Venous insufficiency is characterized by a blockage in the normal forward flow of blood through veins in the legs and up to the heart, as well as a backward leakage of blood due to faulty valves. Causing swelling, discomfort and ulceration in the legs, venous insufficiency is commonly caused by blood clots, vein inflammation and high blood pressure in the veins in the legs.
Blood Clots
According to the Cleveland Clinic, one of the most common causes of venous insufficiency is blood clots. Blood clots block the forward flow of blood through the vein and up to the heart. A specific type of blood clot called a deep vein thrombosis, or DVT, that commonly forms in a vein in the leg can cause blood to build up and blood pressure to rise. This in turn puts too much strain in the valves of the vein, causing them to expand and lose their ability to function normally, according to Vascular Web. Therefore, anyone with a history of a DVT or other blood clot is more likely to develop venous insufficiency due to this type of valve damage.
Phlebitis
Phlebitis is a term used to describe a superficial or deep vein that has become inflamed. Inflammation typically occurs when the normal circulation of blood through the affected vein becomes impaired. As circulation slows, blood pressure in the vein rises and venous insufficiency can develop. According to the University of Virginia Health System, injury to a vein through trauma, surgery, repeated injection or blood clot can cause phlebitis and lead to venous insufficiency. When phlebitis occurs in a deep vein in the leg, it is often accompanied by a potentially life-threatening blood clot and therefore requires prompt medical intervention.
Lifestyle Factors
High blood pressure, or hypertension--especially in the veins in the legs--can cause venous insufficiency by damaging the valves inside the veins that are responsible for preventing the backward leakage of blood, according to Vascular Web. A number of lifestyle choices and behaviors can lead to high blood pressure. For example, sitting for extended periods of time or standing on your feet for a prolonged period can cause the blood to stagnate in the veins in certain areas of the legs. This pooling blood blocks normal blood flow and elevates blood pressure. According to the University of Virginia Health System, smoking, obesity and lack of exercise can also cause venous insufficiency.
