An inferior vena cava (“IVC”) filter is a small, cage-like device that is implanted in the IVC, which is the main vein that returns blood from the lower half of the body to the heart and lungs. The filter is designed to capture migrating blood clots that have broken loose from the arterial wall in an individual’s legs and that is moving toward the heart and lungs, allowing blood to continue to flow around the trapped blood clot.
IVC filters are placed in patients who are at risk for a pulmonary embolism, a blockage of one or both pulmonary arteries, which could result in difficulty breathing, chest pain, and/or death. The devices were first made available to the medical community in the 1960s, and are meant to be used in situations when anticoagulant therapy fails or cannot be used to treat pulmonary thromboembolism or during emergency treatment following a massive pulmonary embolism where the anticipated benefits of conventional therapy are reduced.
On August 9, 2010, the U.S. Food and Drug Administration (“FDA”) issued a safety warning regarding the risks associated with long-term use of IVC filters, which included lower limb deep vein thrombosis (DVT), filter fracture, filter migration, filter embolization (movement of the entire filter or fracture fragments to the heart or lungs) and IVC perforation. The FDA had received 921 adverse event reports on the devices since 2005.
In March 2013, the Journal of the American Medical Association’s published a study that examined the management and complications of IVC filters in 952 patients. Of the 952 patients, 680 received retrievable filters, but only 58 of 680 patients had their IVC filters successfully removed. The study further found that the IVC filter failed to protect eight percent of patients with the device from a pulmonary embolism.
On May 6, 2014, the FDA updated their 2010 safety communication by stating that IVC occlusion was a long-term risk of IVC filter implantation. Further, through quantitative decision analysis, the FDA determined that the ideal window for retrieval of the IVC filter is between 29 and 54 days after implantation in order to minimize complications. However, the organization stated that additional clinical data will be collected to address unanswered safety questions regarding both permanent and retrievable IVC filters.
In Spring 2015, the PRESERVE Study (Predicting the Safety and Effectiveness of Inferior Vena Cava Filters), which will directly address the FDA’s 2010 safety alert, enrolled its first patient. Around 2,100 total patients will be enrolled in the study, with at least 300 patients enrolled for each of the seven participating filter manufacturers. “The manufacturers and devices that will be included in the study are ALN Implants Chirurgicaux (ALN Vena Cava Filters); Argon Medical Devices, Inc. (Option Elite Retrievable Vena Cava Filter designed and manufactured by Rex Medical); B. Braun Interventional Systems Inc. (VenaTech LP Vena Cava Filter); Bard Peripheral Vascular, Inc. (Denali Vena Cava Filter System); Cook Incorporated (Cook Günther Tulip Vena Cava Filter); Cordis Corporation (Cordis OptEase Retrievable Vena Cava Filter/Cordis TrapEase Vena Cava Filter); and Volcano Corporation (Crux Vena Cava Filter System).” The study will last for five years, but it has been estimated that the FDA’s final decision as to how to appropriately respond to the results may not be known for at least a decade.
In October 2015, the Annals of Surgery published an article that concluded the IVC filters not only failed to effectively prevent pulmonary emboli from occurring in trauma patients, but also caused thrombi to occur. After examining the results of over 30,000 trauma patients who received filters to those who did not, researchers discovered that almost twice as many patients who had an IVC filter implanted died, five times as many developed DVTs, four times as many developed thromboemboli, and twice as many developed pulmonary embolus.
Plaintiffs in the litigations involving injuries caused by the device allege retrievable IVC filters are defective and have filed various lawsuits against the two primary manufacturers: (1) Cook Group, Inc.; Cook Medical Incorporated aka Cook Medical, Inc.; Cook Medical, LLC; Cook Incorporated; Medical Engineering and Development Institute, Inc.; Cook Medical Technologies; Cook Denmark International APS; Cook Denmark Holding APS; Cook Group Europe APS; Cook Nederland BV; and William Cook Europe APS (collectively, “Cook”); and (2) C.R. Bard, Inc. and Bard Peripheral Vascular, Inc. (together, “Bard”).