Deep Venous Thrombosis (DVT)

Deep Venous Thrombosis (DVT) is the formation of a clot ('thrombus') in a vein deep in the body, usually in the lower leg, thigh, or pelvis. Blood clots may form in the blood vessels when the blood does not flow properly, as occurs in people with chronic venous insufficiency.

If the veins are blocked with a blood clot, two problems can occur. If the clot blocks the blood flow back to the heart, the leg can begin to swell, ache and throb. Even more seriously, the clot in the leg vein may break away and travel to the heart and lungs, where it can cause significant damage or death. DVT can be life threatening if a blood clot travels from the leg veins to the heart or lungs (called a pulmonary embolus). Affecting approximately 300,000 people each year in the U.S., pulmonary emboli cause more deaths than breast cancer, AIDS, and accidents combined.

Risk factors for developing blood clots include long air or auto travel, surgery, advancing age, pregnancy, and more (see Risk Factors for DVT, below). In addition to the risk factors associated with venous disease and DVT in particular, abnormal clotting may occur in people with inherited clotting disorders called thrombophilias. These can easily be diagnosed with simple blood tests, but a high index of suspicion is usually needed before performing such tests. If you have had a blood clot already for no apparent reason then you probably should be investigated for having thrombophila. A family history of blood clots in veins, early heart attack in parents or siblings (under age 50) or an early stroke are also reasons to investigate the possibility of an inherited clotting disorder.

Symptoms of DVT

Deep vein thrombosis (DVT) is often first noticed as a "pulling" sensation in the calf of the lower leg, and it can be quite painful. Symptoms also include associated warmth, redness and swelling. The swelling often extends to above the knee. Unfortunately, DVT is silent or subtle in the majority of patients.

Risk Factors for DVT

Some patients are at higher risk for developing DVT. These include people with one or more of the following characteristics:

  • Over 40 years of age
  • Fracture of leg bones
  • Recent surgery
  • History of venous disease / varicose veins
  • Prolonged immobility/paralysis
  • Blood Clotting Disorders
  • Obesity
  • Hormonal medications
  • Cancer
  • Infection

Pharmacomechanical Thrombolysis for Deep Vein Thrombosis

The newest minimally invasive methods to remove blood clots are mechanical and chemical techniques called pharmacomechanical thrombolysis. With one small needle stick, surgeons at our program are able to place devices that dissolve clots by softening them and vacuuming them out of the body in a matter of hours. This removes clots, allowing patients to return to normal activity more quickly than after traditional methods of DVT management.

The goal of treatment is to dissolve the blood clot so that it does not cause damage to the leg veins or travel to the heart or lungs. The most common form of treatment is medication to prevent clotting, also known commonly as "blood thinners." There are two types of blood thinners, an immediate-acting medication and a slower-acting form. The immediate-acting medication requires injections or intravenous treatment. The slower-acting form is a pill that takes several days to begin working. In most case, we administer both the immediate medication (heparin, Lovenox) and the oral type until it begins to take effect, at which point the injectable or intravenous type is stopped. Oral blood thinner is then continued for at least six months.

Most treatments can be done on an outpatient basis, and injections of immediate-acting blood thinners can be self-administered at home. Patients with significant risk factors may be hospitalized for several days until the oral medication takes effect.

In some cases, a clot may be so extensive, or the risk of blood thinners so great, that patients need another type of protection. These patients may require the placement of a vena cava filter. The vena cava is the main vein in the abdomen, and both leg veins lead to the vena cava. A vena cava filter can be thought of as a strainer or colander that traps any blood clots that may travel from the leg veins to the heart. Vena cava filters prevent the life-threatening complication of leg vein blood clots—pulmonary embolus. This filter is designed in such a configuration that it is self-cleaning i.e.: once a clot is trapped, it is slowly dissolves over time.