Use and Outcomes Associated with Bridging During Anticoagulation Interruptions in Patients with Atrial Fibrillation: Findings from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF)

Background —Temporary interruption of oral anticoagulation (OAC) for procedures is often required and some propose using bridging anticoagulation. However, the use and outcomes of bridging during OAC interruptions in clinical practice are unknown. Methods and Results —The ORBIT-AF registry is a prospective, observational registry study of US outpatients with AF. We recorded incident temporary interruptions of OAC for a procedure, including use and type of bridging therapy. Outcomes included multivariable-adjusted rates of myocardial infarction (MI), stroke or systemic embolism (SSE), major bleeding, cause-specific hospitalization, and death within 30 days. Of 7,372 patients treated with OAC, 2,803 overall interruption events occurred in 2,200 patients (30%) at median follow-up of 2 years. Bridging anticoagulants were used in 24% (n=665), predominantly with low-molecular weight heparin (73%, n=487) and unfractionated heparin (15%, n=97). Bridged patients more likely had prior cerebrovascular events (22% vs. 15%, p=0.0003) and mechanical valve replacements (9.6% vs. 2.4%, p<0.0001); however there was no difference in CHA2DS2-VASc scores (94% ≥2 vs. 95%, p=0.5). Bleeding events were more common in bridged patients than non-bridged (5.0% vs. 1.3%, adjusted OR 3.84, p<0.0001). Incidence of MI, SSE, major bleeding, hospitalization, or death within 30 days was also significantly more common in patients receiving bridging (13% vs. 6.3%, adjusted OR 1.94, p=0.0001). Conclusions —Bridging anticoagulation is used in one-quarter of anticoagulation interruptions and is associated with higher risk for bleeding and adverse events. These data do not support the use of routine bridging and additional data are needed to identify best practices around anticoagulation interruptions. Clinical Trial Registration Information —clinicaltrials.gov. Identifier: NCT01165710.