I'm mostly VTOS with very little NTOS. Most of my head symptoms were caused by TMJD. Both my TMJD and TOS seem to be largely caused by muscle tension, although that may not be the whole picture.

I don't know the risk of stroke.

I always share my tips here so you can look through my posts. You need to start trying stuff like scalene stretches, first rib adjustments, relaxation audios, etc. to see if they help--provided you have already seen the appropriate health care providers to get all the correct tests.

Good luck.