X0306 4 2022-08-12 0001180145 Cardiovascular Systems Inc CSII 0001818614 Rempe Stephen J. 1225 OLD HIGHWAY 8 NW ST. PAUL MN 55112 1 Chief Human Resources Officer Common Stock 2022-08-12 4 F 0 2005 16.64 D 85576 D The reporting person has elected to satisfy his tax withholding obligation in connection with the vesting of prior restricted stock grants by directing the Company to withhold shares otherwise issuable upon vesting of the previously reported grants. Includes 226 shares acquired on 6/30/22 pursuant to the Company's Employee Stock Purchase Plan. /s/ Andrew Nick as Attorney-in-Fact for Stephen J. Rempe pursuant to Power of Attorney previously filed. 2022-08-16