An American woman lost an appeal Monday of her conviction in a Hong Kong court for the beating death of her husband in a sensational case widely known as the "milkshake murder" trial.

Dressed in black, Nancy Kissel nodded her head and appeared to be holding back tears when a judge announced the decision in the Court of Appeal. Kissel, who suffered a knee injury in prison, limped out of the courtroom aided by two policewomen.

The 44-year-old housewife from Minnesota was convicted in 2005 of giving her husband a milkshake laced with sedatives in 2003 and then fatally bashing the wealthy banker on the head with a metal ornament.

Kissel said she was defending herself from an abusive husband and appealed the conviction and her life sentence in prison. But prosecutors argued Kissel was a cold-blooded wife who planned the attack in the couple's luxury apartment.

Defense attorney Simon Clarke said he was "very disappointed" but not surprised by Monday's ruling.

"This court doesn't uphold many appeals at all," Clarke said. "But we are expecting a better hearing at the Court of Final Appeal."

The three-judge panel did not give approval for the case to proceed to a higher court, and Kissel will need to apply for permission to get the Court of Final Appeal to hear the case.

The defendant's mother, Jean McGlothlin, said her daughter was fragile physically. But she added: "Her spirit is strong. Her will is strong. Her heart and mind are strong."

The sensational trial has made headlines worldwide because of its allegations of drug abuse, kinky sex and adultery in the wealthy world of expatriates in this Asian financial center.

Kissel said her then 40-year-old husband, Robert, an investment banker for Merrill Lynch, was an erratic whiskey-swilling workaholic who also snorted cocaine and forced her to have painful anal sex. She testified that she killed him as he was threatening her with a baseball bat in a quarrel.

During the appeal hearings, Kissel's defense lawyer said the woman suffered an abnormality of mind that substantially impaired her self-control.

But prosecutors argued that Kissel was a scheming woman who plotted to kill her husband.

They said Robert Kissel of New York had been angry about his wife's affair with a repairman who worked on the couple's vacation home in the northeastern U.S. state of Vermont. He had planned to seek a divorce just before she killed him.

Robert Kissel's estate was worth $18 million in life insurance, stocks and properties before he was murdered, prosecutors said.