Objective: This study aims to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) after unfractionated heparin (UFH) bolus for the treatment of intermediate–high-risk pulmonary embolism. Materials and Methods: On the basis of initial treatment, 81 patients were divided into two groups: DOAC after UFH bolus infusion group (group D; n=32) and conventional therapy group (group C; n=49). The frequency of recurrence of venous thromboembolism (VTE) and bleeding within 6 months were compared. In addition, hospitalization length and thrombus reduction rate in the pulmonary artery on computed tomography (CT) at the chronic phase were assessed. Results: Recurrence of VTE was found in one (3.1%) and three patients (6.1%) (P=1.00) in groups D and C, respectively, whereas no bleeding events was found in group D and 8.2% of patients in group C (P=0.15). Group D showed shorter hospitalization (7.2±2.3 days) than group C (15.7±9.9 days; P<0.001). In the subset of patients with serial CT assessment (group D, n=20; group C, n=38), almost all thrombus of pulmonary artery were disappeared and the thrombus reduction rates were similar between the two groups (group D, 99.5%; group C, 97.1%; P=0.59). Conclusion: DOAC administration immediately after UFH bolus treatment has the same efficacy and safety, whereas hospitalization days were significantly shorter than the conventional treatment group.
Administration of Direct Oral Anticoagulant Immediately after Unfractionated Heparin Bolus for the Treatment of Intermediate–High-Risk Pulmonary Thromboembolism