Deep Vein Thrombosis

Last summer, Chuck Felts was having flu-like symptoms and they seemed to be worsening. “A couple of days after this started, I was so short of breath that I could not climb a flight of stairs,” he recalls.

A Not So Uncommon Occurrence

By Charlotte Boatwright, R.N., PH.D.

“I went to the emergency room where they determined that I had a pulmonary embolus (blood clot blocking blood flow through the lung) caused by a clot forming in my leg (deep vein thrombosis) that had broken loose and moved to my lung,” says Felts. “By the time I got to the hospital, I had lost about one-third of my lung capacity and was having difficulty breathing.” The pulmonary embolus was treated and dissolved with Heparin, a clot-dissolving medication. Today, Felts takes Coumadin, a blood thinner, to prevent formation of further clots.

More than 2 million Americans are affected by deep vein thrombosis (DVT) each year in the U.S. Approximately 200,000 people die from pulmonary embolus each year. Deep vein thrombosis can occur in almost anyone; however, common risk factors include surgery, a sedentary lifestyle, congestive heart failure, cancer, infectious disease, smoking and obesity.

The week before he developed DVT, Felts recalls that he had a long period of inactivity in his car while driving back from Florida. Then, while working on his tractor, he had his leg wedged under the seat in a position that restricted blood flow for a considerable period of time. “The circulation was slowed in my leg from these activities and a clot formed,” he says. “Over the next week, the clot broke loose and moved to my lungs, so I ended up in the hospital. Apparently you can die from that.”

Felts remembers having a clot once before after a traumatic injury. “It is very important that you follow orders when doctors tell you to get out of bed and move around after surgery or an injury,” he says.

Dr. Ian Hamilton of Comprehensive Vascular Care in Dalton, Georgia, says he sees patients with DVT or superficial venous thrombosis almost weekly, either in the hospital or in the office.

According to Hamilton, the signs and symptoms of DVT can vary, but often include the following: nothing (asymptomatic DVT), mild to massive swelling of the effected extremity, a dark blue or white discoloration of the extremity, pain, edema, local redness, tenderness, fever, prominent veins close to the skin surface, pain in the calf with passive dorsiflexion of the foot, or a combination of several of these.

Dr. Daniel Fisher of University Surgical Associates in Chattanooga says that he sees DVT about once a week in his practice, as well.

“The first sign a patient might see to indicate DVT would be a deep, dull ache in the leg that changes to a sharper, more acute pain on movement,” Fisher notes. “Typically, the pain occurs along the course of the vein with the clot. The leg may swell and there may be redness. The patient should call the family doctor or go to an emergency room to have an ultrasound to diagnose DVT.”

How Clots Form

The circulatory system, made up of the heart, veins and arteries, is responsible for maintaining the flow of oxygen throughout the body to keep tissue alive. Arteries transport newly oxygenated blood from the heart throughout the body. Veins return blood that is low in oxygen back to the heart and lungs for a new oxygen supply. Deep veins in the legs return the blood back to the heart, with assistance from the leg muscles and one-way valves that close to prevent blood from flowing back to the feet. Circulation may be slowed by illness, injury or inactivity, causing pooling and stagnating of the blood in the veins – an ideal setting for clots to form. Risk for clotting can be increased by inactivity, medication or genetics.

Fisher emphasizes that anyone who has undergone recent surgery, is obese, has cancer or a history of a clotting disorder in the family is at greater risk for DVT. “If there is a history of clotting in more than one or two members of a family, they probably need to have the family checked out for clotting disorder,” he says. “That would certainly heighten your suspicion.

“Females with a family history of DVT should avoid taking birth control pills, as women taking estrogen are more prone to clotting,” Fisher says. “About one-third of them will develop DVT. If you know for a fact that you have a history of a clotting disorder in the family, and you want to be on birth control, you need to opt for something other than birth control pills, particularly if you have had a blood test to indicate that you are a carrier of a gene that makes you likely to have a syndrome.”

Treating DVT

Less invasive treatment is usually preferred for treating DVT, from administration of blood-thinning (anticoagulant) or clot-dissolving (thrombolytic) medications to removal of the clot (thrombus) with a mechanical thrombectomy device. Catheter-directed thrombolytic therapy requires the threading of a catheter through the vein and into the clot. Thrombolytic medication is then infused to dissolve the clot.

The Food and Drug Administration recently granted clearance for the use of AngioJet mechanical thrombectomy for DVT. The AngioJet system quickly removes the clot, restores blood flow, and relieves symptoms. A thin, flexible catheter is inserted into the clot. High-speed water jets create a vacuum that pulls the clot into the catheter; the jets break the clot into tiny fragments that are pulled back through the catheter and removed from the body.

Complications from DVT

Several complications can occur after DVT. “There are about six sets of valves in the veins of the legs,” Fisher says. “After you have clots in veins, the valves have scarring that keeps them from working properly. When you stand on your legs, the blood does not return to the heart as it did before. Months after DVT, legs swell and hurt because the blood pools in them.”

Once damaged by DVT, the valves do not ever work exactly the same again. “We put people into stockings to encourage venous return to the heart,” Fisher says. “In the long term, if you don’t wear the stockings, you can get venous stasis ulcers.”

Prevention of DVT

People who remain in a sitting position for long periods of time during the day, such as trucker drivers, are particularly at risk for DVT. Travelers on overseas flights can also be at-risk for DVT, according to Dr. Fisher.

“If there is no contraindication, it is a good idea to take an aspirin before a long flight,” Fisher says. “Like other anticoagulants, aspirin is an antiplatelet agent, which is thought to be more protective of the arteries than of the veins. Though not as specific as Coumadin as an anticoagulant, aspirin is readily available and may prevent the initial formation of a blood clot. Taking an aspirin each day may be a good thing.

“Some doctors are putting all patients over 50 years of age on aspirin, unless there is a reason not to do so, because it appears to prevent many problems, such as heart attack and stroke,” he says. “Most cardiologists that I see have their patients on 81-mg baby aspirin, which may be protective for many things, including DVT.”

Consulting with your doctor and educating yourself about DVT are the best defenses in preventing DVT.

Charlotte Boatwright is a native Chattanoogan. She has a doctorate in health care administration and is a registered nurse and licensed professional counselor. Charlotte has been involved with health care for 35+ years and is the founding member and president of The Coalition Against Domestic & Community Violence of Greater Chattanooga, Inc./ Chattanooga Family Justice Alliance.