High-risk features of distal deep vein thrombosis
| Severe symptoms (severe pain, throbbing pain when standing that improves with leg elevation, leg discoloration, swelling of the entire limb) |
| Extensive thrombosis (> 5 cm in length, involving multiple veins, > 7 mm in diameter) |
| Thrombosis close to the proximal veins |
| No reversible provoking factor (ie, no transient or persistent risk factor up to 3 months before venous thromboembolic event) |
| Active cancer (newly diagnosed cancer or cancer being treated with surgery, chemotherapy, radiotherapy, hormonal therapy, support therapy for terminal cancer, or combined treatments) |
| History of venous thromboembolism |
| Prolonged immobility (> 3 days) |
| Patient currently has COVID-19 infection |
Based on information in references 1, 7–9.