Deep vein thrombosis (DVT) is a frequently encountered medical condition with about 1 in 1,000 adults diagnosed annually.1,2 Up to one-half of patients who receive a diagnosis will experience long-term complications in the affected limb.1 Anticoagulation is the treatment of choice for DVT in the absence of any contraindications.3 Thrombolytic therapies (eg, systemic thrombolysis, catheter-directed thrombolysis with or without thrombectomy) historically have been reserved for patients who present with phlegmasia cerulea dolens (PCD), a severe condition involving venous obstruction within the extremities that causes impaired arterial blood supply and cyanosis that can lead to limb loss and death.4
The role of thrombolytic therapy is less clear in patients without PCD who present with extensive or symptomatic lower extremity DVT that causes significant pain, edema, and functional disability. Proximal lower extremity DVT (thrombus above the knee and above the popliteal vein) and particularly those involving the iliac or common femoral vein (ie, iliofemoral DVT) carry a significant risk of recurrent thromboembolism as well as postthrombotic syndrome (PTS), a complication of DVT resulting in chronic leg pain, edema, skin discoloration, and venous ulcers.5There is a lack of established standards of care for treating severely symptomatic or extensive proximal DVT without PCD. There are currently no specific treatment recommendations in the major guidelines for this subset of patients.
The goal of thrombolytic therapy is to prevent thrombus propagation, recurrent thromboembolism, and PTS, in addition to providing more rapid pain relief and improvement in limb function. Catheter-directed thrombolysis is preferred over systemic thrombolysis when used for DVT treatment because it is associated with less major bleeding complications and noninferior clinical outcomes.6 Catheter-directed thrombolysis is a minimally invasive endovascular treatment using a wire catheter combination to traverse the thrombus under fluoroscopic guidance through which a thrombolytic drug is infused over a specified duration (usually 24 to 72 hours).7
Catheter-directed thrombolysis can be combined with catheter-directed thrombectomy using the same endovascular technique. This combination is called a pharmacomechanical thrombectomy or a pharmacomechanical thromobolysis and can offer more rapid removal of thrombus and decreased infusion times of thrombolytic drug.8 Pharmacomechanical thrombolysis is a relatively new technique, so the choice of thrombolytic therapy will depend on procedural expertise and resource availability. Early interventional radiology consultation (or vascular surgery in some centers) can assist in determining appropriate candidates for thrombolytic therapies. Here we present 2 cases of extensive symptomatic DVT successfully treated with catheter-directed pharmacomechanical thrombolysis.
Case 1
A 61-year-old male current smoker with a history of obesity and hypertension presented to the West Los Angeles Veterans Affairs Medical Center emergency department (ED) with 2 days of progressive pain and swelling in the right lower extremity (RLE) after sustaining a calf injury the preceding week. The patient rated pain as 9 on a 10-point scale and reported no other symptoms. He reported no prior history of venous thromboembolism (VTE) or family history of thrombophilia.
A physical examination was notable for stable vital signs and normal cardiopulmonary examination. There was extensive RLE edema below the knee with tenderness to palpation and shiny taut skin. The neurovascular examination of the RLE was normal. Laboratory studies were notable only for a mild leukocytosis. Compression ultrasound with Doppler of the RLE demonstrated an acute thrombus of the right femoral vein extending to the popliteal vein.
The patient was prescribed enoxaparin 90 mg every 12 hours for anticoagulation. After 36 hours of anticoagulation, he continued to experience severe RLE pain and swelling limiting ambulation. Interventional radiology was consulted, and catheter-directed pharmacomechanical thrombolysis of the RLE was pursued given the persistence of significant symptoms. Intraprocedure venogram demonstrated thrombi filling the entirety of the right femoral and popliteal veins (Figure 1A). This was treated with catheter-directed pulse-spray thrombolysis with 12 mg of tissue plasminogen activator (tPA).
