When did the Vice President begin to suffer his heart attack?

Vice President Cheney arrived at George Washington University Hospital about 8:00 a.m. local time. He will be in surgery several hours, and if there are no complications, expects to return home Saturday afternoon.
    Doctors say the out patient procedure does not mean the vice-president’s heart condition is getting worse. Mr. Cheney says he feels fine, that he hasn’t noticed the irregular heart rhythms that were picked up by a monitor two weeks ago. He said the pacemaker to control those irregular rhythms will not affect his ability to serve as vice president.
    Mr. Cheney’s history of heart disease was an issue during the presidential campaign. Last year, he suffered his fourth heart attack since 1978. As vice-president, Mr. Cheney has lost 25 pounds with more exercise and a special diet maintained by Navy chefs.
    The White House says there are no plans to reduce the vice-president’s schedule after Saturday’s procedure. Mr. Cheney told reporters he expects to be back at work Monday morning.