IVC Filter to Go Under Microscope, Lawsuits Continue to Settle

Washington, DCIt isn’t quite the same as changing the oil filter on your car. But then again, perhaps there are some similarities: the IVC filter, or inferior vena cava filter, is a tiny device implanted by doctors to “catch” migrating blood clots that have broken away from an arterial wall. In so doing, the IVC filter prevents the blood clot from migrating to the lungs, an event that usually proves disastrous.

However, there are problems with the devices, and various lawsuits have been filed against the two primary manufacturers - Cook Group Inc. and C.R. Bard - alleging the devices are defective. A major post-market study aimed at evaluating the safety and efficacy of the devices launches this year.

The Cook Celect and Gunther Tulip IVC filters are fashioned from metal and are spider-like in appearance. While they have been found to perform well for the indication to which they have been designed, there have been allegations of other problems, including migration and perforation. A study published in 2012 in Cardiovascular Interventional Radiology found that 100 percent of the Cook filters perforated the study participant’s venal wall within 71 days of implantation.

The inferior vena cava filter in 40 percent of study participants was found to have tilted away from its original optimum position for capturing wayward blood clots from the leg.

IVC filters are also designed to be removed once their task is complete. In May of last year, the US Food and Drug Administration (FDA) issued a safety bulletin advocating that the ideal window for device retrieval is from 29 to 54 days after implantation. That said, the FDA was on record, as early as 2010, indicating that an IVC filter should be removed as soon as the danger of a pulmonary embolism had passed.

However, retrieving and removing the devices has also proven to be problematic and has fostered many an IVC filter lawsuit. A study published in JAMA Internal Medicine in March 2013 found that less than 10 percent of filters were successfully removed, with eight percent of IVC patients suffering a pulmonary embolism in spite of having an IVC in place.

In 2010, at the time the FDA issued its cautionary bulletin to doctors, more than 900 reports had flowed into the FDA’s Adverse Events Reporting System (AERS). Common amongst the complaints were the fracturing of devices, allowing small pieces to migrate through the bloodstream and risk potential injury or death.

Many health advocates would like to see an IVC filter recall or ban. But that hasn’t happened, and doesn’t appear to be on the horizon in the foreseeable future. To that end, the so-called PRESERVE Study (Predicting the Safety and Effectiveness of Inferior Vena Cava Filters) will commence this spring and last for five years. Once the multispecialty prospective clinical trial concludes, it will then take time to analyze, vet and publish the research data. The FDA would then study the data, perhaps convene expert panels and consider next steps. Those next steps - assuming the clinical trial extends to its planned completion - could take almost a decade to appear.

As for lawsuits involving the IVC filter, about 32 complaints involving the Cook Celect and Gunther Tulip filters have been filed in various federal courts across the US. Those lawsuits, by order of the US Judicial Panel on Multidistrict Litigation (JPML) are to be consolidated and centralized in the Southern District of Indiana for coordinated pretrial proceedings.

As for C.R. Bard, manufacturer of the Bard G2 IVC filter and the Recovery IVC filter, several hundred lawsuits have been reportedly filed. Allegations are that Bard knew for a period of some years that its IVC filters were prone to fracture, but failed to warn doctors and their patients, or so it is alleged.

The Bard lawsuits were never consolidated, according to reports. Other reports hold that Bard has been quietly settling lawsuits over its Bard G2 filter, although few details of specific lawsuits are available.