Actress Dame Elizabeth Taylor shared bad news with her fans via her Twitter website.
She is to undergo heart surgery.The procedure involved "repairing my leaky valve using a clip device, without open heart surgery, so that my heart will function better".
The 77-year-old said she wanted her Twitter followers to "know before it gets in the papers". "Any prayers you happen to have lying around I would dearly appreciate," she added. "I'll let you know when it's all over. Love you, Elizabeth."
The actress - made an honorary dame by the Queen in 2000 - has had a number of health problems in recent years.
In 1995, the actress had a hip replacement and, two years later, had surgery to remove a brain tumour.
She has the brittle bone disease osteoporosis and has broken her back five times.
Known for her acting skills and beauty, as well as her Hollywood lifestyle, including many marriages, Taylor is considered one of the great actresses of Hollywood's golden years, as well as a larger-than-life celebrity. Dame Elizabeth won best actress Oscars for Butterfield 8 and Who's Afraid of Virginia Woolf?
BBC News contributed to the report.