Inferior vena cava (IVC) filters are devices that are placed within the inferior vena cava to stop a blood clot from reaching the lungs, resulting in a potentially fatal condition known as pulmonary embolism. Patients at risk for pulmonary embolism include those with venous thromboembolism and deep vein thrombosis. Typical treatment involves anticoagulants (bloodthinners), but sometimes IVC filters are used when these drugs are contraindicated. Recently, there have been concerns over the potential complications associated with IVC filters. The journal Seminars in Interventional Radiology published two new studies concerning IVC filters.
One study analyzed complications based on filter type. The goal was to help determine which patients would benefit from filter retrieval versus follow-up. Researchers performed a search of several databases to identify IVC filter types and device-specific complications from 1980 to 2014. The authors identified 23 IVC filter types, 14 of which were retrievable and 9 permanent. The study found that filters categorized as purely conical were associated with the highest risk of penetration (90-100%). The risk of IVC thrombosis was highest with cylindrical or umbrella elements (30-50%) and Conical Bard filters were associated with the highest reported risks of fracture (40%). “This information can be used to guide and optimize clinical management in patients with indwelling IVC filters.” the authors stated.
Another report published in the journal focused on medical device litigation involving IVC filters, noting a rising number cases in recent years. This led to two multidistrict litigations (MDLs), one for Cook’s filters and another for Bard’s. The authors state that both MDLs share common questions of facts, specifically whether the filter design and manufacturing practices made them unreasonably prone to complications. “The resolution of these cases will add to a larger legal debate concerning how much legal protection the 1976 Medical Device Amendments should offer firms from tort liability. As a specialty that often relies on medical devices, it is not only important for interventional radiologists to have a general understanding of medical device litigation but also to reflect upon the approaches to informed consent regarding these devices.” the authors state.