I am an ophthalmologist and your problem sounds like vascular flow to the eye and ultimately the brain is constricted and that can cause transient obscurations of vision. With EDS people get POHTs (postural orthostatic hypotension syndrome) which causes blood pressure issues and blood flow problems. I have had it for years ... in particular the vision tunnels down and it usually happens upon standing or positional changes. I am not a cardiologist but maybe a beta blocker, the long acting kind like Metoprolol, can help if it's due to a rapid heart rate, like it is with me, and if you slow down the "squeeze" of the heart and let it get a more complete pumping of blood it can improve your symptoms. I hope it helps
