DES should not be used in primary PCI for patients with STEMI who are unable to tolerate or comply with a prolonged course of DAPT because of the increased risk of stent thrombosis with premature discontinua- tion of one or both agents.240 246 (Level of Evidence: B) Coronary stents are used routinely at the time of primary PCI. Compared with balloon angioplasty, BMS implantation during primary PCI decreases the risk for subsequent target-lesion and target-vessel revascularization and possibly the risk for rein- farction, but is not associated with a reduction in the mortal- Compared with BMS, DES implantation decreases restenosis rates and the need for reintervention but does not definitively reduce rates of death or reinfarction. Notably, DES in this setting does not increase the risk of early or late stent Controversy remains as to whether the risk of very late stent thrombosis is higher with first-generation DES than with BMS.249 The lowest rates of stent thrombosis have been reported with cobalt-chromium everolimus-eluting The greatest challenge in deciding the approach at the time of primary PCI, however, is determining emergently whether the patient is a candidate for a prolonged (ie, 1 year) course of DAPT. DES should be avoided in the presence of financial or social barriers that may limit patient compliance, elevated bleeding risk, the anticipated need for invasive or sur- gical procedures in the subsequent 1 year, or an independent indication for long-term anticoagulant therapy. 4.4. Adjunctive Antithrombotic Therapy for Primary PCI See Table 3 for a summary of recommendations from this sec- tion and Online Data Supplement 3 for additional information on antithrombotic therapy. 4.4.1. Antiplatelet Therapy to Support Primary PCI for STEMI: Recommendations Class I 1. 