Warfarin use and outcomes in patients with atrial fibrillation complicating acute coronary syndromes

Am J Med. 2010 Feb;123(2):134-40. doi: 10.1016/j.amjmed.2009.09.015.

Abstract

Background: We examined warfarin use at discharge (according to Congestive heart failure, Hypertension, Age>75 years, Diabetes, Prior Stroke/transient ischemic attack score and bleeding risk) and its association with 6-month death or myocardial infarction in patients with post-acute coronary syndrome atrial fibrillation.

Methods: Of the 23,208 patients enrolled in the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy, Platelet IIb/IIIa Antagonist for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network A, and Superior Yield of the New Strategy of Enoxaparin, Revascularization and Glycoprotein IIb/IIIa Inhibitors trials, 4.0% (917 patients) had atrial fibrillation as an in-hospital complication and were discharged alive. Cox proportional hazards models were performed to assess 6-month outcomes after discharge.

Results: Overall, 13.5% of patients with an acute coronary syndrome complicated by atrial fibrillation received warfarin at discharge. Warfarin use among patients with atrial fibrillation had no relation with estimated stroke risk; similar rates were observed across Congestive heart failure, Hypertension, Age>75 years, Diabetes, Prior Stroke/transient ischemic attack (CHADS(2)) scores (0, 13%; 1, 14%; > or = 2, 13%) and across different bleeding risk categories (low risk, 11.9%; intermediate risk, 13.3%; high risk, 11.1%). Among patients with in-hospital atrial fibrillation, warfarin use at discharge was independently associated with a lower risk of death or myocardial infarction within 6 months of discharge (hazard ratio 0.39; 95% confidence interval, 0.15-0.98).

Conclusion: Warfarin is associated with better 6-month outcomes among patients with atrial fibrillation complicating an acute coronary syndrome, but its use is not related to CHADS(2) score or bleeding risk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Coronary Syndrome / complications*
  • Acute Coronary Syndrome / mortality
  • Acute Coronary Syndrome / therapy*
  • Aged
  • Anticoagulants / therapeutic use*
  • Atrial Fibrillation / complications*
  • Atrial Fibrillation / mortality
  • Cohort Studies
  • Female
  • Fibrinolytic Agents
  • Hospitalization
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / epidemiology
  • Retrospective Studies
  • Treatment Outcome
  • Warfarin / therapeutic use*

Substances

  • Anticoagulants
  • Fibrinolytic Agents
  • Warfarin