Previously, it was considered that the risk of stroke could be reduced by removing or blocking off the Left Atrial Appendage (LAA). This new study indicates that this can lead to 4 times the risk of AF with no reduction in the number of strokes:
medscape.com/viewarticle/87...
So it would appear unsafe to stop anti-coags after LAA removal or blocking. At the very least a lot more research is needed into this.