TMZ: Playboy founder Hugh Hefner died of cardiac arrest

CALIFORNIA -- Playboy founder Hugh Hefner's cause of death has been revealed. TMZ reports Hefner ultimately died of cardiac arrest, but his death certificate reveals he was also battling other illnesses.

According to the document, Hefner was suffering from septicemia -- which is a severe inflammation of body tissues triggered by an infection in the blood. TMZ reports Hefner had also been dealing with E. coli -- and both are listed as contributing factors.

Hefner passed away on Wednesday, September 27th at the age of 91. He was laid to rest at a private ceremony in Los Angeles on Saturday, September 30th.