Congress has failed to end the threat of a 21% payment cut for doctors who participate in Medicare. The Senate could vote as soon as Wednesday to end debate on a bill to delay the cuts, but lawmakers are considering postponing them just through the year's end. A House bill that passed last month would delay the cuts through the end of 2011. Repeated short-term fixes of the problem in recent years have left doctors frustrated and some are refusing to take new Medicare patients. Since the latest "doc fix" expired May 31, doctors have been holding off on submitting claims until Congress approves another patch, the Wall Street Journal reports.