X0306 4 2022-08-12 0001180145 Cardiovascular Systems Inc CSII 0001781460 Hastings John M. 1225 OLD HIGHWAY 8 NW ST. PAUL MN 55112 1 VP Manufacturing & Operations Common Stock 2022-08-12 4 F 0 1628 16.64 D 53652 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. /s/ Andrew Nick as Attorney-in-Fact for John M. Hastings pursuant to Power of Attorney previously filed. 2022-08-16