Currently, there are many theories of varicose veins. However, the common main reason for varicose veins feet is considered a violation of valvular veins. As already mentioned, the valves of veins do not allow blood to go in the opposite direction, and provide only the flow of blood to the heart. Reasons for lack of function of valves of veins are different: this is thrombosis, their inherent failure, etc., no. In addition, the weakness of the walls of the veins and leads to insufficiency communicating veins.
What causes failure of valves of veins? When a person stands up, the blood by the force of gravity swoops.
When the muscles surrounding the deep veins of the legs are reduced (and this occurs when walking), these veins are emptied, resulting in increased venous pressure. By communicating veins with insufficient valves in the blood reaches the superficial veins. As a result of superficial veins is even more blood, which manifests itself in the form of stretching and expansion - of varicose veins.
In the early stages of the disease is still reversible and expansion is not so pronounced, however, over time, such an extension is permanent, that is, the veins "are not aligned." When lifting your feet up these veins are emptied, but the strain is not going anywhere.
The development of varicose veins is influenced by many factors:
Pregnancy. Pregnant women are often varicose veins. It is worth noting that most such veins is reversible and after birth gradually disappears. Varicose veins during pregnancy is associated with increased blood volume in women. Besides, the uterus with the fetus has a purely mechanical pressure on the veins that go from the feet. Note that vein, even central, very susceptible to external influence, in contrast to the arteries. In addition, during pregnancy on the wall of the vein is influenced by sex hormones such as estrogen and progesterone.
Prolonged standing. Some categories of people more prone to varicose veins in the legs, as their profession is associated with prolonged standing. These are teachers, surgeons, etc.
Increased intra-abdominal pressure. As already mentioned, the diameter of the vein varies in accordance with the phase of breathing: inhaling veins constrict, and when exhaling - is increasing. Straining, when intra-abdominal pressure is increased, as indicated dilatation, which is associated with a reverse flow of blood through them. For states that are accompanied by straining, include: chronic constipation, prostate adenoma, chronic cough, etc. In addition, these factors contribute to not only expand the veins on the legs, but other veins, such as rectal, manifested hemorrhoids, as well, according to some studies, and the veins of the spermatic cord, which is accompanied by a varicocele. Trauma and surgery on the foot may also contribute to varicose veins.
Age. With age, the walls of veins and their valves, grow old and become weak. They lose their elasticity, resulting in stretching.
Deep vein thrombosis. Many patients mistakenly believe that varicosity contributes to thrombosis of superficial veins, whereas in violation of patency of superficial veins (eg, thrombosis), blood can safely go into the deep. Varicose veins do not occur (deep veins do not expand!). When deep-vein thrombosis in these pressure rises, it reaches a level such that the blood passes through the communicating veins to surface. This, in turn, leads to their expansion.
Congenital abnormalities of blood vessels can also lead to the development of varicose veins. For example, when arteriovenous fistulas (fistulas), where there is direct discharge of arterial blood in the veins, causing them to increase pressure and there is a varicosity.