Bemiparin Versus Unfractionated Heparin as Bridging Therapy in the Perioperative Management of Patients on Vitamin K Antagonists: The BERTA Study Amparo SantamariaArantxa UgarrizaCarmen MunozIsabel De DiegoFrancisca Lopez-Chulia • Carmen BenetJavier Martinez-GonzalezNatividad GomezElena PinaXavier Ortin • Pascual MarcoFranciso Javier RoncalesJordi Fontcuberta

Background and Objective The management of patients on vitamin K antagonist therapy who require an invasive procedure is problematic. A randomised, controlled, double-blind clinical trial was designed to compare the efficacy and safety of bemiparin, a low molecular weight heparin (LMWH), with unfractionated heparin (UFH) as bridging therapy: the BERTA (BEmiparin Randomised Trial on bridging Anticoagulants) study. Methods Two hundred and six patients on long-term oral anticoagulation therapy (OAT) requiring an invasive procedure were randomized to receive bridging therapy with bemiparin ? matching placebo or UFH. OAT was resumed on day 1. The study medication was continued for 5‐6 days after the procedure. The primary efficacy endpoint was the combined incidence of arterial and venous thromboembolic events. The primary safety endpoint was the incidence of major bleeding within 10 days after the invasive procedure. Results There were no thromboembolic events in the bemiparin group, but two events (2.2 %) occurred in the UFH group. No major bleeding occurred in either group, but minor bleeding occurred in four patients (4.3 %) and six patients (6.1 %) in the bemiparin and UHF groups, respectively. No deaths and no cases of severe thrombocytopenia occurred during the whole study period. Trial registration: ClinicalTrials.gov identifier: NTC 00484822.