Fondaparinux associated with better outcomes than LMWH in NSTEMI study

Fondaparinux was associated with lower risk of major bleeding and death than low-molecular-weight heparin (LMWH) for patients with non-ST-segment elevation myocardial infarction (NSTEMI), a recent prospective study found.

Researchers used data from a Swedish registry that included 40,616 consecutive patients who had an NSTEMI and were treated with either fondaparinux or LMWH between 2006 and 2010 to conduct their prospective multicenter cohort study, in which patients were followed for up to 180 days. Results were published in the Feb. 17 Journal of the American Medical Association.

Overall, 36.4% of the patients were treated with fondaparinux and 63.6% received LMWH. The fondaparinux group had a lower rate of in-hospital bleeding events: 1.1% versus 1.8% (adjusted odds ratio [OR], 0.54; 95% CI, 0.42 to 0.70). They were also less likely to die while in the hospital: 2.7% versus 4.0% (OR, 0.75; 95% CI, 0.63 to 0.89). The differences between groups on these outcomes extended out to 30 and 180 days, and there were no significant differences in rates of recurrent myocardial infarction (MI) or stroke during the study follow-up. Results were similar in subgroups of patients with renal dysfunction and in those who had undergone early percutaneous coronary intervention (PCI).

This registry study confirms previous randomized, controlled trial evidence that fondaparinux is associated with lower bleeding and mortality risk in NSTEMI patients than LMWH, the study authors concluded. This real-world investigation included more patients with a history of MI, stroke, or renal dysfunction than the randomized OASIS-5 trial, they noted. However, the present study was also limited by the likelihood of residual confounding, possible underestimations of bleeding events, and lack of information about the dose and duration of fondaparinux or LMWH.

Under European Society of Cardiology guidelines, fondaparinux is recommended as the first-choice anticoagulant for NSTEMI patients whether or not they undergo PCI. However, the American College of Cardiology/American Heart Association guidelines on the topic don't choose a specific anticoagulant for PCI patients and recommend either fondaparinux or enoxaparin for other NSTEMI patients, the study authors noted.