Impact of Antithrombotic Therapy on Thrombotic and Bleeding Complications after Elective Endovascular Repair of Abdominal Aortic Aneurysms.

PURPOSE

To investigate the influence of antithrombotic therapy on occurrence of thrombotic and bleeding complications after endovascular aneurysm repair (EVAR).

METHODS

In this retrospective single-center cohort study, patients who underwent elective endovascular aneurysm repair for abdominal aortic aneurysm were categorized into three antithrombotic groups: single antiplatelet therapy (SAPT), anticoagulants, or dual antiplatelet therapy (DAPT). Outcome measures were the incidence of major adverse cardiovascular events (MACE), prosthetic limb occlusions, and bleeding complications during follow-up.

RESULTS

Among 616 patients (SAPT: n = 450, anticoagulants: n = 84, and DAPT: n = 82), Kaplan-Meier analysis showed no significant difference (log-rank p = 0.37) in incidence of MACE between patients receiving SAPT (20.9%), anticoagulants (25.0%), and DAPT (14.6%) during a median follow-up of almost 4 years. In multivariable Cox regression analysis, only age (HR = 1.03; 95% CI 1.01-1.06, p = 0.01) and American Society of Anesthesiologists (ASA) classification (HR = 1.46; 95% CI 1.12-1.91; p = 0.01) were significant predictors for MACE. Prosthetic limb occlusion was observed in 38 patients during a median follow-up of 4 years; incidence between patients receiving SAPT (5.8%), anticoagulants (10.7%), and DAPT (3.7%) was not significantly different (log-rank p = 0.08). Age (HR = 0.96; 95% CI 0.92-1.00; p = 0.03) and use of anticoagulants (HR = 3.79, 95% CI 1.46-9.83; p < 0.01) were significant predictors for prosthetic limb occlusion. Bleeding complications occurred in 73 patients during median follow-up of almost 4 years, without significant difference (log rank p = 0.06) in incidence between patients receiving SAPT (10.7%), anticoagulants (19.0%), and DAPT (11.0%). ASA classification (HR = 1.74; 95% CI 1.23-2.46; p < 0.01) was a significant predictor for bleeding complications.

CONCLUSION

Use of anticoagulants after EVAR appears to be associated with a higher risk of prosthetic limb occlusion compared to the use of single or dual antiplatelet therapy.