FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN 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 * Thatcher Robert J   2. Issuer Name and Ticker or Trading Symbol CARDIOVASCULAR SYSTEMS INC [NONE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Executive VP (Last) (First) (Middle) 651 CAMPUS DRIVE 3. Date of Earliest Transaction (Month/Day/Year) 02/25/2009 (Street) ST. PAUL, MN 55112 4. If Amendment, Date Original Filed(Month/Day/Year) 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 Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 02/25/2009   C   12,378 A (1) 12,378 D   Common Stock 02/25/2009   D   12,378 D (2) 0 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Underlying Securities (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A-1 Conv Preferred Stock	(3)	02/25/2009		C			12,378	(4)	(4)	Common Stock	12,378	$ 0	0	D
Stock Option (right to buy)	(5)	02/25/2009		D			100,000	(5)	(5)	Common Stock	100,000	$ 0	0	D
Stock Option (right to buy)	(5)	02/25/2009		D			12,000	(5)	(5)	Common Stock	12,000	$ 0	0	D
Stock Option (right to buy)	(5)	02/25/2009		D			46,000	(5)	(5)	Common Stock	46,000	$ 0	0	D
Stock Option (right to buy)	(5)	02/25/2009		D			35,000	(5)	(5)	Common Stock	35,000	$ 0	0	D
Stock Option (right to buy)	(5)	02/25/2009		D			50,000	(5)	(5)	Common Stock	50,000	$ 0	0	D
Warrant	(6)	02/25/2009		D			4,707	(6)	(6)	Common Stock	4,707	$ 0	0	D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Thatcher Robert J 651 CAMPUS DRIVE ST. PAUL, MN 55112			Executive VP

Signatures

/s/ Carlye S. Landin as Attorney-in-Fact for Robert J. Thatcher pursuant to Power of Attorney previously filed.		02/27/2009
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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)	Immediately prior to the consummation of the merger between the issuer and Replidyne, Inc., each share of Series A-1 convertible preferred stock was converted into approximately 1.032 shares of the issuer's common stock.
(2)	Disposed of pursuant to a merger agreement among the issuer, Responder Merger Sub, Inc. and Replidyne, Inc. (now known as "Cardiovascular Systems, Inc."), pursuant to which each share of the issuer's common stock was converted into 0.647 shares of common stock of Replidyne, Inc.
(3)	Immediately prior to the consummation of the merger between the issuer and Replidyne, Inc., each share of Series A-1 convertible preferred stock was converted into approximately 1.032 shares of the issuer's common stock.
(4)	Each share of Series A-1 convertible preferred stock was convertible at any time, at the holder's election, into 1.032 shares of common stock and had no expiration date.
(5)	Disposed of pursuant to a merger agreement among the issuer, Responder Merger Sub, Inc. and Replidyne, Inc. (now known as "Cardiovascular Systems, Inc."), pursuant to which each of the issuer's stock options was assumed by Replidyne, Inc. and became exercisable to purchase shares of Replidyne, Inc. common stock; each share covered by the issuer's options was converted into 0.647 shares of common stock of Replidyne, Inc., and the exercise price of each option was adjusted by dividing the pre-merger exercise price by 0.647 and rounding up to the nearest cent.
(6)	Disposed of pursuant to a merger agreement among the issuer, Responder Merger Sub, Inc. and Replidyne, Inc. (now known as "Cardiovascular Systems, Inc."), pursuant to which each of the issuer's common stock warrants was assumed by Replidyne, Inc. and became exercisable to purchase shares of Replidyne, Inc. common stock; each share covered by the issuer's common stock warrants was converted into 0.647 shares of common stock of Replidyne, Inc., and the exercise price of each warrant was adjusted by dividing the pre-merger exercise price by 0.647 and rounding up to the nearest cent.

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