"This is a great agreement for Senators fans, Dany, the organization and NHL hockey in Ottawa for years to come," said Eugene Melnyk, the franchise's owner.
Heatley, the second pick in the 2000 draft, has scored 180 goals with 209 assists during a five-year career.
He had 50 goals last season, which was his second in Ottawa after coming to the Senators in a trade with Atlanta.
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