Use of Vena Cava Filter Does Not Reduce Risk of Recurrent Blood Clot for Patients Receiving Anticoagulant

Among hospitalized patients with severe acute pulmonary embolism (a life-threatening blood clot in a lung), the use of a retrievable inferior vena cava filter plus anticoagulation compared with anticoagulation alone did not reduce the risk of recurrent pulmonary embolism or death, according to a study in the April 28 issue of JAMA.

An inferior vena cava (the largest vein in the body) filter is a type of vascular filter that is implanted to prevent blood clots. Observational studies show a sharp increase in the placement of inferior vena cava filters over the past 3 decades, including their use as add-on therapy to anticoagulant therapy in patients presenting with a blood clot. However, due to the lack of reliable data, the benefit vs risk is uncertain, according to background information in the article. 

Patrick Mismetti, M.D., Ph.D., of the Centre Hospitalier Universitaire de Saint-Etienne, France and colleagues randomly assigned hospitalized patients with acute, symptomatic pulmonary embolism associated with lower-limb vein thrombosis and at least 1 criterion for severity to retrievable inferior vena cava filter implantation plus anticoagulation (n = 200) or anticoagulation alone with no filter implantation (control group; n = 199). Initial hospitalization with ambulatory follow-up occurred in 17 French centers; follow-up was 6-months. Filter retrieval was planned at 3 months from placement.

In the filter group, the filter was successfully inserted in 193 patients and was retrieved as planned in 153 of the 164 patients in whom retrieval was attempted. By 3 months, pulmonary embolism had recurred in 6 patients (3.0 percent) in the filter group and 3 patients (1.5 percent) in the control group. All episodes in the filter group and 2 of 3 in the control group were fatal. One additional pulmonary embolism recurrence was observed in each group between 3 and 6 months.

No difference was observed between the 2 treatment groups for deep vein thrombosis, major bleeding, or death from any cause at 3 and 6 months.

“The availability of retrievable inferior vena cava filters has probably contributed to the increasing use of filters for managing acute venous thromboembolism, including their use in addition to full-dose anticoagulant therapy in patients with pulmonary embolism, a large clot burden, a poor cardiopulmonary reserve, or a suspected increased risk for recurrence, as advocated by several guidelines. The results of the present study do not support such a strategy,” the authors write. “These findings do not support the use of this type of filter in patients who can be treated with anticoagulation.”