Huston had heart attack and drown

Official cause of death was accidental drowning
'An acute dose' of cocaine was found in the singer's system and factored into her death
Results suggest Whitney was a chronic cocaine user
Chief Coroner believes the star ingested the drug shortly before her death

Traces of marijuana, Xanax, Flexiril and Benadryl were all found but did not contribute to death

It is believed Whitney had a heart attack, fell unconscious and drowned

Heart attack may have been brought on by hardening of the arteries due to years of cocaine use

Tests did not show significant amount of alcohol in Whitney's system

Foul play and trauma did not contribute to her death
Official report expected to be released in two weeks