3. As of noon trading, Thoratec Corporation ( THOR) is down $3.73 (-10.2%) to $32.79 on heavy volume Thus far, 3.3 million shares of Thoratec Corporation exchanged hands as compared to its average daily volume of 559,100 shares. The stock has ranged in price between $31.60-$35.36 after having opened the day at $34.79 as compared to the previous trading day's close of $36.52. Thoratec Corporation engages in the development, manufacture, and marketing of proprietary medical devices used for circulatory support. Thoratec Corporation has a market cap of $2.1 billion and is part of the health care sector. The company has a P/E ratio of 38.1, above the S&P 500 P/E ratio of 17.7. Shares are down 4.7% year to date as of the close of trading on Thursday. TheStreet Ratings rates Thoratec Corporation as a buy. The company's strengths can be seen in multiple areas, such as its robust revenue growth, largely solid financial position with reasonable debt levels by most measures, good cash flow from operations, expanding profit margins and increase in stock price during the past year. We feel these strengths outweigh the fact that the company has had sub par growth in net income. Get the full Thoratec Corporation Ratings Report now. Exclusive Offer: Jim Cramer's 'go-to' small/mid-cap guru Bryan Ashenberg only buys stocks he thinks could return 50-100%. See his top picks for 14-days FREE.