News Release

Patient Enrollment Now More than 70 Percent Complete

ST. PAUL, Minn.--(BUSINESS WIRE)--Jul. 2, 2012-- Cardiovascular Systems, Inc. (CSI) (NASDAQ: CSII), a medical device company developing and commercializing innovative interventional treatment systems for vascular disease, today announced that two patients at two different hospitals were treated with its new, 6 French guide catheter-compatible, electric orbital atherectomy system. The treatments are part of CSI’s ORBIT II trial, which is now over 70 percent enrolled. ORBIT II is evaluating the safety and effectiveness of CSI’s orbital technology in treating calcified coronary arteries.

Dr. Rohit Bhatheja, an interventional cardiologist at Florida Hospital Orlando in Orlando, Fla., and Dr. Rakesh Shah, an interventional cardiologist at St. Mary Medical Center in Langhorne, Pa., enrolled the first patients with the new electric coronary system. Dr. Bhatheja said, “This new electric system is very easy to use, and the setup time only takes a few seconds.” Dr. Rakesh added, “The new lower profile system allows me more access site options, so I can treat a broader patient population.”

According to David L. Martin, CSI president and CEO, “Treating patients with our most advanced coronary system in the ORBIT II trial is a key accomplishment, as we work to secure a coronary indication in the United States. Using orbital technology in calcified coronary arteries may lead to a new treatment paradigm for more effective stent placement, avoiding the trauma and cost of retreatment or heart bypass surgery. Our technology showed excellent results in the ORBIT I feasibility trial, and we anticipate similar results in ORBIT II.”

CSI’s orbital technology is well suited for removing calcific and fibrocalcific plaque in coronary lesions. This new coronary system underscores CSI’s technology leadership in treating calcified arteries with a simpler design that gives physicians complete control of device operation. Additionally, the system uses CSI's orbital mechanism of action that protects healthy tissue while removing even the most difficult to treat plaque. The advanced, electric-powered handle features a power on/off button and speed selection controls conveniently positioned for ease of use and greater physician control. By eliminating the compressed air tank and separate speed controller of the previous coronary systems, CSI’s new system significantly reduces device set-up and lab-staff time.

CSI received unconditional FDA IDE approval for the ORBIT II study in April 2010, and more than 45 U.S. medical centers are enrolling patients. The company expects to complete patient enrollment early fall of 2012. Dr. Jeffrey Chambers, an interventional cardiologist with Metropolitan Cardiovascular Consultants, Minneapolis, is the principal investigator for the ORBIT II study. The primary endpoints of ORBIT II are based on a 30-day patient follow-up post procedure, and CSI expects to submit a Premarket Approval (PMA) application to the FDA soon after enrollment completion.

A coronary application of CSI’s orbital technology would open up a large, underserved opportunity for the company. CSI estimates coronary market potential to be in excess of $1.5 billion.

About Cardiovascular Systems, Inc.
Cardiovascular Systems, Inc., based in St. Paul, Minn., is a medical device company focused on developing and commercializing innovative solutions for treating vascular and coronary disease. The company’s Diamondback Orbital Atherectomy System treats calcified and fibrotic plaque in arterial vessels throughout the leg in a few minutes of treatment time, and addresses many of the limitations associated with existing surgical, catheter and pharmacological treatment alternatives. The U.S. FDA granted 510(k) clearance for the use of the Diamondback Orbital Atherectomy System in August 2007. To date, more than 66,000 PAD procedures have been performed using CSI’s technology in leading institutions across the United States. CSI has also commenced its ORBIT II Investigational Device Exemption clinical trial to evaluate the safety and effectiveness of its orbital technology in treating coronary arteries. The coronary system is limited by federal law to investigational use and is currently not commercially available in the United States.

For more information, visit the company’s website at www.csi360.com.

Safe Harbor
Certain statements in this news release are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and are provided under the protection of the safe harbor for forward-looking statements provided by that Act. For example, statements in this press release regarding (i) CSI’s clinical trials, including anticipated results in ORBIT II, CSI’s expectation that it will complete patient enrollment in its ORBIT II clinical trial this summer or early fall 2012, and CSI’s expectation that it will submit a PMA application soon after enrollment completion; (ii) the potential for securing a coronary application in the United States; and (iii) the large, underserved market opportunity for CSI that a coronary application of CSI’s orbital technology would open up and the market potential of a coronary application, are forward-looking statements. These statements involve risks and uncertainties which could cause results to differ materially from those projected, including but not limited to the potential for unanticipated delays in enrolling medical centers and patients for clinical trials; dependence on market growth; the reluctance of physicians to accept new products; the effectiveness of the Diamondback™ Orbital Atherectomy System; actual clinical trial results; the impact of competitive products and pricing; the difficulty to successfully manage operating costs; fluctuations in quarterly results; FDA clearances and approvals; approval of products for reimbursement and the level of reimbursement; general economic conditions and other factors detailed from time to time in CSI’s SEC reports, including its most recent annual report on Form 10-K and subsequent quarterly reports on Form 10-Q. CSI encourages you to consider all of these risks, uncertainties and other factors carefully in evaluating the forward-looking statements contained in this release. As a result of these matters, changes in facts, assumptions not being realized or other circumstances, CSI's actual results may differ materially from the expected results discussed in the forward-looking statements contained in this release. The forward-looking statements made in this release are made only as of the date of this release, and CSI undertakes no obligation to update them to reflect subsequent events or circumstances.

Product Disclosure
The Diamondback Orbital Atherectomy System is indicated for use as therapy in patients with occlusive atherosclerotic disease in peripheral arteries and stenotic material from artificial arteriovenous dialysis fistulae. The system is contraindicated for use in coronary arteries, bypass grafts, stents or where thrombus or dissections are present. Although the incidence of adverse events is rare, potential events that can occur with atherectomy include: pain, hypotension, CVA/TIA, death, dissection, perforation, distal embolization, thrombus formation, hematuria, abrupt or acute vessel closure, or arterial spasm.

Source: Cardiovascular Systems, Inc.

For Cardiovascular Systems, Inc.
Investor Relations
651-259-2800
investorrelations@csi360.com
or
Sarah Wozniak
651-259-1636
swozniak@csi360.com
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Padilla Speer Beardsley:
Matt Sullivan
612-455-1709
msullivan@padillaspeer.com
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Dave Folkens
612-455-1741
dfolkens@padillaspeer.com