgia, where he had met his wife, Katie, and played at Georgia Tech. Collier wound up with the Hawks in March 2004 and was in the process of building a home on Lake Lanier, about an hour away from his job with the Hawks.
"He was a really nice kid, really fun to be around, and that's what makes it even more difficult," said Detroit coach Flip Saunders, who worked with Collier with the Minnesota Timberwolves in October 2003.