What is the "formula" to determine whether or not a patient qualifies for a Watchman?

I'm having a very hard time to see if one would meet my need (seemingly infinitely researching) to avoid an oral anticoagulant to slow my movement towards central vision blindness caused by one. I have wet macular degeneration and whereas no, I don't want a stroke ("duh") I do not want to go blind which appears inevitable with this condition.

At the very least, I don't want to take a medicine (for paroxysmal) AFIB which statistically does hasten that condition thus maximizing my period of sightedness.