April 28th, 2015
No Advantage to Adding Inferior Vena Cava Filters to Anticoagulation
Larry Husten, PHD
Despite a lack of supporting evidence many patients with acute venous thromboembolism (VTE) receive inferior vena cava filters to prevent pulmonary embolism (PE). Now a new study published in JAMA offers no evidence of benefit for the use of these devices in a high-risk population already receiving anticoagulant drugs.
A group of French physicians randomized nearly 400 hospitalized patients with acute, symptomatic PE to receive a retrievable inferior vena cava filter in addition to anticoagulation or anticoagulation alone. At 3 months, recurrent PE had occurred in 6 patients (3%) in the filter group compared with 3 patients (1.5%) in the control group. The two-fold increase in risk with the filter was not statistically significant. All 6 cases in the filter group and 2 of the 3 cases in the control group were fatal. Between three and six months there was one additional case of recurrent PE in each group.
The authors note that the increased use of filters has likely been fueled by the availability of retrievable inferior vena cava filters. Their results show that these devices confer “no benefit in terms of pulmonary embolism recurrence or mortality” in these patients.
Based on previous studies the authors say they had anticipated a much higher rate of recurrent PE, about 8%, in the control group. “We believe that the low rate of events observed in the control group of our study is consistent with contemporary care, indicating that modern management with full-dose anticoagulation therapy is likely very effective even in patients usually considered to be at high risk for recurrence, rendering unnecessary additional therapy such as inferior vena cava filters,” they write. In addition, “we believe that our negative findings likely reflect the low event rate with effective anticoagulation alone rather than lack of filter efficacy.” They note, however, that they excluded patients who were unable to take an anticoagulant or who had a recurrence despite adequate anticoagulation.