Prognostic value of factor VIII, D-dimer and high molecular risk variants assessing re-thrombosis risk in non-cirrhotic portal vein thrombosis

BACKGROUND & AIMS: Patients with non-cirrhotic non-tumoral portal venous system thrombosis (NCNT-PVT) require long-term anticoagulation to prevent rethrombosis (either splanchnic or at any site, referred to as overall rethrombosis - oRT) when there is an underlying high-risk thrombophilic disorder or history of previous thrombotic episodes. However, up to 25% of patients without such indications still develop oRT. Elevated factor VIII (≥150%), D-dimer (≥500 ng/ml) or the presence of high molecular risk (HMR) variants have been proposed as risk predictors for oRT in these patients. This study aimed to compare the prognostic value of these three biomarkers in a cohort of patients with NCNT-PVT. METHODS: We performed a multicenter, retrospective, observational study including 123 patients with NCNT-PVT without an indication for long-term anticoagulation. RESULTS: During a median follow-up of 89.3 months (IQR 36-129), 33 patients (27%) developed venous oRT, with a cumulative incidence of 7%, 17% and 26% at 1, 5 and 10 years. Factor VIII ≥150% and HMR were associated with oRT risk (hazard ratio 5.92, 95% CI 2.67-13.15, p