“My speculation would be that he had that sort of event where his heart temporarily stopped,’’ said Becker, who is not involved in Mubarak’s treatment. “That doesn’t mean that it’s irreversible.’’ Life support can be used to keep his blood circulating and replace breathing if he is unable to do so on his own, Becker said.

Mubarak’s condition brought to mind former Israeli Prime Minister Ariel Sharon — though it was not known if there was any medical similarity in their conditions. Sharon, now 84, suffered a massive stroke on 2006. Intensive treatment and repeated operations by a team of brain surgeons stabilized his condition, but he has never regained consciousness and remains on life support in a deep coma.

Mubarak has been serving a life sentence at Torah Prison for failing to stop the killing of protesters during the 18-day uprising against his rule last year. The verdict against him has already been a spark for protests — thousands massed in Tahrir when the court acquitted him and his sons on separate corruption charges and cleared several top security chiefs on the protester killings.

The multiple disputes have turned a moment that was once anticipated by some as a landmark in Egypt’s post-Mubarak transition — the election of the first civilian president in 60 years — into a potentially destabilizing snarl.

Shafiq’s campaign spokesman, Ahmed Sarhan, told a televised news conference that Shafiq won 51.5 percent of the vote and that the claim of victory by Morsi was “false.’’

“Gen. Ahmed Shafiq is the next president of Egypt,’’ Sarhan said. He said Shafiq won some 500,000 votes more than Morsi, of the fundamentalist Brotherhood.

The Shafiq campaign’s claim came just hours after Morsi’s campaign repeated their claims of victory, saying Morsi had won 52 percent of the vote compared to Shafiq’s 48.