Are You at Risk?
You just got home from vacation last
night. You spent 6 hours on an airplane traveling back from some exotic
location. In the morning you wake up with a painfully swollen left calf. Should
you be worried? The answer is a resounding yes!
What is a DVT?
DVT or deep vein thrombosis
is a life threatening medical condition with serious consequences that affects
2 million Americans each year. A blood clot forms in a deep vein within the leg
or in some cases an arm. The most common presentation of a DVT is a painful,
swollen leg. The clot can travel to your lung causing a PE or pulmonary
embolism, which kills over 300,000 people in the US per year. That is over 7x
the number of people that are killed annually in automobile accidents.
What is the
postthrombotic syndrome?
DVT can also cause something
known as the postthrombotic syndrome in the years following the event. This
condition includes a painful swollen leg, itching, and difficult to heal leg
ulcers near the ankle. It is caused by continued blockage of the veins or
destruction of the valves in your veins that normally prevent blood from
pooling down by the ankle. To avoid this condition, proper medical care is
needed. Patients with DVT should be seen by a Vascular Surgeon to avoid this
difficult to treat chronic illness. The best way of avoiding this condition is
to use doctor prescribed compression stockings or socks following the DVT.
Should you develop a leg ulcer following a DVT, there are new treatments that
we employ to help heal the wounds in far less time than in the past.
What is your risk for
DVT?
The best way of finding out
your risk for DVT is to talk with your doctor. I have spent over 20 years
taking care of patients with DVT. Sometimes the only risk factor is a long car
or airplane ride during which the patient was immobile for many hours. There
are known risk factors for DVT, and you should be aware of them. The greatest
risk is recent hip or knee replacement surgery, serious trauma with a broken
leg or pelvis bones, and spinal cord injury. Other important factors are a
prior blood clot in you or a family member, a family history of clotting
disorders, and age over 75. There are other less obvious health problems that
also put you at risk for DVT: cancer, recent surgery, being in a cast, bed
rest, being over age 60, the use of birth control pills, hormone replacement
therapy, inflammatory bowel disease, being overweight, heart disease, lung
disease, and even just garden variety varicose veins.
How is DVT diagnosed?
If you suspect you may have
a DVT, it is important to immediately contact your doctor or go to an emergency
room. Sometimes a blood test, known as d-dimer is done to see if you have a
blood clot. It is considered a good, but not perfect screening test. A positive
result in a patient whom the doctor expects has a DVT is a strong indication
that a clot is present. However, a negative test in a patient that the doctor
has a strong suspicion of DVT is not enough to rule out that diagnosis. The
best test to determine if a DVT is present is a venous ultrasound. Venous
ultrasound, sometimes know as a venous duplex, looks at the blood flow and
appearance of the veins. If blood flow is blocked, a clot exists. Venous duplex
is over 95% accurate in the detection of DVT.
Recently, I had a patient
come to see me in my office for a same day, urgent appointment. She had been
having leg pain and swelling for ten days. I performed an ultrasound in my
office and was able to diagnose a DVT in under 15 minutes with this
non-invasive technique. I was able to talk with her primary care doctor and
coordinate her treatment. She was lucky that she sought medical attention,
before she experienced a life threatening pulmonary embolus, or PE.
How is DVT treated?
The standard treatment for
DVT is anticoagulation (thinning of the blood in layman’s terms) with the use
of a drug called heparin. Heparin prevents the blood clot from getting larger,
but it does not destroy the clot that is there. In the past, all patients were
admitted to the hospital and heparin was given through an intravenous catheter
for about one week. There are new forms of heparin that patients can take just
once or twice a day as an injection just under the skin, very much like
insulin, allowing treatment as an outpatient. Following heparin therapy, a pill
called warfarin or other newer non-vitamin K dependent anticoagulants is started, to further prevent the spread of the clot.
Treatments last typically for 6 months to 1 year. For patients with very
extensive DVT, clot-busting drugs similar to what is used for a heart attack or
brain attack can be used to destroy the clot. This would be followed by
anticoagulation with heparin and warfarin.
Sometimes, patients have medical conditions that prevent them from being
anticoagulated with drugs. In those situations, a medical device called a vena
cava filter can be placed in the inferior vena cava (the large vein in the
abdomen that collects the blood from your legs) to trap a blood clot
travelling.
Rarely, surgery by a
Vascular Surgeon is required to save a leg that DVT has threatened. In 15 yrs,
I have only had to perform limb saving surgery 3x for DVT. In those situations,
the blood clot had spread throughout all the major veins of the leg, and blood
could not get back to the heart. There was no room in the leg for new blood to
enter by the arteries. In surgery, the clot was removed with catheters allowing
blood to return to the heart and supply the leg.
How is DVT prevented?
Ask your doctor to assess
your risk at your annual check-up. For some patients, preventative blood
thinners are needed. For others, just wearing compression stockings or socks is
enough. If you had a DVT in the past, it is important for your doctor to try to
find out why the DVT happened in the first place, and see if your risk factors
can be modified to make it less likely to happen again.
