I haven't and truthfully, after having survived two separate DVT's wouldn't want to press my luck with anything other then what is scientifically proven. Much like everyone else I hate Coumadin, or any other med for that fact. But it what keeps me going and in the over all 'big picture' that's what's important.
The only "true" medically study regarding any type of supplement/vitamin which offers some hope is Vitamin "E". Harvard Medical School ran a small study last year which showed that patients who were not on any type of anticoagulant were offered some protection from clots. Keep in mind that even though this study had some very good news it was performed on a small group of patients and in order to validate it would have to be done on a larger level. My clotting doctor was part of this trial so I trust the findings. Might be something you may want to consider after your Coumadin/Warfarin Treatment as a preventative measure.
Now, should your physician place you one life long coumadin, it's not the end of the world. I've been on coumadin life-term since 2001 on a very low dose (with a target INR of 1.5-2.0) at this level the bleeding issues are lessened and I pretty much do the same things I did before Coumadin (riding mountain bikes, soccer, hiking, etc.). Hasn't impacted my life in any negative way. If he does go this route, let me know and we'll talk some more.
Tom in Connecticut