Where to refer patients with chronic Deep Vein Thrombosis (DVT)?

Referral Pathways for Patients with Chronic DVT

Patients with chronic DVT (>21 days) should generally be managed in the outpatient setting with continued anticoagulation and compression therapy, but specific subgroups require referral to specialized centers with vascular medicine or interventional expertise. 1, 2

Patients Requiring Specialized Referral

Immediate Referral to Interventional Centers

• Patients with limb-threatening chronic DVT (phlegmasia cerulea dolens) require urgent transfer to centers with catheter-directed thrombolysis (CDT) or pharmacomechanical CDT (PCDT) expertise, even though these interventions are typically contraindicated after 21 days 1, 2

• Young patients with extensive iliofemoral DVT and low bleeding risk who present with severe, persistent symptoms despite anticoagulation should be considered for transfer to centers offering advanced endovascular interventions 1, 3, 2

• Patients at centers lacking endovascular thrombolysis capabilities should be transferred if indications for intervention are present, particularly for rapidly extending thrombus despite adequate anticoagulation 1, 3

Referral to Vascular Medicine Specialists

• Patients with suspected post-thrombotic syndrome (pain, swelling, skin changes, venous ulceration) benefit from referral to vascular medicine specialists for assessment of venous patency, valvular reflux, and consideration of percutaneous transluminal venous angioplasty with stent placement 1, 3

• Patients with iliac vein compression syndrome (May-Thurner syndrome) identified on imaging require vascular specialist evaluation for potential stent placement, as this anatomical variant is commonly associated with left-sided iliofemoral DVT 1

• Patients requiring surgical venous thrombectomy should be referred to experienced vascular surgeons, particularly when there are contraindications to or failure of endovascular approaches 1

Referral to Hematology/Thrombosis Specialists

• Patients with recurrent DVT require hematology referral for thrombophilia workup and determination of indefinite anticoagulation need 1, 4

• Patients with unprovoked (idiopathic) chronic DVT benefit from thrombosis specialist consultation to guide duration of anticoagulation (minimum 6-12 months, often indefinite) and assess for underlying thrombophilic conditions 1, 4

• Patients with chronic DVT provoked by persistent risk factors (inflammatory bowel disease, autoimmune disease, active cancer) require specialist input for indefinite anticoagulation management 1

• Cancer-associated chronic DVT requires oncology-hematology co-management, as these patients need low-molecular-weight heparin (LMWH) monotherapy for at least 3-6 months or as long as cancer treatment continues 3, 2

Patients Suitable for Primary Care Management

• Patients with chronic DVT on stable anticoagulation without complications can be managed in primary care with regular monitoring for medication adherence, bleeding complications, and post-thrombotic syndrome symptoms 3, 2

• Patients requiring only compression therapy optimization (30-40 mm Hg knee-high graduated elastic compression stockings for at least 2 years) can be managed without specialist referral 1, 3

Common Pitfalls to Avoid

• Do not routinely offer CDT or PCDT to patients with chronic DVT symptoms (>21 days), as these interventions are contraindicated in most cases due to lack of efficacy and increased bleeding risk 1

• Do not fail to assess for post-thrombotic syndrome, which affects up to 47% of DVT patients without compression therapy and requires specialist management 3

• Do not overlook the need for indefinite anticoagulation in patients with recurrent or unprovoked DVT, as premature discontinuation significantly increases recurrence risk 1, 4

• Avoid routine placement of inferior vena cava filters, as they do not reduce pulmonary embolism but significantly increase recurrent DVT risk (20.8% versus 11.6%) 3

Special Populations Requiring Coordinated Care

• Pregnant patients with chronic DVT require obstetric-hematology co-management with LMWH therapy throughout pregnancy and postpartum 3, 2

• Patients with high bleeding risk (active bleeding, thrombocytopenia <50,000/mcL, recent surgery, hepatic failure) require hematology consultation for modified anticoagulation strategies 2

• Patients with poor medication compliance or inability to afford anticoagulation may benefit from social work referral and consideration of alternative management strategies including closer monitoring 2