Varicose veins are leg veins which do not pump blood effectively back to the heart and can be often seen as bulging veins just underneath your skin on either leg. These varicose veins have valves in them which are not working effectively so that blood which is meant to be pushed towards the heart, leaks downwards toward the legs. There are other leg veins which are still working, so blood does eventually arrive through other routes to your heart. However, varicose veins do exert added pressure on your circulatory system. Read More.