Well in fact a significant part of your venous drainage from the head is aided by the negative pressure in your chest that allows you to breath, it is called the thoracic pump. SO take a good deep breath and the same "sucking" (negative pressure) that pulls air in also pulls the blood through the veins.
Exercise increases oxygenation too.
Stress results in cortisol and fight or flight hormones that impact your body system wide causing vasoconstriction in some areas, vasodilation in others, changes in permeability of the endothelium etc. These changes would be negative for CCSVI.
Blood pressure has to do with arteries......veins are pretty much passive.
I'm not offering medical advice, I am just a patient too! Talk to your doctor about what is best for you...
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