What is the approach to anticoagulation (anti-clotting medication) bridging in patients with atrial fibrillation (AFib) undergoing surgery?

Anticoagulation Bridging in Patients with Atrial Fibrillation Undergoing Surgery

For most patients with atrial fibrillation without mechanical heart valves who require interruption of warfarin for procedures, bridging anticoagulation therapy is not recommended as it increases bleeding risk without reducing thromboembolic events. 1, 2

Risk Stratification Approach

Patients Who DO NOT Require Bridging

• Patients with nonvalvular atrial fibrillation at low to moderate thromboembolic risk (CHA₂DS₂-VASc score <7 or CHADS₂ score <5) should undergo perioperative management without bridging therapy 2, 1
• For these patients, simply stopping warfarin 5 days before the procedure and resuming it after adequate hemostasis has been achieved is sufficient 2
• This approach is supported by the BRIDGE trial, which demonstrated that no bridging was noninferior to bridging with LMWH for prevention of arterial thromboembolism (0.4% vs 0.3%) but significantly reduced major bleeding (1.3% vs 3.2%) 1, 2

Patients Who DO Require Bridging

• Bridging therapy with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) is recommended for patients with:
  • Mechanical heart valves 2
  • Recent stroke or TIA (<3 months) 2
  • Very high thromboembolic risk (CHA₂DS₂-VASc score ≥7 or CHADS₂ score of 5-6) 2
  • History of perioperative stroke 2

Management Protocol for Warfarin Interruption

Preoperative Management

• For patients NOT requiring bridging:

  • Stop warfarin 5 days before elective procedure 2
  • Check INR the day before surgery; proceed if INR ≤1.5 2
  • No heparin bridging needed 2, 1

• For patients requiring bridging:

  • Stop warfarin 5 days before procedure 2
  • Start therapeutic-dose UFH or LMWH (e.g., dalteparin 100 IU/kg twice daily) 3 days before procedure 1, 2
  • Administer last dose of LMWH 24 hours before procedure (use half-dose or skip last dose) 1
  • For UFH, stop infusion 4-6 hours before procedure 2

Postoperative Management

• For patients NOT requiring bridging:

  • Resume warfarin within 24 hours after procedure when adequate hemostasis is achieved 2
  • No postoperative heparin needed 1, 2

• For patients requiring bridging:

  • Resume warfarin within 24 hours after procedure when adequate hemostasis is achieved 2
  • Resume therapeutic-dose UFH or LMWH 24-72 hours after procedure, depending on bleeding risk 2, 1
  • Continue bridging until INR reaches therapeutic range (≥2.0) 2

Special Considerations

Direct Oral Anticoagulants (DOACs)

• For patients on DOACs (apixaban, rivaroxaban, dabigatran, edoxaban):
  • Generally, no bridging is required when interrupting DOACs 2, 3
  • Timing of interruption depends on renal function and procedure bleeding risk 3
  • For apixaban: discontinue at least 48 hours prior to procedures with moderate/high bleeding risk and 24 hours prior to procedures with low bleeding risk 3
  • Resume DOACs as soon as adequate hemostasis is established 3

Procedures with Low Bleeding Risk

• For minor procedures with low bleeding risk (dental extractions, minor skin procedures):
  • Consider performing without interruption of oral anticoagulation 2
  • For warfarin, target lower INR range if possible 2

Common Pitfalls and Caveats

• Overuse of bridging therapy: Bridging increases bleeding risk without reducing thromboembolic events in most patients with AF 1, 4
• Inadequate risk assessment: Failure to properly stratify patients based on thromboembolic risk can lead to inappropriate bridging decisions 2
• Delayed resumption of anticoagulation: Delaying anticoagulation resumption unnecessarily increases thromboembolic risk 2
• Inappropriate DOAC management: DOACs have shorter half-lives than warfarin and generally don't require bridging 3
• Failure to consider procedure bleeding risk: The timing of anticoagulation interruption should account for the bleeding risk of the specific procedure 2

By following this evidence-based approach to perioperative anticoagulation management in patients with atrial fibrillation, clinicians can minimize both thromboembolic and bleeding complications while ensuring optimal patient outcomes.