Periprocedural heparin bridging in patients receiving vitamin K antagonists: systematic review and meta-analysis of bleeding and thromboembolic rates.

BACKGROUND: Periprocedural bridging with unfractionated heparin or low-molecular-weight heparin aims to reduce the risk of thromboembolic events in patients receiving long-term vitamin K antagonists. Optimal periprocedural anticoagulation has not been established.

METHODS AND RESULTS: MEDLINE, EMBASE, and Cochrane databases (2001-2010) were searched for English-language studies including patients receiving heparin bridging during interruption of vitamin K antagonists for elective procedures. Data were independently collected by 2 investigators (κ=0.90). The final review included 34 studies with 1 randomized trial. Thromboembolic events occurred in 73 of 7118 bridged patients (pooled incidence, 0.9%; 95% confidence interval [CI], 0.0.0-3.4) and 32 of 5160 nonbridged patients (pooled incidence, 0.6%; 95% CI, 0.0-1.2). There was no difference in the risk of thromboembolic events in 8 studies comparing bridged and nonbridged groups (odds ratio, 0.80; 95% CI, 0.42-1.54). Bridging was associated with an increased risk of overall bleeding in 13 studies (odds ratio, 5.40; 95% CI, 3.00-9.74) and major bleeding in 5 studies (odds ratio, 3.60; 95% CI, 1.52-8.50) comparing bridged and nonbridged patients. There was no difference in thromboembolic events (odds ratio, 0.30; 95% CI, 0.04-2.09) but an increased risk of overall bleeding (odds ratio, 2.28; 95% CI, 1.27-4.08) with full versus prophylactic/intermediate-dose low-molecular-weight heparin bridging. Low-thromboembolic-risk and/or non-vitamin K antagonist patient groups were used for comparison. Study quality was poor with heterogeneity for some analyses.

CONCLUSIONS: Vitamin K antagonist-treated patients receiving periprocedural heparin bridging appear to be at increased risk of overall and major bleeding and at similar risk of thromboembolic events compared to nonbridged patients. Randomized trials are needed to define the role of periprocedural heparin bridging.