Veins can be altered for various reasons and dilate.These venous expansions are called varicose veins; being a major obstacle to the circulation of the blood; In addition to affecting the body aesthetics.The venous system has three interconnected layers: the capillary; It is the most superficial; the Subdermica; that unites the capillary veins with the profound and the Profundas which is the main.Varicose veins are formed in the first layer, or the capillary layer and can appear in any part of the body, being in the legs where are produced in its entirety; for reasons of gravity. The force of gravity makes things fall under its own weight down, takes care that the way of ida sanguinea(deel corazon hacia los miembros, a traves de las arterias) circulation is made very easily.How difficult is the rise of the blood to the heart, where blood goes by eliminating all impurities was picking up along the way. There are two factors responsible for defy the law of gravity and make the blood to raise: to)-valves (found in the interior of veins, facilitating the rise or impidiendo back down; b)-the pressure exerted by the muscles on the deep veins, that when contracting press them at times helping the blood pumping.We must know that the lower limbs that are furthest away from the heart; the route of the blood being to reach him, greater than in other members. There are two types of varice:1) – idiopathic or essential; Here we find the majority of varicose veins. They are the result of an alteration in the wall of veins (venous tissue weakness).The cause of this disturbance is not very clear. (2) – secondary; they occur in smaller quantities; they are veins that are born to replace some of the body. They occur from diseases of the liver; usually in cirrhosis, the liver becoming hard and fibrous preventing the blood can pass through him.This makes the veins coming out of it, to expand so blood can find other ways; giving origin to the varicose veins esophageal, situated in the esophagus. .