What: Shares of Cardiovascular Systems (CSII), a medical device company with a focus on minimally-invasive surgery products used to treat vascular disease, fell more than 15% today after reporting second quarter earnings.

So what: Revenue during the quarter grew 22% to $48.5 million, which was below the low end of the $49 million to $50.5 million range that the company guided for during last quarter's report. Management blamed the shortfall on having a lower than expected sales headcount during the quarter than they were planning. On the bottom line, the company reported a net loss of $0.27 per share, which was better than the $0.30 loss that analysts were expecting. 

During the quarter the company received FDA clearance for its new ViperWire Advance Peripheral Guide Wire with Flex Tip. This product should allow physicians improved access when treating arterial calcium associated with Peripheral Artery Disease, or PAD, and is expected to launch in August.

Looking ahead, the company is guiding for revenue growth of 23% to 27% next quarter, which represents a range of $48.5 million to $50 million, and for net-loss to come in between $0.38 to $0.40 per share.

Now what: The company estimates that as many as 18 million Americans have PAD, which is caused by an accumulation of plaque in the peripheral arteries, and the prevalence of PAD is growing rapidly. The company believes that this market is worth around $12 billion, and that it is well positioned to continue to take advantage of that market opportunity. 

While the company is still losing money, it currently holds more than $80 million in cash on its balance sheet, which should be enough to allow the company to reach profitability if it can continue to grow its top-line strongly. While showing a sales shortfall based on management's own guidance is never a good thing, the opportunity in front of this company certainly looks huge, so today's price movement may represent an attractive entry point for a long-term-oriented investor.