St. Jude Medical (NYSE:STJ) has been nothing short of great for investors this year, rewarding shareholders with stock gains of 40% since the start of 2013. The company's sales haven't shone with quite the same luster, however, as St. Jude's revenue has fallen around 2% over the year's first six months. It has been a trend with St. Jude and many of the top companies centered around the cardiovascular device space, which have struggled behind a variety of problems besieging the industry lately.

However, St. Jude's looking ahead. The company picked up some good news on Thursday for one of its developing businesses full of potential. Is there something brewing behind the scenes at St. Jude to alleviate this company's woes?

The temptations of a promising market
Renal denervation is a new field in endoscopy used to treat the growing problem of hypertension. It has attracted the attention of many of the big names in the device industry, and St. Jude's no exception. On Thursday, the company picked up European CE Mark approval for the next generation of its EnligHTN renal denervation system, which St. Jude claimed in its press release is more than five times faster in its usage than its first generation of the device.

St. Jude can't afford to slow down in this industry. So far, renal denervation hasn't scratched the big dollars of the company's financial reports, and the global device market for this ailment was estimated at less than $100 million in 2012.

However, analysts are expecting the renal denervation device market to heat up to between $2 billion and $3 billion by 2021. The global hypertension market in all boasts a huge population, with more than 75 million patients in the U.S. alone. Capturing even a small slice of that would provide a huge boost to St. Jude's lagging cardiovascular device sales.

However, rivals are hard on St. Jude's heels here -- and in Medtronic's (NYSE:MDT) case, already out in front. Medtronic's Symplicity renal denervation system picked up CE Mark approval back in 2010 and has emerged as an early leader in this field. Meanwhile, Boston Scientific's (NYSE:BSX) charging ahead after it purchased renal denervation developer Vessix Vascular last year for up to $425 million in all. Vessix's V2 system has already won approvals in Europe and Australia, keeping Boston in line with St. Jude and Medtronic in this promising market. Covidien's (NYSE:COV) OneShot renal denervation device also won CE Mark approval in 2012, and the company launched the device in Europe, Asia, and other international markets early this year.

So far, however, only the international markets have paid off in the renal denervation push. St. Jude overcame a big hurdle in approaching the U.S. market by winning FDA approval to launch an American trial of the EnligHTN earlier this summer, something Medtronic has already achieved. However, it'll be quite some time before the company's even close to winning regulatory approval to launch the device in the U.S.

Keeping steady in the race
What's the outlook on this device -- and promising market -- for St. Jude? So far, it looks like the company's settling into a tenuous second place in this market, with its U.S. trial launch keeping it just ahead of Covidien and Boston. However, this newest generation of EnligHTN approved this week has a critical advantage over Medtronic's leading device: Its four-minute average ablation time is more than nine times faster than Medtronic's Symplicity, which the latter company says averages around 38 minutes for a procedure.

That might not be enough to beat out Medtronic in the race to reach U.S. approval, as Medtronic's aiming at 2015 for an American launch of its device. While St. Jude might not achieve that critical first-mover advantage, the company's in good shape so far in the early development of this young but promising industry. As St. Jude looks to turn around falling sales, keep an eye on the EnligHTN to become a big part of this firm's future.

Fool contributor Dan Carroll has no position in any stocks mentioned. The Motley Fool recommends Covidien. The Motley Fool owns shares of Medtronic. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.