Anticoagulation for the treatment of portal vein thrombosis in liver cirrhosis: a systematic review and meta-analysis of observational studies.

BACKGROUND & AIMS Systematic review and meta-analysis were performed to evaluate the safety and efficacy of anticoagulation for the treatment of portal vein thrombosis (PVT) in cirrhotic patients. METHODS The PubMed, EMBASE, Cochrane Library, and ScienceDirect databases were searched. The rates of bleeding complications and portal vein recanalization in patients who received anticoagulant therapy were pooled. The odds ratio (OR) with 95% confidence interval (CI) was calculated to express the difference in the rate of portal vein recanalization between anticoagulation and non-anticoagulation groups. All meta-analyses were conducted by using a random-effects model. RESULTS Sixteen of 960 initially identified papers were included. Two studies reported a low incidence of major anticoagulation-related complications (4% [2/55] and 3% [1/33]), but no lethal complications occurred. The rate of anticoagulation-related bleeding ranged from 0% to 18% with a pooled rate of 3.3% (95% CI=1.1%-6.7%). The heterogeneity was not significant in the meta-analysis. The total rate of portal vein recanalization ranged from 37% to 93% with a pooled rate of 66.6% (95% CI=54.7%-77.6%). The rate of complete portal vein recanalization ranged from 0% to 75% with a pooled rate of 41.5% (95% CI=29.2%-54.5%). However, the heterogeneity was significant in the 2 meta-analyses. The rate of complete portal vein recanalization was significantly higher in anticoagulation group than in non-anticoagulation group (OR=4.16, 95% CI=1.88-9.20, P=0.0004). The heterogeneity was not significant in the meta-analysis. CONCLUSION Anticoagulation could achieve a relatively high rate of portal vein recanalization in cirrhotic patients with PVT. Given that only a small number of non-randomized comparative studies are reported, randomized controlled trials are warranted to confirm the risk-to-benefit of anticoagulation in such patients, especially anticoagulation-related bleeding.