PT  - JOURNAL ARTICLE
AU  - L V Andersen
AU  - P Vestergaard
AU  - P Deichgraeber
AU  - J S Lindholt
AU  - L S Mortensen
AU  - L Frost
TI  - Warfarin for the prevention of systemic embolism in patients with non-valvular atrial fibrillation: a meta-analysis
AID  - 10.1136/hrt.2007.135657
DP  - 2008 Dec 01
TA  - Heart
PG  - 1607--1613
VI  - 94
IP  - 12
4099  - http://heart.bmj.com/content/94/12/1607.short
4100  - http://heart.bmj.com/content/94/12/1607.full
SO  - Heart2008 Dec 01; 94
AB  - Background: Warfarin for stroke prevention in patients with atrial fibrillation (AF) is well documented. However, it has not been examined in the prevention of systemic embolism.Objectives: To evaluate the efficacy of warfarin in preventing systemic embolism (embolism to limbs or viscera) in patients with AF.Methods and results: A combined Medline, Embase, Cochrane Library and SveMed+ search were made. Fifteen studies were included. Warfarin was better than antiplatelet agents for preventing systemic embolism with a 50% reduction of risk (odds ratio (OR) = 0.50, 95% CI 0.33 to 0.75) without increasing the risk of major bleeding (OR = 1.07; 95% CI 0.85 to 1.34). Warfarin compared with placebo resulted in a risk reduction of 71% (OR = 0.29; 95% CI 0.08 to 1.07) with higher risk of major bleeding with warfarin (OR = 3.01; 95% CI 1.31 to 6.92). Results of a comparison of warfarin with low-dose warfarin (OR = 1.52; 95% CI 0.40 to 5.81) or low-dose warfarin with aspirin (OR = 1.00; 95% CI 0.17 to 5.81) were inconclusive.Conclusions: Warfarin not only reduces the risk of stroke but is also better than placebo and antiplatelet agents in prevention of systemic embolism in patients with non-valvular AF. Warfarin increases the risk of major bleeding compared with placebo but not compared with antiplatelet agents.