Varicose veins (varices)
Varicose veins can have various causes. On the one hand, the vein wall can be very weak in the case of congenital weakness, on the other hand the vein wall can become weaker due to heavy strain (a lot of standing without movement, obstruction of the blood flow for example due to pregnancy). In both cases, the vein wall gives way, which increases the diameter of the vein.
Due to the larger diameter, the venous valves can no longer close completely and the inversion of the blood flow away from the heart cannot be prevented. This causes the blood to back up, which further expands the vein wall. These so-called varicose veins are then visible.
The consequences of varicose veins can be an undersupply of the tissue from which the vein is actually supposed to remove blood. If the venous blood does not drain off, oxygen-rich blood cannot flow in either, so that the tissue is not properly supplied. As a result, leg ulcers can develop (leg ulcers).
In addition, the disturbed blood outflow can cause small inflammation spots on the vessel wall. The vessel wall is roughened at these inflammation sites, causing various blood components to be deposited there and blood clots to form. If the blood flow comes back into force, these small blood clots can be carried along and reach the lungs via the heart, where small vessels can then be blocked. This leads to a pulmonary embolism, which can also be fatal.
Phlebitis (thrombophlebits)
One speaks of phlebitis when veins located on the surface of the body become inflamed. Causes of such an inflammation are primarily varicose veins on the legs, while phlebitis can also occur on the arms as a result of infusions and permanent indwelling catheters. The inflammation can cause superficial swelling, but this usually does not affect the blood flow, which is the main part of the blood transported back to the heart through veins located deep in the body. In the worst case, a bacterial infection may occur, and an abscess may also form in the affected vein.
