X0306 4 2023-02-12 0001180145 Cardiovascular Systems Inc CSII 0001174531 Ward Scott R. 1225 OLD HIGHWAY 8 NW ST. PAUL MN 55112 1 1 0 0 Chairman and CEO Common Stock 2023-02-12 4 F 0 1493 19.70 D 805945 D Common Stock 2023-02-13 4 A 0 5077 0 A 811022 D Restricted Stock Units Common Stock 34297 34297 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. Restrictions lapse as to 2,539 shares on 2/14/24 and as to 2,538 shares on 2/14/25. /s/ Andrew Nick as Attorney-in-Fact for Scott R. Ward pursuant to Power of Attorney previously filed. 2023-02-14