PE recurrence same with vena cava filter plus anticoagulation as anticoagulation alone

Adding an inferior vena cava filter did not reduce the risk of recurrent pulmonary embolism (PE) compared to anticoagulation alone, according to a recent study of French patients hospitalized with PE.

The open-label trial included patients who were hospitalized with acute, symptomatic PE associated with lower-limb venous thrombosis and who met at least 1 criterion for severity between 2006 and 2012. The patients were randomized to retrievable inferior vena cava filter implantation plus anticoagulation (n=200) or anticoagulation alone (n=199) and were followed for 6 months. Patients with a contraindication to anticoagulation therapy and those with recurrence despite adequate anticoagulation were excluded. Results were published in the April 28 Journal of the American Medical Association. 

Filters were successfully inserted in 193 patients, and they were retrieved, at 3 months after placement, in 153 of the 164 patients in whom retrieval was attempted. By 3 months, 6 patients in the filter group had a recurrent PE (3.0% of the group, all were fatal), compared to 3 patients in the anticoagulation-only group (1.5% of the group; 2 fatal; P=0.50 for PE recurrence). The groups also had similar rates of recurrence within 6 months, symptomatic deep venous thrombosis, major bleeding, and mortality within 3 or 6 months. Filter thrombosis occurred in 3 patients. One patient died of cardiac arrest during filter insertion.

Implantation of the filters did not reduce risk of symptomatic PE recurrence, and thus the study's results do not support use of inferior vena cava filters in PE patients who can be treated with anticoagulation, the study authors concluded. The rate of PE recurrence in the study was less than expected, but this shows that "modern management with full-dose anticoagulation is likely very effective even in patients usually considered to be at high risk for recurrence," the authors wrote.

The study was limited by its open-label design and its small size, and the results do not exclude the possibility of benefit from filters in certain subgroups of patients with venous thromboembolism, such as those with PE and hemodynamic instability. The study used the ALN brand of filter (provided by the manufacturer for the study), but given existing evidence of similarities among retrievable filter models, the results are probably applicable to other retrievable filters, the authors said.