UPDATE: Piper Jaffray Upgrades Thoratec to Overweight

According to Piper Jaffray, Thoratec

is upgraded to Overweight. Piper Jaffray said that it is upgrading THOR to Overweight as it believes the eventual entry of competitor HTWR into the US market has been sufficiently integrated into THOR's stock valuation. “For Q411, Thoratec's performance was slightly above expectations and with surprising 16% (adjusted) unit growth for THOR's core HeartMate II®, we do see the potential for revenue upside in 2012. OW rating and $37/share price target.” Thoratec closed yesterday at $30.81.