P2Y12 inhibitor monotherapy is associated with superior outcomes as compared with aspirin monotherapy in chronic limb-threatening ischemia.

OBJECTIVE: Antiplatelet therapy is recommended in patients with peripheral arterial disease to reduce cardiovascular risk and improve outcomes. However, issues including the drug of choice and use of dual antiplatelet therapy (DAPT) vs monotherapy remain unclear. This study aims to compare the impact of aspirin (ASA) monotherapy, P2Y12 monotherapy, and DAPT on limb salvage (LS), amputation-free survival (AFS), and overall survival (OS) in patients undergoing lower extremity peripheral endovascular intervention (PVI) for chronic limb-threatening ischemia (CLTI). METHODS: The Vascular Quality Initiative PVI registry was used to identify index procedures completed for CLTI between March 1, 2010 and September 30, 2017. Patients were categorized by antiplatelet use at the time of last follow-up. Patients not on antiplatelet therapy were compared with ASA, P2Y12 monotherapy, and DAPT. Propensity score-matched samples were created for direct ASA vs P2Y12 and P2Y12 vs DAPT comparisons; veracity was confirmed by χ2 and Hosmer-Lemeshow tests. Kaplan-Meier and Cox regression were performed for OS, AFS, and LS. RESULTS: A total of 12,433 index PVI were completed for CLTI in 11,503 subjects in the pre-matched sample. Antiplatelet use at follow-up was: 12% none, 31% ASA, 14% P2Y12, and 43% DAPT. Median follow-up was 1389 days. P2Y12 monotherapy was associated with improved outcomes as compared with ASA monotherapy, OS (87.8% vs 85.5%l P = .026; Cox hazard ratio [HR], 0.82; 95% confidence interval [CI], 0.68-0.98; P = .03), AFS (79.6% vs 74.8%; P < .001; Cox HR, 0.75; 95% CI, 0.65-0.86; P < .001) and LS (89.5% vs 86.8%; P = .013; Cox HR, 0.74; 95% CI, 0.60-0.91; P = .004). P2Y12 monotherapy and DAPT had comparable OS (87.8% vs 88.9%; P = .62; Cox HR, 0.94; 95% CI, 0.77-1.14; P = .50), AFS (79.6% vs 81.5%; P = .33; Cox HR, 0.92; 95% CI, 0.78-1.07; P = .28), and LS (91.7% vs 89.4; P = .03; Cox HR, 0.80; 95% CI, 0.64-1.00; P = .06). CONCLUSIONS: P2Y12 monotherapy was associated with superior OS, AFS, and LS as compared with ASA monotherapy, and comparable OS, LS, and AFS with DAPT in patients undergoing PVI for CLTI. P2Y12 monotherapy may be considered over ASA monotherapy and DAPT in patients with CLTI, especially in patients with high bleeding risk.