Perioperative Antithrombotic Management in Major Vascular Surgery: A Narrative Review of Competing Thrombotic and Haemorrhagic Risks

Objective: To critically synthesize the available evidence on perioperative antithrombotic strategies across major vascular surgical procedures, with emphasis on study design, level of evidence, and clinical applicability, and to identify persistent evidence gaps. Methods: A narrative review of the literature was performed, focusing on randomized controlled trials, large observational studies, and major registry datasets evaluating perioperative antithrombotic strategies in vascular surgery. Evidence was stratified according to procedure type, data source, and geographic origin. Results: The evidence base is overwhelmingly observational, with predominant reliance on North American registry data, particularly the Vascular Quality Initiative (VQI). No procedure-specific randomized controlled trial has directly evaluated perioperative antithrombotic strategies in major vascular surgery. Carotid endarterectomy (CEA) remains the most extensively studied procedure, although the effect of dual antiplatelet therapy (DAPT) on ischaemic outcomes is inconsistent across large datasets (e.g., VQI RR 0.80 in 125,469 patients; pooled international analyses OR 0.87 in 47,411 patients), while an increased bleeding risk is consistently reported across studies. For infrageniculate prosthetic bypass, observational data suggest a potential association between direct oral anticoagulants and improved outcomes compared with warfarin; however, this signal lacks randomized or externally validated confirmation. The WAVE trial, the only large randomized study in peripheral arterial disease evaluating antithrombotic intensification, demonstrated increased bleeding without reduction in major cardiovascular events. Across vascular procedures, no randomized evidence supports routine escalation of perioperative antithrombotic therapy. Conclusion: Current evidence does not support definitive, procedure-specific recommendations for perioperative antithrombotic management in vascular surgery and should be considered hypothesis-generating. The absence of randomized, procedure-targeted trials represents a major limitation in the field. Future research should prioritize high-quality prospective studies to better define risk-benefit balance, particularly in high-risk procedures such as major amputation. A structured framework incorporating thrombotic risk, bleeding risk, and procedural factors may support individualized decision-making but requires formal validation.