IVC Filter Placement Declined After FDA Warning: Study

Following FDA warnings about the risk serious complications with inferior vena cava (IVC) filters, where the small devices designed to catch blood clots may migrate or fracture, new research suggests that the medical community quickly began to move away from use of the devices. 

IVC filters are small, spider like devices that have been approved for use among individuals at risk of suffering a pulmonary embolism. While they are designed to catch blood clots that break free elsewhere in the body, and prevent them from reaching the lungs, thousands of individuals have experienced IVC filter injuries, typically involving devices that were designed to be retrievable after the blood clot risk had passed.

In a letter published this week in the medical journal JAMA Internal Medicine, researchers note that years of increasing use of IVC filters is trending down, correlating with an increase in concerns about their safety.

The findings suggest that doctors are being more selective about when to recommend use of IVC filters, following warnings and safety statements released by the FDA in recent years.

The letter was written by researchers from the Washington University School of Medicine in St. Louis, Missouri, noting that the use of IVC filters steadily increased from 1979, when there were 2,000 procedures, to 2005, when the number of implantations per year had grown to more than 104,000.

The study looked at the trend from 2005 to 2014, and used discharge data for adults from the Nationwide Inpatient Sample, the Healthcare Cost and Utilization Project, and the Agency for Healthcare Research and Quality. The researchers looked at not only the raw numbers, but why the filters were placed, which included indications such as venous thromboembolism (VTE), deep vein thrombosis (DVT), pulmonary embolism (PE), and filter placement by contraindication to anticoagulation.

According to the findings, in 2005 there were 322.1 filter placements per 100,000 hospitalizations. That continued upward until 2010, hitting a peak of 412 placements. That number then began to go down in 2010, dropping to 374.1 in 2011, and continuing downward to 321.8 in 2014.

In addition, the percentage of filter placements for prophylactic, or preventative, reasons has become smaller in recent years, the study found, from representing 28.9% of all IVC filter placements in 2005, to 22.6% by 2014.

The 2010 turning point is important, because in August 2010, the FDA reported that it had received more than 900 adverse event reports involving problems with IVC filters, including 328 instances where the filter broke free and migrated through the body, 146 incidents where components broke free, 70 where the filter perforated the vena cava and 56 reports where the filters fractured. At the time, the agency indicated that doctors should consider removing the filters, which were often being left in place even though they are designed to be retrievable.

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, since the risk of problems appeared to be greater the longer the filter was left in place. However, many manufacturers sold the devices for years without adequately informing physicians about the risks associated with leaving them in place.

“Prior studies documented an increase in the rates of IVC filter placement from 1979 to 2005,” the researchers concluded. “Our analysis shows that this trend continued until 2010 when, in a reversal of a 31-year trend, the rates declined from 2011 through 2014.”

They note that their findings are supported by at least one previous study which linked the decrease to the FDA warning.

IVC Filter Lawsuits

In addition to potentially decreasing the use of IVC filters, the FDA warning also sparked off massive litigation against the manufacturers.

There are currently more than 1,800 Bard IVC filter lawsuits pending throughout the federal court system, which are currently centralized before one judge for coordinated pretrial proceedings as part of an MDL, or multidistrict litigation. Another 1,900 Cook IVC filter lawsuits are centralized as part of a separate MDL, raising similar allegations of problems associated with filters manufactured by Cook Medical.

As IVC filter injury lawyers continue to review and file additional claims over the coming months and years, it is ultimately expected that the size of the litigation will continue to grow.

In each MDL, a small group of “bellwether” cases are being prepared for early trial dates, which are designed to help gauge how juries may respond to certain evidence and testimony that is likely to be repeated throughout the litigation. While the outcomes of these early trials will not be binding on other plaintiffs, they may influence eventual IVC filter settlements the manufacturers may reach to avoid facing hundreds of individual trials nationwide.