atrial fibrillation and stroke prevention - Continuing Medical ...

Essentials in Primary Care Conference
Wednesday, July 31, 2013
Current Use of Warfarin in Preventing
Stroke: A Recent Meta-Analysis
• Previous Hart Meta-analysis (Ann Int Med 1999) with Warfarin
revealed stroke or systemic embolism event rate at 2.09% per
year with only 2 of 6 trials with time in therapeutic range (TTR)
above 60%
• This updated meta-analysis included 8 Randomized trials
(including RE-LY, ROCKET-AF, ARISTOTLE) with 32,053 patients
• Overall INR was in therapeutic range (TTR) in 7 of the 8 trials
more than 60% of the time
• Incidence of stroke or systemic embolism now at 1.66% per year
(down from 2.09% per year) with warfarin Rx with better TTR.
TAKE AWAY POINT:
• There has been a significant improvement using warfarin in the
proportion of time spent in therapeutic anticoagulation with a
resultant decline in observed stroke rates.
Agarwal S, et al. Archives Intern Med 2012;172:623-631
Can We Make Warfarin Use
Easier for the Patient?
• Study: VKA patients on stable dose of warfarin for 6
months currently on monthly f/u (n=226) with stable
INR
• Intervention: f/u Q4 weeks vs Q 12 weeks
• Outcome :
TTR (4 wk vs 12 wk): 74.1% vs 72.6% (non inferior)
Major bleeding, VTE, death: No difference
Intervention: f/u Q4 weeks vs Q 12 weeks
• Conclusion:
Q 3 months f/up of warfarin monitoring is
acceptable in a patient with a stable and
therapeutic INR
Schulman S, Ann Intern Med 2011;155:653-659
Jan Basile, MD
Atrial Fibrillation & Stroke Prevention