Thrombosis Stent thrombosis causes complete blockage and may occur at any time: Acutely (immediately during or after the procedure) Subacutely (within 30 days) Late (> 30 days) Stent thrombosis may be due to inadequate stent expansion or apposition at the time of the procedure, discontinuation of dual antiplatelet therapy (eg, due to nonadherence, need for noncardiac surgery), or both.