<SEC-DOCUMENT>0001180145-19-000017-index.html : 20190531
<SEC-HEADER>0001180145-19-000017.hdr.sgml : 20190531
<ACCEPTANCE-DATETIME>20190531120525
ACCESSION NUMBER:		0001180145-19-000017
CONFORMED SUBMISSION TYPE:	SD
PUBLIC DOCUMENT COUNT:		2
<RULE>
<RULE-NAME>13p-1
<ITEM>
<ITEM-NUMBER>1.01
<ITEM-PERIOD>20181231
</ITEM>
<ITEM>
<ITEM-NUMBER>1.02
<ITEM-PERIOD>20181231
</ITEM>
</RULE>
FILED AS OF DATE:		20190531
DATE AS OF CHANGE:		20190531

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Cardiovascular Systems Inc
		CENTRAL INDEX KEY:			0001180145
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				411698056
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	FILING VALUES:
		FORM TYPE:		SD
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-52082
		FILM NUMBER:		19869368

	BUSINESS ADDRESS:	
		STREET 1:		1225 OLD HWY 8 NW
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55112
		BUSINESS PHONE:		651-259-1600

	MAIL ADDRESS:	
		STREET 1:		1225 OLD HWY 8 NW
		CITY:			ST. PAUL
		STATE:			MN
		ZIP:			55112

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	REPLIDYNE INC
		DATE OF NAME CHANGE:	20020813
</SEC-HEADER>
<DOCUMENT>
<TYPE>SD
<SEQUENCE>1
<FILENAME>formsd-2018.htm
<DESCRIPTION>SD2018
<TEXT>
Document 1 - file: formsd-2018.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-1.01
<SEQUENCE>2
<FILENAME>ex101conflictmineralsrepor.htm
<DESCRIPTION>EXHIBIT 1.01
<TEXT>
Document 2 - file: ex101conflictmineralsrepor.htm

</DOCUMENT>
</SEC-DOCUMENT>