1. Duration of Anticoagulation 5 Patients Categories 3. First Episode: 4. First Episode: 5.Recurrent DVT 2. First Episode: 1. First Episode: Transient risk Concurrent cancer Thrombophilia or prognostic marker Idiopathic Deep Vein Thrombosis

2. Patient Category Duration 3 months 6-12 months Consider indefinite 6-12 months Consider indefinite 12 months (consider indefinite) LMWH x 3-6 months Anticoag. Indefinitely or cancer cured LMWH x 3-6 months Anticoag. Indefinitely or cancer cured Transient Idiopathic Cancer Thrombophilia Recurrent DVT Indefinite ACCP CHEST 2004 Deep Vein Thrombosis Duration of Anticoagulation

3. Acute DVT Stopping Anticoagulation Considerations 1.Does patient have persistent venous thrombosis? 2.Is there persistent thrombus activity? ….impact on duration of anticoagulation 1.Does patient have persistent venous thrombosis? 2.Is there persistent thrombus activity? ….impact on duration of anticoagulation

4. Recurrent VTE Residual Venous Thrombus Time after Initial DVT, mo Cumulative Proportion of Patients with Recurrent VTE Prandoni, P et al Ann Intern Med 2002;137:955 Prandoni, P et al Ann Intern Med 2002;137:955

5. Recurrent VTE: Prospective Study Patient Characteristics Thrombophilia Idiopathic Secondary Recurrence @ 2 years Characteristic 15% 7% 4% All 10.3% 4.4% 0% US Normal 23% 7.5% 7.1% US Abnormal Prandoni, P et al Ann Intern Med 2002;137:955 Prandoni, P et al Ann Intern Med 2002;137:955

6. Recurrent VTE D-Dimer Eichinger S et al JAMA 2003; 290: 1071 Eichinger S et al JAMA 2003; 290: 1071 Probability of Recurrence at 3 Years < 250 ng/ml 3.7%* > 250 ng/ml 11.5% P = 0.001 60% lower risk of recurrence*

7. Associated with Severe Postthrombotic Morbidity! O'Donnell TMavor GEBeyth RJ J Surg Res. 1977Br J Surg 1969Arch Int Med 1995 O'Donnell TMavor GEBeyth RJ J Surg Res. 1977Br J Surg 1969Arch Int Med 1995 Iliofemoral DVT Natural History

8. Anticoagulation Long-Term Venous Function 20 patients with iliofemoral DVT Conventional anticoagulation Followed 5 years Long-Term Venous Function 20 patients with iliofemoral DVT Conventional anticoagulation Followed 5 years Akesson H, Eur J Vasc Surg 1990 Iliofemoral DVT

9. Parameter @ 5 yrs Calf Muscle Dysfunction Ambulatory Venous Hypertension Venous Insufficiency Venous Claudication Venous Ulceration Parameter @ 5 yrs Calf Muscle Dysfunction Ambulatory Venous Hypertension Venous Insufficiency Venous Claudication Venous Ulceration % 50% 95% 90% 15% % 50% 95% 90% 15% Iliofemoral DVT Akesson H, Eur J Vasc Surg 1990 Anticoagulation

10. Iliofemoral DVT Rationale for Thrombus Removal A strategy of thrombus removal reduces the risk of postthrombotic syndrome!