NEW YORK (CNNMoney.com) -- Abiomed hit a major medical milestone when the FDA approved its artificial heart, but relatively few people are expected to use it and the company isn't likely to see significant sales from its new product at least a couple years.

Abiomed's (down $0.02 to $15.00, Charts) new device, Abiocor, is the first self-contained artificial heart to win approval from the Food and Drug Administration. The FDA approved the device on Sept. 6.

The first-generation Abiocor (left) and the second-generation Abiocor 2 (right.)

The Abiocor retails for $250,000 and is designed to extend survival in terminally ill patients by up to 18 months. However, the 14 patients who tested the device in clinical trials extended life by an average of about five months. One patient survived an extra 17 months with the artificial heart, but two others died during surgery.

The Abiocor was implanted in terminally ill patients with little to lose. Those who participated in the study but did not receive the Abiocor survived an average of two weeks.

The FDA has capped the Abiocor to 4,000 implants annually. But that number doesn't mean much. Far fewer people are expected to use the grapefruit-sized Abiocor, which at two pounds is too large to be implanted in people with small chest cavities. Chief financial officer Daniel Sutherby did not say how many Abiocor implantations his company expects to perform in the near future, and the company does not include sales projections for the current fiscal year. Also, Abiomed plans to debut the artificial heart at no more than 10 medical clinics, though they include esteemed institutions like Johns Hopkins Hospital in Baltimore and the Jewish Hospital in Louisville.

"You could probably expect the first implant for Abiocor in 2007, but the company is going to be very methodical and slow in rolling this out," said Harish Aiyar, analyst for Dawson James Securities. "[The annual number of implants] is theoretically capped at 4,000, but in this case it's essentially meaningless."

Analysts project up to 40 implants, totaling $10 million in sales, in fiscal year 2008, which ends in March, 2008. Annual sales of $10 million is significant for Abiomed, a relatively small company that has projected $52 million in sales for fiscal year 2007. But the company's other cardiovascular products -- including the AB 5000 Circulatory Support System and the BVS 5000 Biventricular Support System-- are the real growth drivers behind the company. These devices provide mechanical assistance to the heart, putting less pressure on the heart and allowing it to heal.

The recently-approved Abiocor is a prototype model. The Danvers, Mass.-based company is also developing the next-generation Abiocor 2, which is 30 percent smaller and designed to last 5 years.

"Even though [the Abiocor] got FDA approval, everyone is going to treat this very much as an experimental device," said Greg Simpson, analyst for Stifel Nicolaus & Co.

Sutherby, the CFO, said the Abiocor 2 was designed for increased safety related to bleeding, based on lessons learned during the clinical trials.

The company and analysts haven't estimated annual sales for the Abiocor 2, because it's still in development and at least a couple years away from filing to the FDA. But Simpson of Stifel Nicolaus & Co. said the sales potential for the next-generation heart is much greater than the first.

"Can they sell 500 [artificial hearts annually,] when they get the second-generation device?" said Simpson. "I think that's certainly in the realm of possibility. Is 5,000 realistic? I think if the device is good enough, you can certainly sell 5,000."

Though Abiomed is the only company that makes a fully-contained artificial hearts, there are many other companies that make medical devices for the heart, including Medtronic (up $0.01 to $46.42, Charts), St. Jude Medical (up $0.08 to $37.56, Charts) and Guidant (up $0.57 to $80.10, Charts), which is owned by Boston Scientific (down $0.03 to $16.37, Charts).

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