POEMs
Patient-Oriented Evidence That Matters

Heparin Treatments for Acute Coronary Syndrome

DAVID SLAWSON, M.D.

American Family Physician. 2006;73(5):890.

Clinical Question: Is the low-molecular-weight heparin (LMWH) enoxaparin (Lovenox) more effective than unfractionated heparin in the management of acute coronary syndromes?

Setting: Inpatient (any location) with outpatient follow-up

Study Design: Randomized controlled trial (double-blinded)

Allocation: Uncertain

Synopsis: Previous studies show that LMWH and unfractionated heparin are similarly effective at 30 days of follow-up in the treatment of high-risk patients with acute coronary syndromes. The investigators reported the follow-up for more than 96 percent of 9,978 patients with acute coronary syndromes at six months and one year. The patients received enoxaparin or unfractionated heparin (uncertain allocation concealment) with standard therapy, including aspirin and clopidogrel (Plavix) when indicated. All analyses are based on intention to treat. All-cause death at one year, nonfatal myocardial infarction, and rehospitalization occurred at a similar rate in patients receiving enoxaparin and unfractionated heparin.

Bottom Line: The LMWH enoxaparin is no more effective than unfractionated heparin in the treatment of patients with acute coronary syndromes. (Level of Evidence: 1b)

DAVID SLAWSON, M.D.

  1. 1.Mahaffey KW, et al. High-risk patients with acute coronary syndromes treated with low-molecular-weight or unfractionated heparin. Outcomes at 6 months and 1 year in the SYNERGY trial. JAMA. November 23, 2005;294:2594-600

POEMs (patient-oriented evidence that matters) are provided by Essential Evidence Plus, a point-of-care clinical decision support system published by Wiley-Blackwell. For more information, see http://www.essentialevidenceplus.com. Copyright Wiley-Blackwell. Used with permission.

For definitions of levels of evidence used in POEMs, see https://www.essentialevidenceplus.com/Home/Loe?show=Sort.

Primary Care Update, a free podcast focused on POEMs, is available on Apple Podcasts and Spotify.

This series is coordinated by Natasha J. Pyzocha, DO, contributing editor.

A collection of POEMs published in AFP is available at https://www.aafp.org/afp/poems.

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