I am posting this here because I'd like Dr. Brandes and others to tell me why I am wrong. I don't want arguments that require a medical degree to understand. Just high school, please. But I do want them to be an open-and-shut case.
This may be true for points that I have not researched much, but not for the whole thing.
Let's see, what do I remember?
It's caused by many things, infections, injury, congenital conditions. Its likely in some cases associated with scarring.
It's 4 time more prevalent than MS, so could include MS.
It causes reflux, which could reach the brain.
It is according to http://en.wikipedia.org/wiki/Tricuspid_regurgitation
, usually asymptomatic.
See also http://en.wikipedia.org/wiki/Jugular_venous_pressure
I think it causes both CCSVI and MS.
I know that sounds like a mouthful, but I am quite serious. It causes instantaneous pressure increase in the head veins. It starts the cascade of events, which over a period of years will change to MS symptoms. The instantaneous pressure increases, averaged over time, cause the veins to react by stretching and growing colatterals. It is important to remember the two greatest forces at work: the heart muscle, and gravity.
I got this idea from a discussion on Colin Rose's website. But you can forget him. I never did convince him that veins have anything to do with MS.
In the first instance, there doesn't seem much reason for the heart to pump venous blood away from itself. But it is pumped toward the lungs. It is for this reason that the vessel carrying venous blood toward the lungs is actually called an artery. This transfer of blood from heart to lungs is the only outward-pumping force generated by the right side of the heart. It is driven by contractions of the right ventricle. It is normally not enough force to overcome the force of gravity, because that side of the heart is not supposed to pump blood upward. Reuse, yes, recycle, no. The blood that goes up comes from the left atrium.
Please forgive all my repetition of primary material to you. I go on, only because I am new to this area, and don't know it from the same sources as doctors do. All I have is a 'fresh pair of eyes.' So I go on.
The right heart has a different kind of job to do from the left heart. During relaxation, of the left ventricle, newly oxygenated blood must be moved by negative pressure, or suction, only laterally from the lungs by the left heart, from where it is distributed to the body, also by the left heart.
During contraction (squeezing) the heart must be much stronger on the left, having to pump oxygenated blood from the chamber above, to all points served by oxygen, which is everywhere in the body, including the head. Everything below heart level is assisted by gravity. Everything above heart height, conversely, which must go upwards for the brain and senses, must be pumped against gravity, when the person is upright.
On the right, the heart, as I have said, does not need as much contractile, outward, squeezing force as 'relaxing' inward, suction force. It must only contract and pump outward more or less laterally, to the lungs, where blood gets oxygenated by breathing. (It may go, for some non-oxygen-related cleaning, to the liver and gall bladder, but I'll come to that later.) But it must retrieve by suction, all blood that went down as far as the toes. In the upward direction, it (the right heart) need never work against gravity when contracting, because gravity is available to get blood back down to the heart, so it goes down, as appropriate, during the suction, relaxation phase of the heart muscle's movement, from everywhere it has to above heart level.
There is a valve, the tricuspid valve, that prevents pumped-outward blood from being pumped upward toward the right atrium, by closing when there is positive pressure from the lower right chamber (i.e., when it squeezes). If this valve fails, there is said to be a condition called tricuspid insufficiency. Other nouns are regurgitation, and incompetence.
In this condition, blood from the right lower chamber can be, and is, pumped upward, backward through the incompetent valve. So regurgitation can be pumped upward toward the right atrium, the right jugular, even the right brain. These contractile pulses of venous blood cause the total jugular pressure to rise. If the valve fails but the breaches are still small, there may be multiple small streams of reflux, each with some pressure and pulsatility above the neck. When the members supporting the closed valve give way altogether, the valve becomes stuck open.
After some years of the added venous pressure (averaged out over the reflux pulses), the veins of the head balloon to a larger shape -- the body's response to the additional pressure. The newly formed veins do not always lead anywhere, and strictures can keep the pressure inside the head, where the veins will expand and add collateral vessels to try to improve the outflow. Sometimes, a stricture in one vein causes it to enlarge above the vertical level of the stricture. This may possibly be the only effect, over time and so no lesions will occur, if the venous reflux never reaches the CNS.
If the reflux reaches the Blood-Brain Barrier or other places in the CNS drained by the refluxing veins, the MS symptoms will occur.
This disease (tricuspid insufficiency) is prevalent in 1% of the population. 50% of the time it is asymptomatic, so we are down to 0.5 percent of people who have symptomatic disease. This is approximately twice the prevalence of MS.
It could be that the additional work the heart has to do during gestation is responsible for the 'pause' in MS sometimes seen during pregnancy. It could be that women,have stronger ventricular contractions in the right heart than men, or weaker tricuspid valves, therefore twice as many get MS. Possibly menstruation is involved. This is definitely an area for further study.
And also right ventricles being too big or powerful after pregnancy, so more reflux happens.
The differences in prevalence at different latitudes may be due to different sleeping schedules. Nocturnal predation is common in equatorial areas. Diurnal predation, and therefore more indoor living, occurs at polar areas. Posture when lying down (asleep) seems to have great bearing on the drainage by veins. At extreme latitudes there is a six-month night, or period of darkness. Humans may have responded to the daylight length differences by hibernating, during which postural changes would be adapted to fairly successfully. There should therefore be a low prevalence of TI (tricuspid incompetence) and therefore in CCSVI and MS in these polar regions. Far fetched as that sounds.
It should be easy to test for CI. A pulsatile liver is considered a positive diagnosis. This statement implies that the liver has reflux from the right heart. This is because the deox blood is pumped to the liver as well as the lungs, for cleaning. The phasing of the reflux should correspond with the right ventricle contractions.