Her health was frail, her career failing: the final days of Brittany Murphy

Concerns about the Hollywood actress's physical and mental state had been growing before her death

As friends and relatives yesterday mourned the death of Hollywood actress Brittany Murphy, fragments emerged about the last weeks of her life, marred by personal and professional humiliations which included her abrupt exit two weeks ago from a film set in Puerto Rico, as well as frail health.

Preparations began yesterday at the Los Angeles coroner's office for an autopsy on Ms Murphy, who was found by emergency medical personnel in full cardiac arrest on Sunday morning at the home she shared with her mother, Sharon, and her British screenwriter husband Simon Monjack, in the hills above the Sunset Strip. She was declared dead upon arrival at the Cedars-Sinai Medical Centre.

Officials moved quickly to dampen speculation about her death. "It appears to be natural," Ed Winter, the chief coroner said on Sunday evening. It could be weeks before definitive results from a toxicology report are available. They could reveal other contributing factors to the heart attack. The Los Angeles Times reported that a large quantity of prescription medications was found in the home.

Ms Murphy, whose breakthrough as a teen actress came with her role in the 1995 film Clueless and who went on to take co-starring parts in both 8 Mile, alongside the Detroit rapper Eminem, and Girl Interrupted with Angelina Jolie, had recently surprised fans at a fashion outlet opening in Los Angeles with looks that were even more gaunt than usual.

"I am a bit thinner now than what I would like to be," Ms Murphy told a reporter at the opening on 3 December. However, she said her new year's resolutions for 2010 would include having a child. "But that's kind of a large one," she conceded.

Over the years, Ms Murphy has been forced to deny rumours both about illegal drug use and serious eating disorders. As for the former, she told the now-defunct Jane magazine in 2005, that reports of her using cocaine were "pretty darned far-fetched". She added: "I am also way too high-strung. I can't even take a Sudafed. Can you imagine? My God. I think my heart would explode. I mean, literally."

The Hollywood writer Michael Adams recalled that in a 2002 interview, Ms Murphy told him that she had a serious heart condition. He said he asked the same question about drug abuse. "She laughed and said even if she wanted to she couldn't take (illegal substances) because she'd had a heart condition since she was a little girl."

Sources said that a "significant amount of vomit" was in the bathroom when the paramedics got to her home, responding to an emergency phone call placed by Mr Monjack, who said his wife was unwell.

That all was not perfect at least in the professional world of Ms Murphy was reflected in an unflattering sketch in a recent episode of the comedy show Saturday Night Live, in which the actress was portrayed mistakenly thinking she was a host on the show when she wasn't. The sketch, which portrayed the actress as severely disorientated, was apparently prompted by reports of her being sacked from the set of The Caller, a film now in production in Puerto Rico. The sketch has since been taken down from the show's website.

Rumours also surfaced of trouble on the set of another film that featured a performance by Ms Murphy. Hollywood blog sites reported that she had seemed only half-conscious while shooting some scenes in Something Wicked, an independent film recently in production in Oregon. "Her husband was her handler, he shuttled her around. She was barely there," someone who claimed to have knowledge of the circumstances on the set told The Wrap, a celebrity news website. "She'd go in and out of consciousness in the middle of takes."

Nicole Perna, the actress's publicist, said in a statement on Sunday night, "In this time of sadness, the family thanks everyone for their love and support. It is their wish that you respect their privacy."

Among the scores of Hollywood stars who paid tribute to her, many via Twitter, Ashton Kutcher, with whom she was once romantically linked, was one of the quickest. "Today the world lost a little piece of sunshine," he told his Twitter followers. "My deepest condolences go out to Brittany's family, her husband and her amazing mother Sharon."

The celebrity blogger Perez Hilton similarly expressed his sadness over her death, but added that he had not been entirely surprised. He wrote: "Absolutely devastating. Especially because this comes as no surprise. We, and those who knew Brittany personally, saw this coming."

Angelo Bertolotti, her father, who lives in Florida, told the Associated Press he was stunned to learn of her death. "She was just an absolute doll since she was born," he said. "Her personality was always outward. Everybody loved her – people that made movies with her ... she was just a regular gal."

Mr Hilton had reported recently that things in Puerto Rico went awry because Ms Murphy had "a habit of being difficult on set" and that her husband and handler had got into "a fight with some locals".

Her spokesman denied the claims, however. "The allegations currently circulating on the internet about Brittany Murphy and her husband Simon Monjack read like a fictional plot from one of her 50-plus movies ... she was not nor has she ever been fired from any job big or small. Mr Monjack did not engage in any alleged scuffles. Though due to creative differences Ms Murphy and the production mutually parted ways."