Table 1. Risk Factors for Extension (2-C) Positive D-dimer
Thrombosis that is extensive or close to the proximal veins (eg, > 5 cm in length, involves multiple veins, > 7 mm in maximum diameter) No reversible provoking factor for DVT Active cancer History of VTE Inpatient status
Acute Leg DVT Confirmed isolated distal DVT
Symptoms severe Extension risk
Symptoms not severe No extension risk
Serial imaging x 2 wks Thrombus extension
If bleed risk resolves
Confirmed proximal DVT Bleed risk IVC filter
VKA x ≥ 5d and INR ≥ 2.0 x > 24h
Compression ockings
Surgical or other transient factor Unprovoked Active cancer
AND LMWH daily or fondaparinux (or IV or subcut UFH)
ambulation Early
Duration of Anticoagulation for LE DVT 3 months
≥ 3 months ≥ 3 months
3
