What is the management for an extensive left leg Deep Vein Thrombosis (DVT) and an Arteriovenous (AV) fistula at the left mid femoral vein?

Management of Extensive Left Leg DVT with AV Fistula at Left Mid Femoral Vein

The management of extensive left leg DVT with an AV fistula at the left mid femoral vein should include immediate anticoagulation therapy, with consideration for catheter-directed thrombolysis (CDT) or pharmacomechanical catheter-directed thrombolysis (PCDT) followed by stent placement to address both the DVT and AV fistula. 1

Initial Management

• Begin immediate anticoagulation with one of the following regimens:

  • Intravenous unfractionated heparin (UFH) with initial bolus of 80 U/kg followed by continuous infusion at 18 U/kg/hr, adjusted to target aPTT corresponding to anti-factor Xa activity of 0.3-0.7 IU/mL 1
  • Low molecular weight heparin (LMWH) such as enoxaparin 1 mg/kg twice daily or 1.5 mg/kg once daily 1
  • Fondaparinux subcutaneously once daily (5 mg if <50 kg, 7.5 mg if 50-100 kg, 10 mg if >100 kg) 1

• Evaluate for catheter-directed thrombolysis (CDT) or pharmacomechanical catheter-directed thrombolysis (PCDT) as these interventions are reasonable for extensive iliofemoral DVT to prevent post-thrombotic syndrome (PTS) in patients at low risk of bleeding 1

Management of AV Fistula

• The presence of an AV fistula at the mid femoral vein requires specific intervention beyond standard DVT management 2
• Endovascular intervention with stent-graft deployment is recommended to close the arteriovenous fistula 2
• Consider transfer to a center with endovascular expertise if such capabilities are not available at the current facility 1

Endovascular Intervention

• CDT or PCDT is reasonable as first-line treatment for this extensive iliofemoral DVT to prevent post-thrombotic syndrome 1
• During the endovascular procedure:
  • Address the AV fistula with stent-graft placement 2
  • Treat any underlying venous obstructive lesions (such as May-Thurner syndrome if present) with venous stenting 1
  • Consider iliac vein stenting if there is evidence of iliac vein compression or obstruction 1

Long-term Anticoagulation

• Following initial management, transition to long-term anticoagulation:

  • Oral anticoagulation with warfarin (target INR 2.0-3.0) overlapped with initial anticoagulant for minimum 5 days and until INR >2.0 for at least 24 hours 1
  • Direct oral anticoagulants (DOACs) may be considered as an alternative to warfarin 3
  • For patients with cancer-associated thrombosis, LMWH monotherapy is preferred for at least 3-6 months 1

• Duration of anticoagulation:

  • For provoked DVT related to a major reversible risk factor: 3 months 1
  • For unprovoked or recurrent DVT: consider indefinite anticoagulation with periodic reassessment of risk and benefit 1
  • For cancer-related DVT: continue as long as cancer is active or treatment ongoing 1

Prevention of Post-thrombotic Syndrome

• Consider graduated compression stockings (30-40 mmHg) for symptom relief, though recent evidence suggests they may not prevent PTS 1, 3
• Regular follow-up to monitor for signs of post-thrombotic syndrome 3

Special Considerations

• If the patient has limb-threatening circulatory compromise (phlegmasia cerulea dolens), urgent CDT or PCDT is indicated 1
• Consider IVC filter placement only if there are contraindications to anticoagulation or failure of anticoagulation with recurrent PE 1
• Surgical venous thrombectomy may be considered in patients with contraindications to or failure of CDT/PCDT 1

Follow-up Care

• Regular clinical follow-up to assess treatment response and monitor for complications 3
• Duplex ultrasound to evaluate venous patency and stent function 1
• Long-term monitoring for recurrent thrombosis, especially if the AV fistula was traumatic in origin 2

This management approach addresses both the extensive DVT and the AV fistula, with the goal of preventing post-thrombotic syndrome, pulmonary embolism, and long-term morbidity.