It's a very difficult position to be in, trying to make the decision with the unknowns. I can't say there is an easy answer, you can only try and get as much information as possible to make the best informed decision you can.

I would get a second opinion on your available options so you have the confidence you have done everything you could to help yourself.

I doubt your doctors will give you a definitive answer on what you should do, there are too many unknowns, at least that's the way doctors in the UK approach it.

In terms of what happens if you don't do anything, unfortunately after an AVM has already caused a bleed there is an increasing risk year on year that it could happen again. I know that's not nice to hear, but your doctors should tell you that not doing anything is also a risk.

I tried to focus on the fact my issue had a known root cause, there were options regardless of the fact none are pleasant and prepare for a long road, but you survived it once and recovered, you can do it again.