From TMZ.com-
"TMZ has the inside dirt on a feud between Patrick Dempsey and Isaiah Washington that bubbled over on the "Grey's Anatomy" set this week.
According to the NY Daily News' Rush & Molloy, Washington said "some disgusting things" and got in Dempsey's face. The National Enquirer kicked it up a notch, reporting the Washington had shoved Dempsey and choked him."