Greetings from the epicenter of the earthquake.
I am so, so sorry to hear of your troubles. If your flow was decent earlier this year, who knows what is going on now? There is so much to unravel.
I also had a dramatic downturn several months after angio, and thought the worst. The good news is that I recovered *so much better* than anyone would have expected. It wasn't perfect, but it happened, and if you had asked in the spring it would have seemed impossible. I dearly would have loved a window into my body during the acute issues and after. What was going wrong? Where? How did recovery happen?
There are so many systems that interconnect, and so many different theories of what is going on when a person has an MS flare-up. If you did have a positive d-dimer, it does not even necessarily indicate a blood clot. Interestingly, many people with MS have a high d-dimer during flare-ups (this has been discussed here but I can't find it right this minute -- Marie had great info on it). I am going to try to get some links for you. I have had a very high-d-dimer during flare-ups, but no clots on chest x-rays. However, no one has scanned other areas in the past. Could there have been clotting elsewhere?
I hope this doesn't sound cold or analytical when you are having such a personal crisis. Believe me, my heart is with you. I know those dark places, and I am sending you warmth and light and hope for the best recovery.
Bottom line -- I believe that I recovered so well because my vascular system was better able to handle the event I had, whatever caused it. I deeply hope the same will be true for you, and for other people.