Innovative med tech stock Edwards Lifesciences (NYSE:EW) has been one of the most exciting stocks to watch in the medical device industry lately. Shares have fallen over the past year, but Edwards' battle to secure dominance in the transcatheter aortic heart valve market, particularly in the U.S., where it won the first approval of a device of its kind for its Sapien heart valve, has been an intense battle. On the other side of the fight, rival Medtronic (NYSE:MDT) has remained hot on Edwards' heels, and this year has looked primed to knock down the company's leadership in the U.S. by securing Food and Drug Administration approval for its own competing CoreValve heart valve.

But not so fast, says Edwards. The company on Monday won a legal victory against the CoreValve after a U.S. court placed an injunction against Medtronic's device's sales. While Medtronic answered with a motion to stay that injunction, it will need to file an appeal to continue its momentum in the U.S. market -- and Edwards has one critical time to cement its place as the American leader in this niche before Medtronic and other companies can chip away at its market share.

Can Edwards' stock rally and the Sapien keep sales growth churning higher? In the video below, Motley Fool contributor Dan Carroll takes you through all you need to know regarding the latest in the battle between these two fierce med tech rivals and whether Edwards' stock can emerge as a long-term winner for your portfolio.