Thoratec Corp. (THOR) said its fourth-quarter net income surged 73% behind rising sales of its pumping device for patients awaiting heart transplants, and that it anticipates U.S. regulatory approval to use that device for people who need permanent help in the first half of 2010.

Thoratec sales in the quarter topped Wall Street estimates while annual sales topped the company's most recent guidance. The Pleasanton, Calif., company issued 2009 guidance with a sales range mostly beneath Wall Street's forecast, however.

Shares, which are down about 16% on the year after soaring nearly 79% in 2008, were recently down 1.7% after-hours after climbing 2.4% to $27.17 during Thursday's regular trading session.

The so-called "destination therapy" market for Thoratec's HeartMate II device, in which heart-failure patients who aren't transplant candidates are treated, is expected to be the product's biggest market.

Thoratec expects to submit its application with the Food and Drug Administration for the destination market this May, which is consistent with a recently bumped-up forecast for a first-half 2009 filing. HeartMate II is approved today for future transplant patients.

The company posted net-income of $6.4 million, or 11 cents per share, up from $3.7 million, or 7 cents a share, a year earlier. Excluding items such as share-based compensation expense, the company said it earned 16 cents a share versus 11 cents.

Analysts surveyed by Thomson Reuters had forecast, on average, earnings of 14 cents a share in the recent quarter.

Sales jumped nearly 34% to $85.7 million, topping Wall Street's forecast by more than $4 million.

Sales of $313.6 million for the year, meantime, topped the range of $302 million to $308 million Thoratec had projected in October, when it raised guidance.

Gary F. Burbach, Thoratec's president and chief executive, said the company continues to see "better than expected adoption" of the HeartMate II device by new centers.

The adoption rate will cool off in 2009, however, which means less customer stocking that helps sales, Burbach noted.

Looking ahead, Thoratec forecast 2009 sales of $345 million to $355 million. Analysts had targeted $353.7 million, on average.

Thoratec expects to post per-share earnings of 41 cents to 47 cents, or 70 cents to 76 cents excluding items. Analysts had forecast 72 cents.

-By Jon Kamp, Dow Jones Newswires; 617-654-6728; jon.kamp@dowjones.com