The announcement by team president and CEO Bernie Mullin came 3 1/2 weeks after Atlanta completed a turbulent season by setting team records for wins (33) and points (78).
"Don has done a tremendous job of building this team and assembling what is arguably the most talented young roster in the NHL," Mullin said. "He is one of the most respected general managers in the league.
"We believe that his leadership and expertise will continue to help us shape our club into a perennial contender."
Last September, Heatley was involved in a car accident in which teammate Dan Snyder was killed. Despite the tragedy, Atlanta threatened for the first playoff berth in team history, eventually finishing second in the Southeast Division with a 33-37-8-4 record.