Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Martin David
2. Date of Event Requiring Statement (Month/Day/Year)
12/29/2008
3. Issuer Name and Ticker or Trading Symbol
CARDIOVASCULAR SYSTEMS INC [CSII]
(Last)
(First)
(Middle)
651 CAMPUS DRIVE
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President and CEO
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

ST. PAUL, MN 55112
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 76,000
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (right to buy)   (1) 07/16/2011 Common Stock 110,000 $ 5.71 D  
Stock Option (right to buy)   (2) 08/14/2011 Common Stock 60,000 $ 5.71 D  
Stock Option (right to buy)   (3) 02/14/2012 Common Stock 540,000 $ 5.71 D  
Stock Option (right to buy)   (4) 06/11/2017 Common Stock 140,000 $ 5.11 D  
Stock Option (right to buy)   (5) 12/11/2017 Common Stock 375,000 $ 7.86 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Martin David
651 CAMPUS DRIVE
ST. PAUL, MN 55112
      President and CEO  

Signatures

/s/ Carlye S. Landin as Attorney-in-Fact for David L. Martin pursuant to Power of Attorney filed herewith. 12/29/2008
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Exercisable: 5,000 each month beginning 8/17/06.
(2) Exercisable in three equal installments of 20,000 on 8/15/07, 8/15/08 and 8/15/09.
(3) Exercisable: 15,000 each month beginning 3/15/07.
(4) Exercisable: 46,667 on 6/12/08 and 6/12/09 and 46,666 on 6/12/10.
(5) Exercisable: 187,500 on the first anniversary of the closing of the Company's merger with Replidyne, Inc. and 187,500 on the second anniversary of the merger.

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