LA Times 
Friday, March 2, 2012
It will probably take several weeks before the Los Angeles County coroner’s office determines an official cause of death for conservative website editor and author Andrew Breitbart, who died unexpectedly Thursday at age 43.
A source familiar with the investigation told The Times on Friday that although officials completed an autopsy Friday, they are awaiting results from various tests that will take six to eight weeks to be returned from the lab. The source stressed that such waits occur in most cases in the coroner’s office.
The source, who spoke on the condition of anonymity because the case was still under investigation, said officials are working on the assumption that Breitbart died of natural causes. A witness saw him collapse while walking near his home and said that he had no external injuries, the source said. Paramedics rushed Breitbart to Ronald Reagan UCLA Medical Center, where doctors pronounced him dead.
“It looks like a heart attack, but no one knows until” an autopsy is done, Breitbart’s father-in-law, actor Orson Bean, told The Times.
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