Cook IVC Filters
In April 2012, scientists published a study in the journal Cardiovascular Interventional Radiology examining the safety of Cook Gunther Tulip and Celect inferior vena cava (IVC) filters. These filters are often implanted in patients at risk of blood clots who cannot take anticoagulant drugs for some reason, or for whom the anticoagulant drugs have not been effective.
Researchers followed-up on 50 patients who received these filters between 2007 and 2009. They found that all filters, after 71 days, showed some degree of perforation into the vena cava vein, and looked as if the perforation would continue to get worse.
The researchers concluded that leaving these filters in the body for longer than a limited amount of time was likely to result in perforation more often than not. “We advocate filter retrieval as early as clinically indicated,” they wrote.
This study is used as evidence in many new Cook IVC filter lawsuits, in which plaintiffs claim that the manufacturer, Cook Medical, failed to warn about the serious risks of their devices, and failed to conduct appropriate safety trials prior to market release.
What is a Cook IVC Filter?
IVC filters are tiny cage-like or spider-like devices that are implanted into the inferior vena cava to catch blood clots before they can travel to the lungs, where they could cause pulmonary embolisms. The inferior vena cava is one of the two large veins that carry deoxygenated blood from the body back into the heart. In this case, the blood comes from the lower part of the body.
Patients with deep vein thrombosis—a condition in which blood clots can form in the deep veins of the legs, and later travel back to the lungs through the inferior vena cava—are typically prescribed blood-thinning drugs to keep the blood from clotting. Some patients are unable to take these drugs, however, because of other health risks.
These patients may be implanted with an IVC filter to temporarily prevent a pulmonary embolism. The key word is “temporary,” however, as the Cook Gunther Tulip and Celect IVC Filters were made to be retrievable, or removable. Unfortunately, they are often not removed in time, before they can start causing serious side effects.
The Cook Gunther Tulip, which was approved by the FDA in 2003, and the Cook Celect, approved in 2008, have been the two main Cook filters at issue in courts over the past few years.
FDA Warns About Safety Risks with IVC Filters
In 2010, the FDA released a safety communication warning physicians and patients about the risks associated with IVC filters. In it, they stated that they had received 921 adverse event reports involving these devices between 2005 and 2010. Of these:
• 328 involved device migration to another part of the body
• 146 involved embolizations (detachment of device components)
• 70 involved perforation of the IVC
• 56 involved filter fracture
The FDA noted that patients could be having these problems because the devices were remaining in the body for long periods of time—long after the risk for pulmonary embolism (PE) had subsided, and beyond the safe use of the device.
The FDA added that known long-term risks associated with IVC filters “include but are not limited to lower limb deep vein thrombosis (DVT), filter fracture, filter migration, filter embolization and IVC perforation.” They advised doctors to remove the filters as soon as possible after risk of PE had passed.
In May 2014, the FDA released an updated communication stating that they had examined all publicly available data from the medical literature to “assess whether there is a time during which the risk of having an IVC filter in place is expected to outweigh the benefits.” The mathematical model they developed suggested that IVC filters should be removed between 29 and 54 days after implantation.
They also stated that they were requiring IVC manufacturers, like Cook Medical, to collect additional clinical data to address remaining unanswered safety questions about these devices.
Research Reveals Serious Problems with Cook IVC Filters
Over the past several years, a number of studies have linked IVC filters with serious side effects. In addition to the 2012 study mentioned at the beginning of this article, there are several more, including one released in June 2015. For that study, researchers compared the Cook Celect filter with the Rex Medical Option filter. Researchers compared the two filters for 33 months at a single institution.
During that time, 99 Celect and 86 Option filters were implanted in patients. Researchers found no significant differences in retrieval rates, but they did find that the Celect filter had a significantly higher rate of strut perforation—which means that a piece of the device perforated the vein it was implanted in. In fact, the Celect had a 43 percent rate of perforation, compared to zero percent for the Option.
An earlier 2009 study found similar results. Researchers reviewed data from 115 patients who were implanted with a Cook Celect IVC filter between December 2005 and October 2007. That study also showed good retrieval rates, but indicated that doctors sometimes had difficulty getting the device out because it had become embedded in the vena cava wall.
In another 2012 study on in-hospital fatality rates, researchers found that IVC filters, on the whole, did not reduce mortality rates for stable patients. A 2013 editorial in JAMA Internal Medicine questioned the safety of IVC filters, stating the blood-clot reducing benefits of these devices had never been validated by empirical studies. Another study published that same year stated that a lack of standards as far as when to implant these filters varied widely among hospitals, raising questions about when these devices should be used.
Additionally, a recent 2015 study compared patients with pulmonary embolism who were treated with both blood-thinning drugs and an IVC, with those who received only blood-thinning drugs. Researchers found that the filters did not offer any additional protection against recurrent pulmonary embolism at three months. “These findings do not support the use of this type of filter in patients who can be treated with anticoagulation,” the researchers wrote.
Types of Possible Cook IVC Filter Injuries
Adverse event reports and scientific data reveal the following potential injuries associated with Cook IVC filters:
• Migration of the device to another part of the body
• Device perforates the inferior vena cava or other body organ, like the heart or lungs
• Components of the device become detached and travel elsewhere to cause injuries
• Device becomes embedded into the inferior vena cava
• Blood clots either where the filter is located or elsewhere
• Hemorrhage or infection
• Difficult or impossible removal
• Filter fracture causing chest pain and shortness of breath
Cook IVC Filter Lawsuits
After the 2012 study reported problems with the Cook IVC filter, awareness increased about the issues with these devices. Patients who had suffered serious injuries began to file Cook IVC filter lawsuits in an attempt to recover damages.
The Cook Gunther Tulip and Celect filters have been implanted in thousands of patients without adequate warnings concerning the risks mentioned above. In October 2015, the United States Judicial Panel on Multidistrict Litigation (JPML) consolidated all federal Cook IVC filter lawsuits in a multidistrict litigation (MDL) and transferred the cases to one court in the U.S. District Court for the Southern District of Indiana. At the time, the court transferred 27 cases into Indiana, but that number has now increased to over 100.
Indiana was the most convenient choice for the MDL because Cook is headquartered in Bloomington, and because half of the lawsuits were already pending there when the JPML made their decision. The consolidated litigation is expected to help improve efficiency in pre-trial proceedings, reduce risk of inconsistent rulings, and reduce risk of duplicative discovery.
In the transfer order, the court noted that all Cook IVC filter lawsuits involved common questions of fact, mainly that the filters were defectively designed, and likely to fracture, migrate, tilt, or perforate the inferior vena cava, causing injury.
Cook argued against consolidation, stating that the cases were too different, and that they involved different Cook IVC filters. They added that centralization would “encourage meritless claims against Cook.”
The Honorable Court Judge Richard L. Young is presiding over the proceedings.
A Cook IVC Filter Lawyer Can Help
If you or a loved one was implanted with a Cook IVC filter and then experienced a serious injury, you may be able to recover damages in a Cook IVC filter lawsuit. A medical device company is responsible for making sure their devices are safe and effective before releasing them on the market, and the facts of your case may prove that they failed to do that and should be held liable for your medical expenses.
At Chaffin Luhana, our IVC filter lawyers can help guide you in your legal options, and help you determine what you may be able to do if you have experienced serious Cook IVC filter problems. Call today for a free and confidential case evaluation at 1-888-316-2311.