Carotid Restenosis Following Endarterectomy in Patients Managed With Single Antiplatelet Therapy Versus Dual Antiplatelet Therapy

Background: Antiplatelet therapy is a cornerstone in the management of carotid artery disease following carotid endarterectomy (CEA). There is a paucity of data regarding the effect of dual antiplatelet therapy (DAPT) on restenosis rates. Methods: A retrospective review of patients who underwent CEA from January 1, 2007 to December 31, 2013 was performed at a single center. Study groups consisted of subjects who received DAPT and those who received single antiplatelet therapy (SAPT) following CEA. Restenosis was evaluated by carotid duplex. Severity and timing of restenosis, postoperative complications, and reinterventions were compared between study groups. Results: Between January 1, 2007 and December 31, 2013, 1453 patients underwent CEA. The SAPT group consisted of 245 patients and the DAPT group consisted of 1208 patients. No difference in restenosis was identified between groups at less than 6 weeks (6.5% vs. 11.7% 50-79% stenosis, 0% vs. 2.2% 80-99% stenosis, 2.2% vs. 0.6% occlusion, p = 0.368), and 6 weeks to 2 years (20.6% vs. 17.9% 50-79% stenosis, 1.1% vs. 1.0% 80-99% stenosis, 1.6% vs. 0.4% occlusion, p = 0.242). A higher rate of restenosis in SAPT was found greater than 2 years from surgery (68.4% vs. 82.4% 50% stenosis vs. 17.6% of the DAPT group (adjusted OR 0.48, 95% CI 0.30-0.76, p = 0.002). In a propensity matched-population, 32.7% of the SAPT group demonstrated restenosis vs. 13.7% of the DAPT group (adjusted OR 0.35, 95% CI 0.16-0.77, p = 0.009). There was no difference in the need for reintervention between study groups (DAPT 3.8% vs SAPT 3.3%, p = 0.684). Conclusion: Following CEA, patients on DAPT exhibited lower rates of late restenosis. Despite this finding, a clinical difference in reintervention was not found during this study period.