Efficacy of Direct Oral Anticoagulants Vs Warfarin Vs Low Molecular Weight Heparin in the Treatment of Acute Splanchnic Vein Thrombosis in Patients with Underlying Myeloproliferative Disorder

Abstract

Introduction: Myeloproliferative neoplasms (MPNs) are hematopoietic stem cell disorders characterized by clonal proliferation of myeloid-lineage cells. Venous thrombosis poses a significant morbidity risk for MPN patients. The current recommended treatments for acute splanchnic vein thrombosis (SVT) are warfarin and low molecular weight heparin (LMWH). Direct oral anticoagulants (DOACs) are potential alternatives due to their predictable dose response and oral administration, but limited data exists for their use in acute SVTs. This retrospective study aims to assess the efficacy and outcomes of DOACs, LMWH, and warfarin in treating acute SVTs in patients with underlying MPN. Methods: We included patients of all ages with underlying myeloproliferative neoplasms and splanchnic vein thrombosis, with no underlying liver diseases, from Henry Ford Hospital Clinics in metropolitan Detroit, Michigan between 2013 and 2023. Patient data, which included age, gender, race, and BMI were recorded. The primary outcome was complete radiographic resolution (CRR) of the SVT, and secondary outcomes included recanalization, thrombosis progression, recurrent thrombosis, major bleeding, thrombocytopenia, and skin necrosis. The outcomes were compared between the three anticoagulant groups and patients using aspirin. Results: Among the 34 MPN patients with SVT, warfarin was prescribed most frequently (n=19), followed by enoxaparin (n=5) and DOACs (n=5). Although no significant differences were observed, warfarin showed the highest CRR rates (41.2%), while enoxaparin and DOACs had equal CRR rates (25%). DOACs showed recanalization rates similar to warfarin and higher than enoxaparin (44.4% and 47.1% vs. 20.0%, respectively). LMWH was associated with increased recurrent thrombosis rates (50.0%), while DOACs had a higher risk of major bleeding. All three anticoagulants had similar effects on thrombocytopenia and SVT progression. Aspirin use was linked to a higher risk of major bleeding (42.9%), but not using aspirin correlated with complete SVT resolution (30.8%), SVT progression (20.8%), recurrent thrombosis (29.2%), and thrombocytopenia (28.6%). Conclusions: Although limited by a small sample size, our study found no significant differences among the three anticoagulant groups. This contributes to establishing the role of DOACs in treating SVTs in patients with underlying MPN. Further studies with larger sample sizes are needed to explore the efficacy of DOACs compared to warfarin. Additionally, investigating the potential benefits of early thrombolysis in conjunction with anticoagulation for SVT patients with underlying MPN should be pursued, as the rates of complete resolution in these patients were low.