Gastrointestinal bleeding risk in cirrhotic portal vein thrombosis: focus on thrombus extension to superior mesenteric vein

Background & aims Portal vein thrombosis (PVT) is a prevalent cirrhosis complication linked to gastrointestinal bleeding. This study aims to assess correlations between PVT classification and the risk of bleeding in patients with cirrhotic PVT. Methods This retrospective study included 380 hospitalized cirrhotic patients complicated by PVT, categorized into bleeding and non-bleeding groups based on history of gastrointestinal bleeding. Patients were followed for 12 months to calculate bleeding and recurrence rates. PVT was classified as non-extending or extending, based on the anatomical location and extent. Multivariate logistic regression analyses and propensity score matching (PSM) were used to evaluate the impact of superior mesenteric vein thrombosis (SMVT) extension on bleeding outcomes. Results Of 380 patients, 223 (58.7%) were in the bleeding group and 157 (41.3%) in the non-bleeding group; 267 (70.3%) had non-extending PVT and 113 (29.7%) extending PVT (89 involving SMV). During follow-up, 201 (55.5%) experienced bleeding, with a 63.7% recurrence rate in the initial bleeding group. Extended PVT and SMVT-positive patients were significantly more likely to have higher baseline bleeding rates, 12-month bleeding rates, and recurrence rates compared with non-extended and SMVT-negative patients (all P < 0.05). Multivariate analysis identified SMVT extension as an independent risk factor associated with baseline (OR = 2.194; P = 0.010) and 12-month bleeding (OR = 1.962; P = 0.018). PSM confirmed significant associations between SMVT extension and gastrointestinal bleeding at baseline ( P = 0.035) and 12 months ( P = 0.033). Conclusions In patients with cirrhosis and PVT, the extension into the SMV is significantly associated with an increased risk of gastrointestinal bleeding.