Perioperative Outcomes in Factor XI Deficiency: A Systematic Review

Background Congenital factor XI (FXI) deficiency has a variable bleeding phenotype, and FXI activity alone does not predict perioperative bleeding. Management practices remain heterogeneous, and available evidence derives from case reports, small case series, and retrospective cohorts. This systematic review evaluated perioperative bleeding outcomes and management strategies in FXI‐deficient patients undergoing surgical procedures. Methods We systematically searched five databases (2016–2024). Two reviewers independently screened studies, extracted data, and assessed methodological quality. Because of heterogeneity among studies, cohort data were synthesized qualitatively. Case reports were summarized descriptively, and an exploratory framework combining FXI category and fibrinolytic risk of the procedure was constructed to illustrate patterns in bleeding outcomes. Results Twenty‐one studies met inclusion criteria: four retrospective cohorts and seventeen case reports, describing more than 590 procedures. Cohort bleeding rates ranged from 0% to 19%, with major bleeding ≤ 7%. FXI activity showed no consistent association with perioperative bleeding. Procedural factors and personal bleeding history are more often aligned with outcomes. Most case reports involved severe FXI deficiency and used FFP‐based prophylaxis, often with antifibrinolytics. Bleeding events in case reports were infrequent. In the exploratory two‐dimensional visualization, bleeding appeared more common among patients with FXI ≤ 10 IU/dL undergoing high‐fibrinolytic procedures; however, event numbers were small and prophylaxis was widely used, limiting interpretation. Conclusions FXI levels alone appear insufficient to predict bleeding risk in FXI‐deficient patients. A multifactorial approach, integrating surgical risk and haemostatic strategy, may be required, and further study is needed to optimize preoperative management strategies for FXI‐deficient patients. Clinical trial registration Clinical trial registration was not applicable for this study.