Anticoagulants safe, effective in cirrhosis with portal vein thrombosis, review finds

Researchers analyzed eight studies with 353 patients to assess the effect of low-molecular-weight heparin or warfarin on recanalization, thrombosis progression, and bleeding.

In patients with cirrhosis and portal vein thrombosis, anticoagulant therapy was associated with increased recanalization, reduced thrombosis progression, and no increase in bleeding, a recent meta-analysis found.

Researchers included studies that assessed the effect of anticoagulant therapy, with either low-molecular-weight heparin or warfarin, on patients with cirrhosis and portal vein thrombosis. They included eight studies, with 353 patients, in their systematic review and meta-analysis. Only one was a randomized controlled trial and five of the eight studies were retrospective. The results were published online by Gastroenterology on May 4.

Overall, patients who were treated with anticoagulants were significantly more likely to undergo portal vein thrombosis recanalization (71% vs. 42%; P<0.0001). Six studies with 217 patients assessed whether patients had complete recanalization, and rates of this outcome were higher in patients receiving anticoagulants than in patients not on anticoagulants (53% vs. 33%; P=0.002). Using data from six studies with 225 patients, the reviewers also found that progression of thrombosis was less likely in patients on anticoagulants (9% vs. 33%; P<0.0001).

Six studies with 257 patients reported bleeding rates, which were similar overall between patients who did and did not receive anticoagulants. Four studies with 158 patients reported spontaneous variceal bleeding; this complication was significantly less common in patients taking anticoagulants (P=0.04). The study's results show that, for patients with cirrhosis and portal vein thrombosis, anticoagulants are useful for treatment of thrombosis and its sequelae and are not associated with increased bleeding risk, the study authors said.

They noted several limitations to the study, including the limited number of patients, lack of information regarding site and extension of thrombi, and inclusion of data mostly from nonrandomized trials. The analysis suggested that low-molecular-weight heparin and warfarin may have differing effects—heparin was associated with improvements in portal vein thrombosis resolution and progression, while warfarin only appeared to affect progression—but this finding would need to be confirmed by a randomized controlled trial, the authors also said.