US actress Anne Heche is in a coma and has not regained consciousness following a collision that left her vehicle “engulfed in flames”, a representative has confirmed.The 53 year old, who dated chat show host Ellen DeGeneres between 1997 and 2000, was taken to hospital following the incident on the morning of Friday 5 August in the Mar Vista area of Los Angeles and remains in a critical condition. Anne rose to fame after starring in the US soap Another World, and is best known for films including Donnie Brasco, Cedar Rapids and the 1998 Psycho remake.