Safety of venous thromboembolism prophylaxis with fondaparinux in ischemic stroke

Unfractionated heparin (UFH), low molecular weight heparin or fondaparinux are recommended for venous thromboembolism (VTE) prophylaxis in acutely ill medical patients. There are limited data on the safety of fondaparinux for VTE prophylaxis in ischemic stroke. We examined adverse event frequency in hospitalized patients with ischemic stroke who received VTE prophylaxis with fondaparinux versus UFH.

We performed a propensity score matched analysis on a retrospective cohort of 644 consecutive patients with acute ischemic stroke receiving fondaparinux (n=322) or UFH (n=322) for VTE prophylaxis. Patients who received intravenous tPA and continuous intravenous infusions of UFH were excluded. The primary outcome was major hemorrhage (intracranial or extracranial) and the secondary outcome was total hemorrhage (major and minor hemorrhage) during hospitalization. We also examined the rate of symptomatic VTE.

Mean age of the matched cohort was 71.3±14.1 years, median NIHSS score was 4 (IQR 1-11), median duration of anticoagulant exposure was 5 (IQR 3-8) days, and 98.1% received antiplatelet medications. In the matched cohort, there were less observed major hemorrhages in the fondaparinux group 1.2% (4/322) compared to UFH 3.7% (12/322), but this difference was not significant (OR=0.33, 95% CI 0.08-1.10, p=0.08). There were also no significant differences in total hemorrhage (p=0.15), intracranial hemorrhage (p=0.48), major extracranial hemorrhage (p=0.18) and symptomatic VTE (p=1.00) between the groups.

Fondaparinux is not associated with increased hemorrhagic complications compared with UFH in patients with ischemic stroke. There were low rates of symptomatic VTE in both groups.