The St Jude device, called the EnligHTN Renal Denervation System, is intended for patients whose high blood pressure is resistant to drug therapy, or about one quarter of those who have hypertension.

An estimated 68 million Americans, or one in three, have high blood pressure, considered a risk factor for heart disease, the world's No. 1 killer.

St Jude has not yet disclosed an expected U.S. launch date for the product, a spokeswoman for the St Paul, Minnesota-based medical device maker said.

Several medical technology companies are investing heavily in developing device-based high blood pressure treatments, and analysts foresee a large potential market.

Jefferies analyst Raj Denhoy expects the first systems to hit the U.S. market in about two years and estimates the worldwide market could grow to $2.8 billion by 2020.

"It's an enormous market. There are literally hundreds of millions of people around the world who could benefit from this," said Jefferies analyst Raj Denhoy said. He noted so far the devices have shown few negative side effects.

Leading U.S. device makers that have already received approval to sell hypertension products in Europe include Medtronic Inc, the frontrunner, and Covidien Inc.

The ablation procedure, known as renal denervation, involves threading a catheter through the renal arteries from the femoral artery in the groin.

The catheter delivers radiofrequency energy to create tiny lesions along the renal sympathetic nerves that help regulate blood pressure. The lesions disrupt the nerve supply to decrease systolic blood pressure, which is the top number in a reading.

St Jude also plans to release study data on the safety and effectiveness of the device on Wednesday at a medical meeting in Paris.

Medtronic in January 2011 completed the acquisition of Ardian Inc, which already has a renal denervation system on the market in Europe. Medtronic paid $800 million upfront for the privately held company and agreed to make further payments tied to revenue growth.

Covidien's OneShot renal denervation system received European regulatory clearance in February, and Frankfurt-based ReCor Medical also won approval for its device in February.

Privately held Vessix Vascular Inc of Laguna Hills, California, announced earlier this month that it received European approval for a renal denervation system.

JPMorgan analyst Michael Weinstein said St Jude's European product launch comes several months ahead of expectations and should help draw investor attention away from recent headlines on failure rates for some St Jude heart defibrillator lead wires.

Cardiac rhythm management (CRM) products such as implanted defibrillators are now St Jude's biggest market.

"While CRM dominates the headlines, the real story and future at St Jude is its pipeline outside of CRM," Weinstein wrote in a note to clients.

Shares of St Jude fell 2 percent to close at $38.89 on the New York Stock Exchange.

(Reporting By Susan Kelly; Editing by Richard Chang)

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