Experience With Dabigatran on Rate of Portal Vein Thrombosis Recanalization, Disease Progression and Survival

We assessed clinical, procoagulant and genetic risk factors and clinical outcomes in dabigatran-treated patients with non-tumoural acute and acute-on-chronic portal vein thrombosis (PVT). Patients with a new diagnosis of non-tumoural acute and acute-on-chronic PVT between January 2021 and January 2024 (aged ≥ 18 years) in those without/with cirrhosis (Child-Pugh (CP)-A/B/C ≤ 10) were started on dabigatran and followed and compared with those on vitamin K antagonist (VKA) and untreated individuals. Dabigatran was prescribed in 119 patients with PVT type 1 (61, 51.3%), type 2 (34, 28.6%), type 3 (24, 20.2%); 72 (60.5%) with cirrhosis [CP-A (27, 37.5%), CP-B (43, 59.7%) and CP-C10 (2, 2.8%)]. Procoagulant factors noted were JAK2V617F (10.1%), CALR (2.5%) and factor V Leiden (1.6%) mutations, antiphospholipid syndrome (APS, 15.2%), isolated Protein C (14.3%) and Protein S (16.8%) deficiency. 28 patients who declined anticoagulation/were unable to come for follow-up, and six with CP-C received VKA. Overall recanalization rate (RR) on dabigatran was 56 (47.1%); 25 (21%) complete recanalization, 31 (26%) partial recanalization and 63 (52.9%) stable PVT over median follow-up of 32 months. Patients not anticoagulated had a spontaneous RR in 21.4% (28 patients; p = 0.005 compared with dabigatran group) and none recanalized on VKA. On multivariable analysis, predictors of recanalization on dabigatran were Factor VIII Antigen level (FVIII:Ag, HR 0.6; 95% CI 0.3-0.9, p = 0.032), non-occlusive PVT (HR 3.5, 95% CI 1.9-5.6, p = 0.025) and acute PVT (HR 2.1; 95% CI 1.5-3.2, p = 0.003). Mortality was 14 (11.8%). On dabigatran, 47% of 119 patients achieved portal vein recanalization over 32 months of follow-up which was higher than the spontaneous RR (21.4%) in an untreated cohort. High Factor VIII:Ag was a predictor of non-recanalization. Dabigatran was safe in cirrhosis (CP-A and B) while further work is needed in CP-C.