NEW YORK (AP) -- Medical device maker Medtronic Inc. said Thursday it will buy Cryocath for about $380 million in a move to expand its treatment portfolio for heart conditions, including abnormal heart rhythms.

Minneapolis-based Medtronic said it will pay $8.75 Canadian per share, or $400 million Canadian ($380 million), to buy the remaining shares of Montreal-based Cryocath. The deal represents a 97 percent premium to CryoCath's closing price on Sept. 24, which was 4.44 Canadian dollars on the Toronto Stock Exchange.

CryoCath's key product is its Arctic Front system, which treats abnormal heart rhythms using cryoablation technology. The technique uses cold to restore a normal heart rhythm.

"Medtronic's offer reflects its endorsement of our cryoablation technology and the role that our flagship product, Arctic Front, will play in treating atrial fibrillation (abnormal heart rhythm) patients around the world," said Jan Keltjens, president and chief executive of CryoCath.

Medtronic estimates that up to 5 million patients worldwide are affected by abnormal heart rhythm.

CryoCath's board of directors has already unanimously recommended shareholders approve the buyout and it is expected to close during the fourth quarter.