AGA Medical ( AGAM) was the biggest percentage gainer in the last five sessions, rising 42.7% to $20.99. A deal to be acquired by St. Joe Medical ( JOE) for $1.8 billion will do that. Announced on Oct. 18, the deal then valued AGA Medical shares at $20.80 each in a combination of cash and stock. St. Joe commenced the tender offer for AGA Medical's shares on Wednesday. AGA Medical shares were down slightly for the year before St. Joe's offer came in, trading at just $14.71 ahead of the announcement. The Plymouth, Minn.-based maker of heart defect products is slated to report its third-quarter results on Nov. 8 with Wall Street forecasting earnings of 11 cents a share on revenue of $54.6 million. St. Joe is aiming to complete the acquisition of AGA Medical by the end of the year, and it's expecting revenue growth in the low single digits from the franchise in 2011.