What Happens
If you have symptoms of
deep vein thrombosis, testing will begin immediately
to determine whether you have a blood clot in your leg.
Often people with deep vein thrombosis do not have any symptoms. In
these people, this condition is usually suspected only after a blood clot is
discovered in the lung (pulmonary embolism). Typically, the
blood clot in the lung came from a deep vein clot in the leg that was not
causing symptoms.
Once you are diagnosed with deep vein thrombosis, treatment begins
if it is likely that the blood clot will grow or that a piece of the clot might
break loose and flow to the lungs (pulmonary embolism). If you have a blood
clot in your upper (proximal) leg vein, you will usually need to take
anticoagulant medication for 3 to 6 months, and possibly longer.1
After 3 to 6 months, your doctor may recommend that you continue
warfarin (such as Coumadin) on an ongoing basis to prevent deep vein clots from
recurring.2
Typically, if you have a blood clot in the lower (distal) deep leg
veins, you will need to take medicine to prevent more blood clots
(anticoagulant medicine) for 6 to 12 weeks.3 Sometimes
your doctor will not start this medicine right away. He or she will wait 24 to
48 hours to see if your blood clot is growing. If for any reason you cannot
take anticoagulants, your doctor will recommend that you take a
non-steroidal anti-inflammatory drug (NSAID), such as
ibuprofen, and monitor the blood clot with ultrasound.
The main goal of treatment is to prevent the blood clot from
growing or moving to the lungs. If a blood clot in the deep veins of the leg
breaks loose and travels to the lungs, it can cause
pulmonary embolism. Pulmonary embolism occurs in 25%
of cases of untreated, diagnosed deep leg vein thromboses.3 In people who receive treatment for deep vein thrombosis, the
rate of pulmonary embolism falls drastically. For more information, see the
topic Pulmonary Embolism.
Blood clots in the lung (pulmonary emboli) occur more often in
people with deep vein blood clots in the upper rather than the lower leg veins.
Only about 20% of blood clots in the veins of the calf will become larger and
extend into the upper leg or groin veins.4 Blood clots
that extend into the upper leg veins usually require treatment with
anticoagulant medication to prevent pulmonary embolism.
The recurrence rate for deep vein thrombosis varies depending on
what caused the blood clot and how it was treated. Recurrence is most common in
people who have continuing risk factors (such as cancer or
inherited blood-clotting problems) and in people who
have had more than one blood clot in the leg. Recurrence is lowest in people
who have a short-term risk factor, such as surgery or temporary
inactivity.
In about 25% of people who have had deep vein thrombosis with
symptoms, a condition called
post-thrombotic syndrome may develop within 8
years.4 This condition can cause pain, swelling,
discoloration, and sores on the leg. Post-thrombotic syndrome usually develops
within 2 years of the original blood clot.4 A recent
study showed that compression stockings can cut your chance of developing
post-thrombotic syndrome nearly in half.5