Retrieval of IVC Filters Usually Successful with Minimal Complications: Study

The findings of a new study suggest that retrievable inferior vena cava (IVC) filters, which are used to prevent blood clots from traveling to the heart and lungs, can usually be removed from patients with few or no complications. The study comes at a time of increased concerns over the risk of IVC filter complications, which may be more likely to occur when the devices are left in place longer.

IVC filters are small, spider-like devices implanted into the inferior vena cava to “catch” blood clots that may break free from the deep veins of the arms or legs. The devices are typically implanted in individuals at risk for pulmonary embolism where anticoagulants have proven ineffective or are contraindicated.

In recent years, questions have emerged about the effectiveness and safety of IVC, with hundreds of adverse event reports suggesting that the devices moved out of position, punctured the vena cava or fractured, causing tiny pieces to travel to the heart or lungs. As a result, federal regulators have warned doctors about the importance of removing the devices as soon as the blood clot risk has passed.

In a study published in this month’s issue of the medical journal Vascular, researchers detail the effectiveness of IVC filter retrieval among doctors from the University of Toledo Medical Center’s Division of Vascular and Endovascular Surgery, finding that the hospital’s doctors were able to successfully remove IVC filters 95% of the time such a removal was attempted.

The researchers looked at data on 484 IVC filter patients from July 2007 through August 2011, of whom 258 had complete medical records. Of those, 96, or 37.2% had permanently placed filters. Another 40, or 15.5%, had temporary filters converted into permanent ones.

According to the findings, 10% of those patients died, and doctors attempted to remove filters from 73 of them, or 28.2%. They were successful in removing 69 of the filters, a success rate of 94.5%. They were unable to retrieve four of them. The most frequent reason they could not be removed was because the IVC filter had tilted out of position, according to the findings.

A letter published in June in JAMA Internal Medicine indicated that researchers from Northwestern University’s Feinberg School of Medicine had an 83% success rate in IVC filter retrieval from January 2009 to December  2014.

Retrievable IVC Filter Risks

Retrievable IVC filters have been introduced in recent years, which allow the surgeon to remove the device once the risk of a clot has passed. However, the filters are often left in place for long periods of time.

In August 2010, the FDA issued an alert about the risk of problems with removable IVC filters, indicating that the agency had received more than 900 adverse event reports at that time. 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.

A study published in the medical journal JAMA Internal Medicine in March 2013 raised questions about the effectiveness of IVC filters, indicating that less than 10% of filters evaluated in the study were successfully removed from patients and 8% of recipients of IVC filters suffered a pulmonary embolism despite the device’s presence.

Following reports of IVC filters failing, with the struts or legs fracturing or puncturing the vena cava, the FDA issued a warning in May 2014, urging doctors to remove IVC filters within about one to two months after the risk of a pulmonary embolism has passed.

Hundreds of individuals who have experienced complications are now pursuing a Bard G2 filter lawsuit, Bard Recovery filter lawsuit or Cook IVC filter lawsuit, alleging that manufacturers sold defective and unreasonably dangerous devices, and withheld warnings about the risk of failure.

Last month, the U.S. Judicial Panel on Multidistrict Litigation (JPML) ordered all Bard IVC filter lawsuits centralized before one judge in Arizona federal court to prevent duplicate discovery, avoid conflicting rulings and serve the convenience of the court, witnesses and both parties.

In October 2014, the U.S. JPML granted a similar request to centralize all Cook IVC filter lawsuits, which raised nearly identical allegations over other brands. The Cook litigation is currently centralized before U.S. District Judge Richard L. Young in the Southern District of Indiana.