Deep vein thrombosis (DVT) is a condition in which a blood clot forms in one of the deep-seated veins in your body.
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Certain genetic conditions increase your risk for DVT, as do medical conditions (such as obesity or pregnancy) and certain medications. Lifestyle factors such as sitting for extended periods of time or smoking also increase your risk of DVT.
Whatever the cause, we can help mitigate symptoms and lessen the likelihood of serious problems caused by DVT.
One acute and serious problem that can occur with deep vein thrombosis is when the clot or part of the clot breaks away and travels to the lungs, causing pulmonary embolism (blockage from a clot in the lung). This is a serious development that requires immediate medical attention.
Chronic or long-term DVT can also cause problems locally. Though not life threatening, these complications can be painful and debilitating.
Early symptoms of DVT include swelling, pain, warmth and redness in the involved leg. The location of the blood clot in the body determines how we treat the problem.
Blockage below the knee
When the clot or blockage is limited to the blood vessels below the knee (the tibial veins), your body repairs itself in 90 percent of all cases. The blood vessel finds a way around the blockage and restores proper blood flow.
This restoration process takes between three and six months. During that time, we usually provide anti-coagulant or anti-clotting medication and follow the patient closely with ultrasound checkups.
Blockage above the knee
When the clot extends above the knee joint and impacts the larger femoral or iliac veins, the risk for hypertension (increased blood pressure) in the veins that supply the affected limb increases. Between 40 to 60 percent of patients who have DVT of the ilial femoral segment of the vein in the thigh or pelvis will experience venous hypertension.
Chronic venous hypertension causes pain and swelling of the limb, further restricts blood flow and can ultimately lead to ulceration and open sores.
If the clot or obstruction is limited to the femoral vein in the thigh, we rely on compression of the calf and foot (using compression stockings and socks) and the body’s natural development of workaround venous pathways. Sometimes we will use lysis if these clots in the femoral vein are found early (within the first three weeks) to reduce long-term risks of venous hypertension. Currently, there is little available to improve the chronic obstruction process.
If the obstruction extends into the pelvis, venous thrombolysis (clot buster medication) and possibly venous stenting (the use of metallic mesh tubes to hold the vein open) of the responsible iliac vein have been very successful. If the clot is more than one month old, then the clot buster is not as effective, but outcomes can be improved with stenting.
If appropriate, we can insert a stent higher up, all the way to the inferior vena cava, which drains blood from the lower body.
Several companies are developing stents specifically for use in the venous system, but these are not commercially available in the United States. However, even with existing technology (stents used primarily for arteries), we have had excellent success in improving chronic blockage of the pelvic venous system.
We have evaluated and treated a large number of patients with chronic DVT. And, we have had very good long-term success in treating patients with stents.
We have also helped patients who have had problems with previously placed stents. For these patients, we can stent either around or through the earlier placed stents to decrease the pressure of veins in the legs and to improve their symptoms.