Former President Bill Clinton was breathing without a respirator Tuesday morning as he recovers from an operation that likely saved him from an imminent heart attack. Doctor Bob Kelly of Clinton`s surgery team said taking Clinton off the respirator last night was a major step in his recovery. That puts him on track to leave New York Presbyterian Hospital in four or five days. Clinton`s heart disease was extensive, so severely clogging his arteries that doctors feared he would have a heart attack if they didn`t operate over the weekend. They actually stopped the former Arkansas governor`s heart for a time during the procedure and used two arteries from his chest and one from his leg to detour around the clogged passageways.