For tens of thousands of Americans, the inferior vena cava (IVC) filter has literally been a lifesaver. This spider-like device is designed to stop blood clots before they reach the lungs, reducing the risk of a life-threatening heart attack, stroke, or deep vein thrombosis.
Unfortunately, the use of these filters has come with serious complications. The U.S. Food and Drug Administration (FDA) has received tens of thousands of complaints about these filters, and more than 10,000 lawsuits against the two main IVC filter manufacturers are pending in federal and state courts throughout the country.
Learn more about the development and use of IVC filters, as well as some of the most prevalent IVC filter complications and how some injured plaintiffs are fighting back.
What IVC Filters Are and How They’re Used
IVC filters are incredibly small—designed to fit inside a heart vessel—and resemble a hand-held scalp massager. These filters are most commonly used in patients with a condition known as venous thromboembolism (VTE).
VTE involves a deep vein thrombosis (DVT)—or a blood clot that forms in the “deep veins” of the groin, arm, or leg—that travels through the body’s circulatory system, ultimately winding up in the lungs. Although a blood clot in any part of the body is risky, a blood clot that reaches the lungs can quickly become life-threatening. These clots can prevent your lungs from oxygenating your blood and your heart from circulating blood through your body. This condition can lead to a stroke, heart attack, or cardiac arrest.
For many patients with VTE, this condition can be managed or even cured through the use of prescription blood thinners like warfarin. These blood thinners break down the platelets that cause clotting and reduce the risk that a blood clot will reach the heart or lungs before it breaks apart on its own.
But warfarin and other blood thinners aren’t safe for everyone. For example, those who are scheduled for an invasive operation may not be able to take blood thinners due to the risk of hemorrhage during surgery. For those who are at high risk for a VTE recurrence, an IVC filter can protect the lungs from wayward blood clots.
Today’s IVC filters are designed to be retrievable, which seems a likely contributing factor to the rising number of IVC filter placements in the U.S. After all, if an IVC filter can reduce one’s risk of VTE and be removed if complications develop, what’s the harm? But only about one in three IVC filters are ever removed, which means that for many, this temporary solution may become a permanent fixture in one’s body. Furthermore, some IVC filters can’t be removed, even if the patient requests it.
The Problems With IVC Filters
Some IVC filter side effects are mild (and outweighed by the benefit of the device), but others can be serious or even life-threatening. Just a few of the potential complications of IVC filter use include:
IVC Filter Migration
Once implanted, an IVC filter is designed to stay in one place until it is removed. Unfortunately, this doesn’t always happen, and an IVC filter that decides to go rogue can become lodged just about anywhere in the body. Because IVC filters are so close to the heart, the force of the blood being pumped through the veins can push these filters quite a way through the bloodstream once they’ve become dislodged.
IVC Filter Perforation
An IVC filter that migrates through the bloodstream can perforate tissues or even organs, leading to internal injuries. Of the IVC perforations reported to the FDA, about 13 percent involved a bowel perforation, while nearly seven percent involved perforation of the aorta. Depending on the degree of penetration, the location of the IVC filter in the body, and the medications the patient is taking, an IVC filter perforation can range from symptom-free to incredibly painful.
Although IVC filters have a much higher success rate than blood thinners when it comes to preventing recurrent DVT in the two weeks following filter placement, over the long term, studies have indicated that they actually increase the risk of recurrent DVT.
Up to 12 days after an IVC filter has been placed, the risk that a DVT-generated clot will reach the lungs is only 1 percent (compared to nearly 5 percent for patients using blood thinners). But two years after the IVC filter has been placed, a patient who is not on blood thinners and is relying only on the IVC filter is 10 percent more likely to experience another DVT.
IVC Filter Fracture
If a portion of the IVC filter breaks off, not only does it diminish the effectiveness of the filter, it increases the risk of soft tissue or organ perforation, heart attack, and stroke. With so many retrievable IVC filters becoming permanent, filter fracture rates are increasing. In fact, some studies have indicated that the risk of IVC filter fracture can be as high as 40 percent after five years.
Vena Cava Thrombosis
Thrombosis of the inferior vena cava is a counterintuitive complication of an IVC filter—this thrombosis (or blood clot formation) actually occurs at the site of the IVC filter itself. Even when an IVC filter might be effective at removing a blood clot that’s traveling through the bloodstream, these filters are far less effective at stopping blood clots that form around or behind them.
IVC Manufacturers Sued
In August 2010, the FDA issued a warning to consumers to remind them that retrievable IVC filters are designed for short-term use only. Three years later, it followed this warning up with a decision analysis in the Journal of Vascular Surgery; the same year, the Journal of the American Medical Association (JAMA) published a study pointing out the filter’s high failure and complication rate. Later in 2013, the FDA recalled around 33,000 Cordis-branded retrievable IVC filters, alleging that the device’s labeling and implant instructions were faulty.
Unfortunately for many patients, the number of IVC filters that were placed and never removed continued to increase. In 2015, the FDA issued a warning letter to C.R. Bard after learning that the manufacturer was marketing an IVC removal system without FDA clearance or approval. And in 2016, the American College of Cardiology published a study that concluded doctors were continuing to deploy IVC filters for a wide range of medical purposes, even though these off-label uses hadn’t been thoroughly studied.
It’s not clear when or where the very first IVC filter lawsuit was filed, but multi-district litigation against the two main manufacturers of IVC filters—Cook Medical and Bard—was launched in 2014 and 2015, respectively. The litigation against Cook is proceeding in the Southern District of Indiana, while the litigation against Bard has been consolidated in an Arizona District Court. Most of the state cases against Cook, Bard, and other manufacturers have been stayed pending the outcome of the federal multi-district litigation.
Although each IVC filter lawsuit has its own unique facts, multi-district litigation (or MDL) is designed to ensure that results are generally consistent among similar classes of plaintiffs. MDL also conserves judicial resources by preventing courts from having to try thousands of cases that revolve around a single theory of harm against a single defendant.
To achieve these goals, the MDL parties choose one or more cases that are deemed representative: the “bellwether case.” The outcome of the bellwether case can steer the path of the remaining cases. A verdict for the plaintiff that is affirmed on appeal can spur a defendant to settle similar claims; on the other hand, a finding of no liability can make it tougher for other plaintiffs’ cases to proceed.
The Cook Litigation
In the Indiana multi-district litigation, the claims by plaintiffs who have received a Cook Medical IVC filter generally include:
- Defective design;
- Misrepresentation in marketing (including the branding of these IVC filters as retrievable or removable)
- Failure to warn doctors and patients.
In late 2017, the first bellwether trial against Cook Medical ended in Cook’s favor; less than six months later, the second bellwether trial was dismissed as time-barred. But the third Cook bellwether trial resulted in a $3 million jury award in the plaintiff’s favor, although declining the plaintiff’s request for punitive damages.
The Bard Litigation
The claims against C.R. Bard are nearly identical to those against Cook Medical: negligence, failure to warn, defective design, and misrepresentation.
In the first bellwether lawsuit, a jury in Phoenix awarded $1.6 million in compensatory damages and $2 million in punitive damages. The second bellwether lawsuit was decided in Bard’s favor, with the jury determining that Bard provided sufficient product warnings to doctors and other medical professionals. And a third bellwether also went in Bard’s favor, with the District Court finding that the plaintiff’s claim was barred by the statute of limitations.
In October 2018, a jury decided that Bard was not negligent in a case involving a plaintiff whose IVC filter was successfully removed in 2014.
State Court Litigation
In addition to the two main federal MDLs, there are multiple class action lawsuits against Bard proceeding in California, Pennsylvania, Florida, and other state courts. These lawsuits allege state-law causes of action for negligence, misrepresentation, and data concealment, with the plaintiffs (many of whom have IVC filters that had migrated and cannot be removed) seeking compensation to help cover their medical monitoring expenses. In late 2018, a Texas jury awarded $1.2 million against Cook Medical in a failure-to-warn case.
What’s Next for IVC Litigation?
Because of the sheer number of individual lawsuits against Cook, Bard, and other IVC filter manufacturers, as well as the mixed results reached in the first few bellwether cases, more of these “test” trials took place last year. Appeals are pending.
Although additional verdicts in the defendant manufacturers’ favor may weaken the negotiating strength of the remaining lawsuits, plaintiffs may still be able to prevail if they can show two key factors: (1) the manufacturer failed to adhere to the appropriate standard of care; and (2) this breach caused actual physical, emotional, or financial damage to the plaintiff.
Meanwhile, if more of these bellwether cases follow the path of the first Bard case—awarding the plaintiff even more in punitive damages than compensatory damages—it seems likely that a large-scale IVC filter settlement may soon be on the horizon.
Inferior vena cava filters: debatable benefit; rarely removed