Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a common condition where clots form in the deep veins of the legs or pelvis, and occasionally in the arms. These clots usually occur as a result of a serious medical or surgical illness causing problems with mobility. Examples of medical problems at high risk for DVT include stroke, paraplegia, and cancer treatments. Surgical patents at high risk for DVT include those who undergo joint replacement, abdominal or pelvic surgery, and surgery for multi-system trauma. Some patients may be at further risk of DVT due to they have thick blood, as a result of one or more inherited conditions called hypercoagulable syndromes. Blood tests are available for known syndromes and patients with unexplained DVT should be tested for them. The standard treatment for uncomplicated DVT is anticoagulation, either with warfarin or newer anticoagulants. Duration of treatment is typically 6 to 12 months but sometimes shorter or longer courses are prescribed. These patients typically have clot just in the leg veins. If the clot extends into the pelvis or abdomen, patients may develop severe pain and swelling of the legs, a condition known as phlegmasia. In cases of complicated DVT, catheter based interventions may be undertaken to dissolve the clot with enzymes or physically remove it with one of a number of devices. In many cases where acute clot is found in the pelvic veins, a chronic narrowing is found in the vein after the clot has been removed which is responsible for the acute thrombosis. This chronic narrowing can be stented. A well known example of this is May-Thurner syndrome, where the left iliac vein is compressed by the right iliac artery as it passes under the artery before joining the right iliac vein to form the inferior vena cava. Catheter based treatment of complicated DVT not only relieves acute pain and swelling, but prevents long term complications of DVT that can include chronic pain and swelling, varicose veins, skin changes known as stasis dermatitis, and skin ulceration. The long term symptoms are known as post-thrombotic syndrome.

Some patients are not candidates for anticoagulation, or fail treatment with anticoagulation. In this case they may receive an inferior vena cava filter, a mechanical device that is placed into the inferior vena cava, the main vein in the abdomen. Filters catch large blood clots that may travel from the deep veins in the legs or pelvis to the heart, a condition known as pulmonary embolism. Over time the clot is dissolved by our own clot dissolving enzymes that circulate in our blood stream. Inferior vena cava filters are very safe to place and they can prevent deaths from PE in the setting of acute DVT. However there can be problems with long term implantation of inferior vena cava filters so they should be removed as soon as they are no longer needed. Most but not all filters can be removed. Both placing and removing filters are catheter based, outpatient procedures performed through small punctures in the groin or neck.

Varicose Veins

Varicose veins result from damaged valves causing dilated, pressurized veins. The valves in our veins normally divide the column of blood that exists in our veins between our heart and our feet into a series of very short low-pressure columns. If the valves fail, the column gets longer and the pressure at the bottom of the column rises, much like the higher pressure at the bottom of a swimming pool. As a result, we usually see varicose veins in the legs, the most dependent part of the body where the pressure in the veins is highest. There are 3 sets of veins in our legs: deep veins, superficial veins, and perforator veins. The deep veins may have damaged valves after DVT, in which case symptoms are often worse. We usually don’t intervene on deep veins for valve disease since operations developed to treat this problem have generally not been successful. However it is useful to know if the deep veins are involved to help determine a patient’s prognosis. Most people with varicose veins have normal deep veins.

Superficial veins are always diseased in patients with varicose veins. We have several long superficial veins which have names, including the greater (or long) saphenous vein, the lesser (or short) saphenous vein, the anterior accessory saphenous vein, and the intersaphenous vein. The greater saphenous vein runs up the inside of the leg from the foot to the groin, where it drains into a deep vein called the femoral vein. The lesser saphenous vein runs up the back of the lower leg from the foot to the knee where it drains into a deep vein called the popliteal vein. Patients usually have quite pronounced varicose veins and symptoms if the saphenous veins are involved. These are the veins that used to be stripped in the past. They are now treated with a minimally invasive procedure called an ablation, where a probe is inserted into the vein through a small puncture under ultrasound guidance. After the surrounding tissues are anesthetized, the vein is closed by heating it with the probe. Depending on the type of probe used, heat is generated either by with laser energy or radiofrequency energy. This procedure is commonly done in the office and takes about 30 minutes. This technology can also applied to the anterior accessory saphenous vein, a vein that is found on the anterior thigh, and to perforator veins. Perforator veins run horizontally in several locations between the deep and superficial veins. They are usually found in discrete locations such as the inner aspect of the leg, including the distal shin (Cockett’s veins), below the knee (Boyd’s vein), above the knee (Dodd’svein) and midthigh (the Hunterian vein).

Unnamed superficial varicose veins can be treated with either stab phlebectomy or sclerotherapy. Stab phlebectomy is an outpatient procedure where larger superficial veins are dissected out through very small incisions and removed or tied off. If only a few incisions are required, it may be performed in the office under local anesthesia but if many incisions are required, it is frequently performed under anesthesia in a hospital or ambulatory surgery center. Sclerotherapy is a procedure where smaller veins (usually 2-3 mm in diameter or less) are injected with an chemical irritant that causes them to scar down. Clusters of tiny surface veins called spider telangiectasias can be treated with sclerotherapy but are usually best treated with a laser that is placed on the skin.

Since the treatments vary depending on which veins are involved, it is critical to identify which veins are involved before a treatment plan is formed. The veins are best assessed with ultrasound, so a venous ultrasound is a critical tool for diagnosing and following venous insufficiency. Before any of these treatments are recommended, patients should undergo a trial of conservative medical therapy with a prescription compression stocking. These come in knee-high, thigh-high, or even panty hose configurations and may be custom made to fit virtually anyone’s measurements. Patients should try a prescription compression stocking for at least 3 months before considering an intervention.

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