Houston used cocaine just before collapse in the bathtub , coroner says . Narrowed arteries `` suggest a cardiac event '' caused her collapse . CNN 's Jack Hannah and Kareen Wynter contributed to this report . Marijuana , Xanax , Flexeril and Benadryl found in her blood played no role , coroner says . Comment:
Houston used cocaine just before collapse in the bathtub , coroner says . Narrowed arteries `` suggest a cardiac event '' caused her collapse . Marijuana , Xanax , Flexeril and Benadryl found in her blood played no role , coroner says . Comment: