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 *   Blackey Brent G 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) __X__ Director _____ 10% Owner _____ Officer (give title below) __X__ Other (specify below) Mbr of 13(d) grp owng > 10% 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)

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
Series A-1 Conv Preferred Stock	  (1)	  (1)	Common Stock	6,086	$ (1)	D	Â
Series B Conv Preferred Stock	  (2)	  (2)	Common Stock	5,049	$ (2)	D	Â
Stock Option (right to buy)	  (3)	10/08/2017	Common Stock	60,000	$ 5.11	D	Â
Stock Option (right to buy)	10/09/2007	10/08/2017	Common Stock	10,000	$ 5.11	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Blackey Brent G 651 CAMPUS DRIVE ST. PAUL, MN 55112	  X	Â	Â	Mbr of 13(d) grp owng > 10%

Signatures

/s/ Carlye S. Landin as Attorney-in-Fact for Brent G. Blackey 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)	Each share of Series A -1 convertible preferred stock is convertible at any time, at the holder's election, into 1.03 shares of common stock and has no expiration date.
(2)	Each share of Series B convertible preferred stock is convertible at any time, at the holder's election, into 1.01 shares of common stock and has no expiration date.
(3)	Exercisable in three equal increments of 20,000 on each of 10/9/08, 10/9/09 and 10/9/10.

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