JERUSALEM (AP) – Israel’s turbulent political scene, largely frozen since Ariel Sharon’s stroke last week, jumped back to life on Thursday with the hard-line Likud Party choosing candidates for upcoming parliament elections and word that acting Prime Minister Ehud Olmert may soon visit the White House.

As Sharon was in an a coma for the eighth day, medical experts raised new questions about whether treatment with blood thinners he received after an earlier stroke contributed to last week’s massive brain hemorrhage.

Sharon remained in critical but stable condition Thursday at Jerusalem’s Hadassah Hospital, where doctors continued efforts to end his sedation. The hospital said his heart rhythm was normal, and he would undergo a routine brain scan later in the day.

Hospital officials denied comment on a report in the Maariv daily Thursday that Sharon’s medical team as saying his heart began to beat irregularly when doctors tried to scale down the sedatives. The newspaper quoted a member of Sharon’s medical team, but did not identify its source.

Ending the sedation, which has kept Sharon in an induced coma for the past week, is a key step toward assessing the damage from the stroke. Hospital spokesman Ron Krumer said it was unclear when the sedation would be halted.

Sharon has moved his hands and right leg in response to pain stimuli in recent days, according medical officials. The hospital said he showed slight progress on Wednesday, but doctors say it will be days, perhaps weeks, before a full picture of damage emerges.

“One of the most important stages in the process is opening the eyes,” Dr. Jose Cohen, one of Sharon’s surgeons, told Israel TV. “Most patients open their eyes within the first three weeks. The sooner they open their eyes the better. We don’t know when he will do it.”

With Sharon apparently out of immediate danger, the rough-and-tumble Israeli political system got back down to business on Thursday.

A government official said Acting Prime Minister Ehud Olmert may travel to Washington for talks at the White House. The official declined to be identified because a formal invitation has not yet been received. The U.S. Embassy in Tel Aviv said it had no information about the matter.

Since Sharon’s stroke, Olmert has worked to project stability, holding Cabinet meetings and assuring the country that the government continues to function.

Olmert had previously been seen as an unlikely candidate for prime minister, but his calm stewardship of the crisis has turned him into the clear front-runner in the March 28 election.

Sharon’s new centrist party, Kadima, has increased an already commanding lead in post-stroke opinion polls, easing concerns that it might fall apart in the absence of its leader. Sharon quit Likud to form Kadima, saying it would give him more flexibility to pursue a peace deal with the Palestinians.

The Likud’s Central Committee was choosing its list of candidates Thursday for the election. Polls have shown the party, decimated by the loss of Sharon and other leading politicians, could lose more than half its seats in the 120-member parliament.

Since Sharon’s stroke, Israeli media have begun to question the treatment he received after an earlier, mild stroke on Dec. 18. With Sharon’s life out of immediate danger, those questions have gained momentum.

Doctors prescribed blood thinners to Sharon after the first stroke, even though the medication raised the risk of hemorrhaging. The hospital disclosed this week that Sharon suffered from a disease of the brain vessels, cerebral amyloid angiopathy, that could make him particularly susceptible to hemorrhaging.

Dr. Amos Korczyn, head of the neurology department at Tel Aviv University and not involved in the treatment, said Sharon’s doctors should not have prescribed the blood thinners in light of the brain condition.

“It’s clear that if someone has a disease that could cause bleeding, giving anticoagulants like this … is certainly an undesirable situation,» he told Army Radio. But other outside experts said the medical team appeared to have made an appropriate decision. The blood clot that caused the earlier stroke passed through a small hole in Sharon’s heart, and doctors prescribed the medication to prevent a recurrence.

“The blood clot in the heart would be more of a risk than the CAA,” said Dr. Nick Lossef, a neurologist at University College Hospital in London. These are all very difficult decisions,” he added.

“These are situations where no one really knows what the right thing to do is or what the wrong thing to do is.”

Hospital officials have defended their treatment. Dr. Yair Birenboim, a senior official at Hadassah, said the blood thinners were rescribed based on a “consensus of experts” that carefully weighed the pros and cons of the treatment.

“Everyone can be intelligent in hindsight,” he told Army Radio on Wednesday. “This is part of the art of medicine,” he added. “We have to consider things from here and there and decrease the damage as much as possible.”