When your heart pumps, a big muscle pressurizes a lot of blood. This blood will move along the path of least resistance. The paths lead all over your body. If the path to your legs is easier (less resistance) than the path to your brain, guess where the blood will go? Stenosis anywhere causes the flow to be less at that location, and the path of least resistance downstream of any point in the circuit, is the path blood will seek. Downstream is anywhere blood flows toward (a circular definition). If there is a stenosis, less blood will flow toward that stenosis (in a given time) than if it were not there, along that path. Resistance to flow is always in the downstream direction. So if resistance increases downstream of the brain, (instantaneously, presuming collateral growth is not immediate) it is also increased in the direction arterial blood is flowing toward the brain. To the heart, the brain "loop" has had an increase in resistance. Less blood will flow in. If you want the same amount, you have to increase the pressure pushing it in. If you don't increase the pressure, or increase the resistance anywhere else, less blood will flow, in a given time, toward the brain. That means the movement of a given volume of blood has slowed down. Or that for a given amount of time, less blood will pass a given point. Same thing.
If the path towards the brain has more resistance, the path toward the feet may have an increased flow. That might have several effects. Initially, you might get warmer feet. But because the leg veins have to bring more blood up, they may wear out faster. The feet may swell, as well as being warmer.
One way we have of compensating for arteries congesting an area is to shrink the diameters of inflow or ouflow vessels feeding that area, thus increasing the resistance and slowing the flow. Note that this is a reaction in the feet, to a stenosis in a neck vein.
Now because of a neck vein stenosis, we can get rid of, and acquire less heat in our feet, because we have slowed the flow to allow more to reach the brain. Also, if there is less flow in the legs, to allow constant brain flow, the legs will have less energy available. Hands are a similar situation. Same with lungs, etc, probably following the order of their importance to our survival. The load on the heart for all this has to have increased, because it is easier to get blood down to the feet than up to the brain. Yeah, we might be more tired.
Now balloon the jugular stenosis. Bingo, circulation to the brain increases, and because of that we need to do less restricting of foot flow. Now all of a sudden, we can more easily (with less smooth muscle effort) get blood, and heat, into and out of the feet. We have to keep up our brain flow, even if it means the energy has to come from increasing brain blood pressure, and keeping hand and foot vessels smaller. Get rid of the neck stenosis, and all of the circulation benefits.
"Try - Just A Little Bit Harder" - Janis Joplin
CCSVI procedure Albany Aug 2010
'MS' is over - if you want it
Patients sans/without patience
I am not a doctor. Do not take anything I say as medical advice.