Unretrieved IVC Filters Can Lead To Thrombosis Risk: Study

Amid recent concerns about the risk of complications with inferior vena cava (IVC) filters, where the devices designed to prevent blood clots from traveling to the lung have been found to puncture internal organs or fracture inside the body, a new study suggests that retrievable IVC filter designs may actually increase the risk of blood clots when they are left in place for extended periods of time.

In a study published this month in the medical journal JACC Cardiovascular Interventions, researchers from the University of Rochester Medical Center in New York warn that unretrieved IVC filter thrombosis is probably responsible for 2.6% to 4% of all cases of deep vein thrombosis, and that number is likely underreported.

IVC filters are spider-shaped devices inserted into the vena cava to “catch” blood clots that may break free within the body, preventing them from traveling to the lungs and causing a pulmonary embolism.

In recent years, designs have been introduced that allow the filter to be removed once the risk of pulmonary embolism has passed. However, problems with retrievable IVC filters have been linked to thousands of severe and often fatal injuries, where the filter moved out of position, the structs punctured the vein, or broke off, often traveling to the heart or lungs with catastrophic consequences.

In May 2014, the FDA urged doctors to remove IVC filters within about one to two months after an individual was no longer at risk of suffering a pulmonary embolism, and manufacturers have been criticized for failing to adequately warn doctors about the importance of retrieving the device, as the risk of fractures and migrations may increase the longer the filter remains in place.

The findings of this new study raise further concerns, with an unretrieved IVC filter blood clot risk also associated with leaving the devices in place.

The scientific review of the methods of diagnosis, treatment options and etiologies of IVC filter thrombosis, warns that there is limited scientific data on the problem, and researchers indicate that more data needs to be gathered to guide the medical community.

Researchers concluded that patients who have untreated IVC filter blood clots have a 90% chance of suffering post-thrombotic syndrome if the devices are not removed, a 45% chance of disabling venous claudication, a 30% chance of suffering a pulmonary embolism, and a 15% chance of a venous ulceration.

In an accompanying editorial, Dr. Michael R. Jaff, of Massachusetts General Hospital in Boston, said that it may be difficult for doctors to diagnose an IVC filter thrombosis. However, he said the group’s findings, especially with the chance of a failure to diagnose, backs up the FDA’s recommendations to just remove the filters when they are no longer needed. He indicates that the new study highlights a long-hidden and growing problem.

“Of tremendous importance is their recognition that the most common cause of this challenging disorder is thrombosis of previously deployed IVC filters,” Jaff wrote. “With the rapid expansion in placement of IVC filters, particularly in the United States, we can expect this problem to actually increase.”

IVC Filter Lawsuits

Hundreds of Bard G2 filter lawsuits, Bard Recovery filter lawsuits and Cook IVC filter lawsuits have been filed in recent years on behalf of individuals who suffered injuries when these retrievable designs migrated, perforated or fractured.

The litigation first emerged in 2010, after the FDA indicated that more than 900 adverse event reports had been received involving the devices. Of those reports, 328 involved the IVC filter breaking free and migrating through the body, 146 involved  components breaking loose, 70 involved the inferior vena cava being perforated and 56 involved the filter fracturing.

Each of the complaints raise similar allegations that the small devices are unreasonably dangerous, and contain inadequate warnings about the potential risk of problems with IVC filters.

As IVC filter injury lawyers continue to review and file complaints on behalf of individuals who have suffered migration or perforation problems, it is ultimately expected that several thousand cases will be filed against manufacturers of the devices, and it is possible that cases may also be pursued for individuals who suffered blood clots from IVC filters.