Implanting a retrievable filter in the inferior vena cava did not reduce the rate of recurrent pulmonary embolism or mortality in high-risk patients, according to a report published online April 28 in JAMA.
In recent years, there has been a sharp increase in the use of these devices as an add-on to anticoagulant therapy among patients hospitalized for acute PE associated with lower-limb deep or superficial vein thrombosis. Several clinical guidelines advocate this strategy, though others do not, citing the paucity of reliable data concerning both risks and benefits.
The findings in this study “do not support the use of this type of filter in patients who can be treated with anticoagulation alone,” and clinical guidelines recommending this approach should be reexamined, Dr. Patrick Mismetti of the University Hospital of Saint-Etienne, France, and his associates said.
They performed a randomized, open-label clinical study at 17 French medical centers to compare anticoagulation alone against anticoagulation plus implanting a filter to be retrieved 3 months later.
The study participants were 399 adults enrolled during a 6-year period who were deemed at high risk for recurrent PE because of advanced age, active cancer, chronic cardiac or respiratory insufficiency, ischemic stroke with leg paralysis, DVT that was bilateral or affected the iliocaval segment, or signs of right ventricular dysfunction or myocardial injury.
The primary efficacy outcome, recurrent PE within 3 months of hospitalization, developed in 6 of 200 patients assigned to receive an implantable filter (3%) and 3 of the 199 assigned to the control group (1.5%). All but one of these episodes of recurrent PE were fatal. One additional PE developed in each study group between 3 and 6 months. There were no differences between patients who received an inferior vena cava filter and those who did not in the incidence of DVT, major bleeding, or death from any cause at 3 or 6 months, the investigators said (JAMA 2015 April 28 [doi:10.1001/jama.2015.3780]).
Besides failing to prevent recurrent PE, the filter implantation caused access site hematomas in five patients, and the filter itself caused thrombosis formation in three. One patient developed cardiac arrest during the procedure. In addition, retrieval of the device failed in 11 patients because of mechanical problems.