Postendoscopic Submucosal Dissection Bleeding Risk of Periprocedural Aspirin Maintenance Therapy in Clopidogrel Users as Single or Dual Antiplatelet Agents

Background/Aims: Aspirin maintenance is recommended during endoscopic submucosal dissection (ESD) in patients with antiplatelet therapy (APT) who are at high-thromboembolic risk. We evaluated the post-ESD bleeding risk during aspirin maintenance therapy and the timing of clopidogrel resumption. Methods: Patients who underwent ESD for early gastric cancer or adenoma between 2011 and 2020 were included. Patients receiving APT who were at low thromboembolic risk stopped APT 7 days before ESD and resumed it 1 month after ESD (interrupted group). Patients receiving APT who were at high thromboembolic risk were maintained on aspirin (maintenance group), and pre-ESD clopidogrel users receiving one or two antiplatelet agents stopped clopidogrel 7 days before ESD and resumed it on day 15 after ESD. The primary outcome was post-ESD bleeding. Results: Of the 2,346 ESD cases, the overall post-ESD bleeding rate was 3.8% (90/2,346). The bleeding incidence was higher in the aspirin maintenance group (13.0%, 16/123) than in the interrupted group (2.9%, 6/209) and nonusers (3.4%, 68/2,014; p<0.001). The increase in bleeding rate was significant within 14 days, whereas it became insignificant ≥15 days after ESD. In the maintenance group, bleeding risk was not significantly increased in pre-ESD single clopidogrel users (hazard ratio [HR], 1.38; p=0.582) or dual APT users (HR, 1.18; p=0.797) compared with the single aspirin users. No bleeding events occurred after clopidogrel resumption on post-ESD day 15. Additionally, no thromboembolic events occurred in the maintenance or interrupted therapy groups. Conclusions: Periprocedural aspirin maintenance increased post-ESD bleeding within 2 weeks of gastric ESD. Resuming original clopidogrel therapy 2 weeks after ESD did not increase bleeding risk in patients receiving periprocedural aspirin maintenance therapy.