Rik Mayall's wife says the comedian suffered an "acute cardiac event," though a coroner's office says a post-mortem on the late entertainer was inconclusive.
Mayall, a pioneer of British alternative comedy and star of the sitcom "The Young Ones," died suddenly on Monday. He was 56.
Barbara Mayall said Thursday that the comic collapsed as he returned from a run.
West London Coroner's Court said more tests would be conducted.
Police said they were called to Mayall's house by London Ambulance Service, where the performer was pronounced dead. Police officers said the death was not believed to be suspicious.
In the 1980s Mayall was part of the Comic Strip, an influential group of alternative young comics that included Dawn French, Jennifer Saunders and Adrian Edmondson.
Mayall memorably played Conservative politician Alan B'stard in the sitcom "The New Statesman." He and Edmondson also created and starred in slapstick comedy series "Bottom" and starred in the 1991 film "Drop Dead Fred."
In 1998 he was seriously injured in all-terrain vehicle accident that left him in a coma for several days.