Few industries in the medical device sector have been as hard-hit in recent years as the cardiac rhythm management, or CRM, business. One look around the industry tells it all. Medtronic's (NYSE:MDT) cardiac rhythm disease management business lost 2% of its sales year over year in its most recent fiscal year, led by its lagging defibrillator business. Boston Scientific (NYSE:BSX) followed closely in its larger rival's footsteps, as its own implantable cardioverter defibrillator products, or ICDs, saw sales fall nearly 4% in the most recent quarter.

Yet no company's as at risk to the CRM market's downturn as St. Jude Medical (NYSE:STJ). St. Jude's even more reliant on defibrillators for its revenue than either Boston Scientific or Medtronic, as the company pulls in more than 30% of its total sales from the products. The business' downturn has taken a toll on St. Jude's finances even as this surging stock has soared in 2013.

Finally, however, hope is rising for the future. St. Jude released its third-quarter earnings Wednesday, and the results from its defibrillator business at long last showed growth. Can this result turn around St. Jude's fortunes? In the video below, Motley Fool contributor Dan Carroll tells you what you need to know about St. Jude's most important segment and whether the CRM industry can continue these gains as Medtronic and Boston Scientific report earnings in the coming weeks.

Fool contributor Dan Carroll has no position in any stocks mentioned. 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.