Published in UAB Insight, Summer 2008
Early, Aggressive Treatment Provides Optimal Results
Deep vein thrombosis (DVT) occurs in more than 250,000 US patients a year with estimated direct medical costs of $300 million. Standard medical management with systemic anticoagulation aims to prevent clot progression of the clot and pulmonary embolism, which carries a 13% in-hospital mortality rate. Elastic compression stockings reduce the risk of postthrombotic syndrome (PTS), but many DVT patients develop chronic complications.
"Anticoagulation alone insufficiently addresses long-term sequelae of DVT," says UAB vascular surgeon Steven M. Taylor, MD. Anticoagulation therapy typically only results in partial thrombus clearance and usually results in venous valvular incompetents, he says. Individuals may develop chronic PTS and recurrent venous thromboembolism. "Patients may have multisegment valvular incompetence, chronic deep venous insufficiency, painful leg swelling, and venous ulceration and claudication," Taylor says.
Thrombus Removal
Thrombus removal has the potential for avoiding such chronic complications. Venous thrombectomy is often indicated in symptomatic patients with severe DVT resulting in a threatened limb and is preferred for those with a contraindication to thrombolysis. Contraindication for thrombolytic therapy includes patients such as those with history of recent abdominal or vascular surgery, stroke, intracranial hemorrhage, malignancy, or surgery.
However, in selected patients with iliofemoral DVT, increasing evidence indicates catheter-directed thrombolysis (CDT) and subsequent anticoagulation therapy produce optimal outcomes (J Vasc Interv Radiol. 2006;17:1099-1104) and (Am J Surg. 2006;192:782-788). Vascular surgeon Marc A. Passman, MD, director of UAB's Vein Program, says, "Catheter-directed thrombolysis and pharmacomechanical clot-
removal techniques are recommended in the new American College of Chest Physicians Antithrombotic Guidelines, issued in June 2008." (Chest. 2008;133:71-109.)
UAB vascular surgeons use an infusion catheter to deliver a tissue plasminogen activator directly into the venous thrombus, dissolving the clot. Most patients require between 24 and 48 hours of infusion. After the patient receives an initial overnight infusion, Taylor checks the extent of lysis on venogram. When necessary, he macerates the clot with a percutaneous thrombectomy device. "Complementary pharmacomechanical techniques are increasingly helpful for management of extensive venous thrombosis," he says.
After a significant amount of lysis occurs, vascular surgeons evaluate the underlying vein and determine if adjunctive therapy, such as venoplasty or stenting, is necessary to address venous stenosis or lesions. Patients are hospitalized for 2 to 3 days and require 6 to 8 months of anticoagulation therapy.
The earlier the thrombus is treated after onset of acute DVT the better the outcomes, Taylor says, "but many patients are not referred until after several months of anticoagulation. The optimal treatment window is 14 days. After 2 weeks effectiveness of thrombolysis significantly decreases." Early, aggressive therapy with CDT can give patients with iliofemoral DVT immediate relief from swelling and pain, prevents tissue loss and valvular incompetence, spares patients PTS, and decreases overall morbidity of severe long-term DVT, Taylor says.
FOR MORE INFORMATION:
Dr. Steven Taylor
1.800.UAB.MIST
mist@uabmc.edu