Cardiovascular Systems, Inc.NASDAQ: CSII

JMP Securities 2017 Life Sciences ConferenceJune 21, 2017

Safe Harbor

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FORWARD-LOOKING STATEMENTSCertain statements made in this presentation 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. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “would,” “expect,” “plans,” “anticipates,” “believes,” “estimates,” “projects,” “predicts,” “potential” and similar expressions intended to identify forward-looking statements. Examples of these statements include, but are not limited to, statements regarding Cardiovascular System, Inc.’s (“CSI” or the “Company”) future financial performance, product sales distribution, industry and market expectations and estimates, the benefits and uses of the Company’s products, market opportunity potential, clinical trials, international expansion, regulatory approvals, future profitability, debt capacity, use of proceeds, results of operations, prospects, plans and

objectives of management, and other statements that are other than statements of historical fact.

These statements involve risks and uncertainties which could cause results to differ materially from those projected, including those described under the heading “Risk Factors” contained in the prospectus filed with the Securities and Exchange Commission (the “SEC”) for our recent public offering, and as detailed from time to time in CSI’s SEC reports, including its Reports on Form 10-K and Form 10-Q. 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 presented. The forward-looking statements are made only as of the date of this presentation, and CSI undertakes no obligation to update them to reflect subsequent events or circumstances.

Investment Merits

• Multibillion dollar, underserved markets in peripheral and coronary artery disease

• Orbital atherectomy: highly differentiated technology– Uniquely and safely treats calcified arterial plaque

– Effective in small vessels

– Supported by medical evidence, published in peer-reviewed journals

• Positioned for sustainable, profitable growth– Stable reimbursement

– Large, clinically-focused U.S. sales force

• Sales synergy between PAD/CAD applications

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Only 2.6 Million Receiving Treatment

700,000 CLI

Peripheral Artery Disease (PAD)Large, underdiagnosed and underserved patient population

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Sources: Sage Group, Millennium Research Group “US Markets for Peripheral Intervention Devices 2014,” iData “US Market for Peripheral Vascular Devices and Accessories” 2014, and Go, et al “Heart Disease and Stroke Statistics -- 2014 Update,” Circulation.

1.9 Million Claudicant

Up to 18 Million in U.S. with PAD, ≈4 Million with Critical Limb Ischemia

(CLI)

2.6 Million Treated

PAD Calcium ≈ $2B U.S. Opportunity

*CSI estimates

160,000 Amputations

470,000 Interventions

2.0MMedical

Management

170,000Interventions

150,000 Amputations

≈2.6M PAD Treatments70% ATK, 30% BTK

≈580,000* with Calcified Lesions≈50% ATK, 50% BTK

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160,000Medical

Management

CAD Severe Calcium ≈ $700M Opportunity

880,000PCI

250,000 CABG

CABG, 250M

* 12% severe calcium in both PCIs & CABG + 48,000 estimated CHIP patientsBourantas,C et al; Heart, 2014;0:1–7. 20% severe Ca++ in DES trialsGénéreux, P. et al. J Am Coll Cardiol 2014;63(18):1845-54. 6% severe Ca++ in ACSFeldman D. et al, Circulation. 2013;127:2295-2306. 60% of PCIs ACS, 40% stable 12% severe Ca++

100,000 PCI

30,000CABG

≈178,000* Patients with Severely Calcified Lesions

≈1.25 Million Coronary Artery Disease (CAD) Procedures and Estimated CHIP Patients

48,000CHIP Patients

CHIP: Complex Higher-Risk Indicated Patients

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120,000CHIP Patients

Crowns shown are not to scale and for illustrative purposes only.

CSI Orbital Atherectomy Systems (OAS)Differential Sanding:

• Eccentrically mounted crown bi-directionally sands hard plaque

• Healthy, elastic tissue flexes away from crown to minimize vessel damage

Centrifugal Force:

• Increasing speed = increased orbit radius

• 360° crown contact designed to create a smooth, concentric lumen

• Allows constant blood flow and particulate flushing during orbit

• Treat large vessels through small sheaths, multiple vessels with one crown

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Benefits of Orbital Atherectomy

Above the Knee

Heart

Below the Knee3

With systems for coronary or peripheral indications, the CSI product line offers heart-to-heels capability.

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3• Heart-to-heels solution• Alternate access sites• Effective in calcium• Excellent safety• Long-term durability• Economical

• 93% < red blood cell size

• 99% < lumen size of capillaries

Unique Mechanism of ActionBi-directional and differential sanding

Calculation of mean particulate size is based on particles larger than 1 micron from a representative study using carbon blocks and cadaver model systems. 9

Leadership in Clinical Evidence

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LIBERTY 360°(Enrollment Complete)

ORBIT II(3-year Data)

COAST(Enrollment Complete)

OASIS, CONFIRM series, CALCIUM 360 and COMPLIANCE 360

• Supported 2nd Gen OAS in U.S. and Japan approval• Japan reimbursement anticipated in late CY17

• 92% freedom from revascularization at 3-years• Up to $4,946 per patient cost savings at 2-years

• High rates of procedural success and durability• Low adverse events/bail-out stenting

• “All-comers” trial vs. any other treatment• Nearly 700 Rutherford class 4, 5, or 6

n=1,204

n=100

Trial ImportanceSize

n=3,359

PAD

CA

D

n=443

5000+Patients

7000Lesions

600Physicians

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OPTIMIZE (Enrolling)

n=50 • OAS + DCB vs. DCB alone• Calcified below-the-knee lesions

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ECLIPSE(Enrollment Began

March 2017)

• Largest randomized trial to study coronary atherectomy for calcified coronary lesions

• OAS + DES vs. angioplasty + DESn=2,000

6-Month ResultsRutherford Classification

RC 2-3 RC 4-5 RC 6

Freedom from (FF) MAE 92.6% 81.2% 73.7%

FF Major Amputation 99.8% 96.8% 87.1%

FF TVR 93.0% 83.1% 85.1%

FF Death 97.1% 95.3% 85.1%

• Patients maintained good outcomes and positive changes in Rutherford classification.

• High freedom from Major Adverse Events (MAE) across all classes.

• Watchful waiting in RC 2-3 and primary amputation in RC 6 may not be necessary.

• 78% of RC 6 subjects were discharged to home.

LIBERTY 360° 6-Month Results

Gray, LIBERTY, ISET, Feb. 6, 2017Adams, LIBERTY, AMP, Aug. 11, 2016 11

Change in Rutherford Classification (RC) Following Endovascular Intervention

0

1

2

3

4

5

6

Baseline 30 Days 6 Months

Rutherford 2-3 Rutherford 4-5 Rutherford 6

AHA/ACC* Guidelines Support PAD Intervention

• 2016 Guidelines on the Management of Patients with Lower Extremity PAD support data in LIBERTY 360

– Revascularization is a reasonable treatment option for claudicants with inadequate response to medical management and exercise

– CLI patients should receive an evaluation for revascularization prior to amputation

*American Heart Association/ American College of Cardiology12

Principal investigators: Philippe Généreux, Ajay Kirtane; Study chairman: Gregg W. StoneSponsor: Cardiovascular Systems Inc.

Orbital Atherectomy Strategy

(1.25 mm Crown followed by non-compliant balloon optimization)

Conventional Angioplasty Strategy

(conventional and/or specialty balloons per operator discretion)

2nd generation DES implantation and optimization

2nd generation DES implantation and optimization

Randomize1:1

Primary endpoints: 1) Post-PCI minimal stent area assessed by OCT (N≈400 in imaging study) 2) 1-year TVF (all patients)

≈2000 pts with severely calcified lesions; ≈60 US sites

ECLIPSE Trial DesignEvaluation of Treatment Strategies for Severe CaLcifIc Coronary Arteries:

Orbital Atherectomy vs. Conventional Angioplasty Prior to Implantation of Drug Eluting StEnts

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Consistent, Attractive Reimbursement

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Hospital Procedure 2017 Reimbursement% Change from 2016

Inpatient PAD $10,593-$19,754 4%-3%

Inpatient CAD $10,072-$19,396 1%-1%

Outpatient PAD/CAD $9,727-$14,511 2%-(1%)

Non-Hospital Facility

Procedure 2017 Reimbursement% Changefrom 2016

Outpatient PAD (ATK) $10,957-$14,853 (2%)-(2%)

Outpatient PAD (BTK) $10,804-$13,371 (2%)-(2%)

MS-DRG 246, 247, 248, 249, 250, 251, 252, 253, 254; CPT Codes 37225, 37227, 37229, 37231, 92933; C-APCs 5191,5192,5193,5194; HCPCS Code C9602

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$0

$50

$100

$150

$200

FY13 FY14 FY15 FY16 FY17(9 Mos.)

Track Record of Revenue Growth FY16 Slowed by Sales Force Transition

Return to Growth in FY17

$ M

illio

ns

Amounts exclude revenue from distribution agreement terminated on 6-30-15

+17%

Strong, Improving Gross Margins

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70%

75%

80%

85%

FY13 FY14 FY15 FY16 FY17(9 Mos.)

78.9%80.1%

77.2%78.0%

80.4%*

Attractive ASPs, Declining Unit Costs

Amounts exclude gross margin from distribution agreement terminated on 6-30-15* FY17 gross margin of 80.4% includes $1.5M charge related to product recall

Achieved Positive Adjusted EBITDA

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$129.7

$152.0

FY16(9 Mos.)

FY17(9 Mos.)

Revenue Adjusted EBITDA

$ m

illio

ns

Reconciliations of Adjusted EBITDA to the most comparable U.S. GAAP measure for the respective periods can be found in the appendix

Leveraging Revenue Growth for Profitability

-$37.8

$8.9

FY16(9 Mos.)

FY17(9 Mos.)

Solid Cash PositionSufficient Cash to Implement Strategy

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$61 $58

$79

$103

$0

$20

$40

$60

$80

$100

$120

Q4 FY16 Q1 FY17 Q2 FY17 Q3 FY17

$ M

illio

ns

• Positive FY17 cash flow from operations • $21M proceeds from sale-leaseback transaction (Mar. 2017)• $10M proceeds from Japan distribution agreement (Nov. 2016)• $40M line of credit in place

Why CSI?

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• Multibillion dollar, underserved markets in peripheral and coronary artery disease

• Orbital atherectomy: highly differentiated technology– Uniquely and safely treats calcified arterial plaque

– Effective in small vessels

– Supported by medical evidence, published in peer-reviewed journals

• Positioned for sustainable, profitable growth– Stable reimbursement

– Large, clinically-focused U.S. sales force

• Sales synergy between PAD/CAD applications

Appendix

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Peripheral angiography pre-procedure (A), post-OAS (B), and post-procedure (C). The magnified view of the lesion of interest is indicated in a, b, and c.Gray-scale IVUS images (D and D’) and echogenicity analyses (E, E’ and Table) correspond to the yellow arrowhead in a and b. IVUS = intravascularultrasound OAS = orbital atherectomy system.

IVUS Echogenicity Analysis Pre- & Post-OAS

Sotomi, JACC: Cardiovascular Interventions, 201521

Non-GAAP Reconciliations

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Non-GAAP Financial MeasuresTo supplement CSI's consolidated condensed financial statements prepared in accordance with GAAP, CSI uses a non-GAAP financial measure referred to as "Adjusted EBITDA" in this presentation. An explanation of the manner in which CSI's management uses Adjusted EBITDA to conduct and evaluate its business, the economic substance behind management's decision to use Adjusted EBITDA, the substantive reasons why management believes that Adjusted EBITDA provides useful information to investors, the material limitations associated with the use of Adjusted EBITDA and the manner in which management compensates for those limitations can be found in CSI’s most recent quarterly earnings release, dated, May 3, 2017.

ADJUSTED EBITDA RECONCILIATION Nine Months Ended$ in thousands Mar. 31, 2017 Mar. 31, 2016

Net Income (loss) $(2,564) $(51,140)

Less: Other (income) and expense, net (46) (22)

Less: Provision for income taxes 66 57

Income (loss) from operations (2,544) (51,105)

Add: Stock-based compensation 8,336 10,392

Add: Depreciation and amortization 3,100 2,900

Adjusted EBITDA $8,892 $(37,813)

Q3 FY 2017 Statement of Operations

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(Dollars in thousands, except per share and share amounts)

Q3 FY 2017 Balance Sheet

24

(Dollars in thousands, except per share and share amounts)

Q3 FY 2017 Statement of Cash Flows

25

(Dollars in thousands)

DIAMONDBACK 360® Coronary Orbital Atherectomy System

Indications: The DIAMONDBACK 360® Coronary Orbital Atherectomy System (OAS) is a percutaneous orbital atherectomy system indicated to facilitate stent delivery in patients with coronary artery disease (CAD) who are acceptable candidates for PTCA or stenting due to de novo, severely calcified coronary artery lesions.

Contraindications: The OAS is contraindicated when the VIPERWIRE guide wire cannot pass across the coronary lesion or the target lesion is within a bypass graft or stent. The OAS is contraindicated when the patient is not an appropriate candidate for bypass surgery, angioplasty, or atherectomy therapy, or has angiographic evidence of thrombus, or has only one open vessel, or has angiographic evidence of significant dissection at the treatment site and for women who are pregnant or children.

Warnings/Precautions:; Performing treatment in excessively tortuous vessels or bifurcations may result in vessel damage; The OAS was only evaluated in severely calcified lesions, A temporary pacing lead may be necessary when treating lesions in the right coronary and circumflex arteries; On-site surgical back-up should be included as a clinical consideration; Use in patients with an ejection fraction (EF) of less than 25% has not been evaluated. See the instructions for use before performing DIAMONDBACK 360 coronary orbital atherectomy procedures for detailed information regarding the procedure, indications, contraindications, warnings, precautions, and potential adverse events. For further information call CSI at 1-877-274-0901 and/or consult CSI’s website at www.csi360.com.

Caution: Federal law (USA) restricts this device to sale by or on the order of a physician.

Diamondback 360® and Stealth 360®Peripheral Atherectomy Systems

The Diamondback 360® and Stealth 360® PAD Systems are percutaneous orbital atherectomy systems indicated for use as therapy in patients with occlusive atherosclerotic disease in peripheral arteries and stenotic material from artificial arteriovenous dialysis fistulae. The Systems arecontraindicated 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. For further information call CSI at 1-877-274-0901 and/or consult CSI’s website at www.csi360.com.

Caution: Federal law (USA) restricts this device to sale by or on the order of a physician.

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Investor Contact:Jack Nielsen651-202-4919j.nielsen@csi360.com

©2017 Cardiovascular Systems, Inc.All Rights ReservedDiamondback 360 and CSI are registered trademarks of Cardiovascular Systems, Inc.www.csi360.com

NASDAQ: CSII