Comparison of safety of subcutaneous enoxaparin as outpatient anticoagulation bridging therapy in patients with a mechanical heart valve versus patients with nonvalvular atrial fibrillation.

Patients with mechanical heart valves (MHVs) are at a higher risk for thromboembolic events than patients with atrial fibrillation (AF). This difference is observed in the higher maintenance international normalized ratio (INR) range for patients with MHV and in the selection for anticoagulation bridge therapy when warfarin is interrupted perioperatively. However, once the decision is made to "bridge," the same therapeutic options, unfractionated heparin and subcutaneous low-molecular-weight heparin (LMWH), are applicable to the 2 patient populations.