 The character was created by series' producer Shonda Rhimes, and is portrayed by Kim Raver.She was introduced as a recurring character in season six, but is later upgraded to series regular in the same season after Katherine Heigl's departure from the series.Altman was conceived as the third major attending cardiothoracic surgeon in the series, following Preston Burke (Isaiah Washington) and Erica Hahn (Brooke Smith)'s exits.