LOS ANGELES ? Hollywood icon Elizabeth Taylor is to undergo a heart operation to repair a "leaky valve," the iconic Oscar-winning actress announced Tuesday.

The 77-year-old English-born movie legend said in a post on micro-blogging site Twitter that she was to have a new procedure that would not involve open heart surgery.

"Dear Friends, I would like to let you know before it gets in the papers that I am going into the hospital to have a procedure on my heart," the actress tweeted.

"It's very new and involves repairing my leaky valve using a clip device, without open heart surgery, so that my heart will function better.

"Any prayers you happen to have lying around I would dearly appreciate. I'll let you know when it's all over. Love you, Elizabeth."

Taylor's health has been the subject of intense speculation in recent years. In 1997 she underwent surgery to have a brain tumor removed and in 2006 she appeared on US television to deny rumors she had Alzheimer's.

In July 2008 she was hospitalized in Los Angeles but her spokesman denied reports that she was close to death and had been placed on life support.