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


CONCLUSIONS
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.
Lopes
Renato D
RD
Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA.
Starr
Aijing
A
Pieper
Carl F
CF
Al-Khatib
Sana M
SM
Newby
L Kristin
LK
Mehta
Rajendra H
RH
Van de Werf
Frans
F
Mahaffey
Kenneth W
KW
Armstrong
Paul W
PW
Harrington
Robert A
RA
White
Harvey D
HD
Wallentin
Lars
L
Granger
Christopher B
CB
D054058:Acute Coronary Syndrome / Q000150:complications* / Q000401:mortality / Q000628:therapy*; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications* / Q000401:mortality; D015331:Cohort Studies; D005260:Female; D005343:Fibrinolytic Agents; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use*
D000925:Anticoagulants; D005343:Fibrinolytic Agents; D014859:Warfarin