Duration of warfarin for first DVT is hotly debated. In this multi-center trial of patients with new first DVT, patients were randomized to fixed-duration or flexible-duration (based on consecutive USG findings at 3 months). The fixed-group received 3 months of warfarin for secondary DVT, and 6 months for unprovoked DVT. The flexible-group received 3 months (if their 3 month USG showed vein re-canalization). For those not re-canalized at 3 months, they received additional USG at 3 and 9 months (for secondary DVT) and at 3, 9, 15, and 21 months (for unprovoked DVT). The 33 month f/u recurrent DVT risk was 12% in the flexible-group, which was significantly lower than the 17% in the fixed group. This indicates an advantage of continuing warfarin in patients without re-canalization. However, an editorialist points out that patients with idiopathic DVT need indefinite warfarin, and those with provoked DVT need “time-limited” warfarin. The latter may be a reasonable group to schedule f/u USG to determine length of warfarin treatment (abstract).
Dr. Scheurer is a clinical hospitalist and the Medical Director of Quality and Safety at the Medical University of South Carolina in Charleston, South Carolina, and is Assistant Professor of Medicine. She is a graduate of the University of Tennessee College of Medicine, completed her residency at Duke University, and completed her Masters in Clinical Research at the Medical University of South Carolina. She also serves as the Web Editor and Physician Advisor for the Society of Hospital Medicine.