Clinical question: Does therapeutic anticoagulation of isolated calf deep vein thrombosis (DVT) decrease risk for proximal DVT or PE?
Background: Optimal management of isolated calf DVT lacks consensus.
Study design: Single-center, retrospective, cohort study.
Setting: Large academic hospital.
Synopsis: Researchers evaluated 14,056 lower-extremity venous duplex studies and identified 243 patients with an intent to treat with therapeutic anticoagulation as well as 141 patients without anticoagulation. The primary outcome was radiographic confirmation of proximal DVT or PE within 180 days of initial study. Duration of anticoagulation, timing of radiographic follow-up, and frequency of follow-up within the first 180 days were varied.
Nevertheless, 9.2% of control patients and 3.3% of exposure patients developed a proximal DVT or PE. The anticoagulation group was associated with lower likelihood of proximal DVT or PE (risk ratio 0.36; 95% CI, 0.15-0.84) but an increased risk of bleeding (8.6%), compared with the nonexposure group (2.2%). Sensitivity analysis did not alter the observed association.
Bottom line: Therapeutic anticoagulation for isolated calf DVT may be warranted to decrease the risk for proximal DVT or PE but with an increased risk of bleeding. Randomized trials are needed to clarify the risk versus benefit.
Citation: Utter GH, Dhillon TS, Salcedo ES, et al. Therapeutic anticoagulation for isolated calf deep vein thrombosis. JAMA Surg. 2016;151(9):e161770. doi: 10.1001/jamasurg.2016.1770.
Dr. Zuleta is an assistant professor and associate program director of the Jackson Memorial/University of Miami Internal Medicine residency training program and the site director of the program at University of Miami Hospital.