Perioperative Bridging Therapy With Unfractionated Heparin or Low-Molecular-Weight Heparin in Patients With Mechanical Prosthetic Heart Valves on Long-Term Oral Anticoagulants (from the REGIMEN Registry)

Patients with mechanical prosthetic heart valves require long-term oral anticoagulant therapy (OAT). During the temporary interruption of OAT, bridging anticoagulant therapy with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) is recommended. This prespecified subgroup analysis from REGIMEN—a large, prospective, multicenter registry—compared UFH (n = 73) and LMWH (n = 172) as bridging anticoagulation in patients with mechanical heart valves on long-term OAT. Patient demographics and co-morbidities were generally similar between groups. There were more bileaflet valves in the LMWH group (67.4% vs 43.8%, p = 0.0005), but no differences in valve positions between groups. The LMWH group was less likely to undergo major surgery (33.7% vs 58.9%, p = 0.0002) and cardiothoracic surgery (7.6% vs 19.2%, p = 0.008), and to receive intraprocedural anticoagulants or thrombolytics (4.1% vs 13.7%, p = 0.007). Major adverse event rates (5.5% vs 10.3%, p = 0.23) and major bleeds (4.2% vs 8.8%, p = 0.17) were similar in the LMWH and UFH groups, respectively; 1 arterial thromboembolic event occurred in each group. More LMWH-bridged patients were treated as outpatients or discharged from the hospital in