Risk factors for early and delayed post-operative bleeding after endoscopic submucosal dissection of gastric neoplasms, including patients with continued use of antithrombotic agents

BACKGROUND Endoscopic submucosal dissection (ESD) has become widely accepted as a standard treatment for gastric epithelial neoplasms. Antithrombotic agents are widely used to prevent thromboembolic disease. However, the feasibility of endoscopic procedures for patients using such agents has been rarely investigated. The aim of this study was to identify risk factors for post-operative bleeding after gastric ESD and to evaluate the relationship between the use of antithrombotic agents and post-operative bleeding. METHODS From June 2005 to March 2014, 413 patients with 425 gastric neoplasms were treated by ESD. The demographic and clinical parameters associated with post-operative bleeding were investigated. 83 patients receiving antithrombotic agents were separately assessed using various methods of administration during the ESD procedure. Post-operative bleeding that occurred within 5 days of ESD was defined as early post-operative bleeding, whereas subsequent bleeding was defined as delayed bleeding. RESULTS The overall post-operative bleeding rate was 4.7%. In patients with continued low-dose aspirin (LDA), heparin replacement (HR), or continued LDA along with HR, post-operative bleeding rates were 9.5%, 23.8%, and 25.0%, respectively. On multivariate analysis, a specimen size of ≥40 mm was a risk factor for early post-operative bleeding [odds ratio (OR) 6.08, 95% CI: 1.74-21.27], and HR and chronic kidney disease (CKD) requiring hemodialysis were risk factors for delayed bleeding (OR 12.23, 95% CI: 2.63-56.77 and OR 28.35, 95% CI: 4.67-172.11, respectively). Continued LDA was not a risk factor for post-operative bleeding. CONCLUSIONS Large specimen size is a risk factor for early post-operative bleeding, and HR and CKD requiring hemodialysis are risk factors for delayed bleeding. Patients with risk factors should be carefully watched, allowing for the timing of post-operative bleeding after ESD.