Garry Shandling was experiencing shortness of breath and pain in his legs just one day before his death, PEOPLE has learned.
Assistant Chief Coroner Ed Winter told PEOPLE that Shandling, 66, spoke to a doctor friend before his death, complaining about the discomfort in his legs and shortness of breath.
“[His friend] stopped by that night, and Garry didn’t want any medical attention,” said Winter.
According to Winter, when Shandling still wasn’t feeling well the next day, he told his friend he was going to go to the hospital. “Garry said he would get checked out, and he collapsed 45 minutes later,” said Winter.
PEOPLE previously confirmed that Shandling collapsed while on the phone with 911 before being taken to St. Johns hospital in Santa Monica, California, where he died Thursday.
While it’s been reported that the comedian suffered a heart attack, Winter said the investigation remains open, and that Shandling does not yet have a death certificate.
“There’s no doctor to sign the death certificate and we are looking into it,” explained Winter.