Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Thoratec (Nasdaq: THOR), whose devices aid with circulation, fell more than 15% after management reduced its full-year outlook. The stock closed off 12.7%.

So what: Third-quarter revenue grew 13% but came up short of expectations. Adjusted earnings improved 28% to $0.41 a share, well above Wall Street's $0.34-per-share target, but weak sales weighed on 2011 guidance. Thoratec now expects sales to come in between $418 million to $423 million this year, down from earlier estimates of $422 million to $430 million.

Now what: Though the miss and decline must to be disappointing to some, the stock has to be nearing an attractive entry point for the equity analysts at Canaccord Genuity. They list Thoratec alongside AtriCure (Nasdaq: ATRC) and Volcano (Nasdaq: VOLC), among others, as a likely buyout candidate. Do you agree? Would you buy shares of Thoratec at current prices? Please weigh in using the comments box below.

Interested in more information about Thoratec? Add it to your watchlist.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team. He didn't own shares in any of the companies mentioned in this article at the time of publication. Check out Tim's portfolio holdings and Foolish writings, or connect with him on Google+ or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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