PFO and blood clots

     I have had 2 blood clots.  One after a hysterectomy: this one landed up in the portal vein of my liver. The second clot, many years later ended up in my colon.  It is unclear weather the first clot unclogged and recloggged or if the second was a new clot.  I had just donated blood and was playing tennis and I feel I was dehydrated. Previous collateral veins had disappeared. I was put on Coumidin after the second clot.  I have been on it for 12 years.  I worry about the dangers from coumidin as a consequence of a head injury or a traffic accident or fall.
     I had 2 babies that died in the third trimester for no apparent reason.  They appeared perfect.  
     I have had every test available and the clotting can not be replicated.  Consequently, no reason or clotting factor can be determined.
     Recently I had an Echocardigram with Doppler.  The test revealed a small PFO.  If I get the PFO repaired can I safely go off coumidin?  


This discussion is related to PFO, MVP, arhythmia.