IVC Filters: Are They Worth the Risk?
An IVC filter is a mechanical device inserted into a patient’s inferior vena cava (IVC), which is a major vein in the body delivering deoxygenated blood to the heart and lungs. Certain people are at risk of developing a blood clot in their legs known as a deep vein thrombosis (DVT), which can break loose and travel through the IVC, eventually lodging in the lungs where it can cause a pulmonary embolism, which is a serious and potentially fatal condition. IVC filters are implanted in the IVC to trap any dislodged blood clot before it can make its way into the lungs.
IVC filters sound like a lifesaver, and they can be. But several problems have been noted with the use of the filters, leading many doctors to question whether they are worth the risk to patient safety. A group of doctors at Boston Medical Center conducted a review of 952 patients with IVC filters inserted into their body. Below are some of the conclusions drawn from this study.
IVC Filters Dislodge and Break
The fact that IVC filters can break apart and cause serious organ damage is becoming well-known. In fact, patients have already initiated lawsuits in California and around the country seeking damages for the harm caused by IVC filters. The doctors in the Boston study found at least ten serious complications in the patients they reviewed. In nine individuals, the IVC filter had migrated to another part of the body. In two individuals, the IVC filter had fractured. The filters and their broken pieces may become embedded in the IVC, damage blood vessels or get lodged in the heart.
IVC Filters are Designed to be Retrievable, Yet They Rarely Are
Since 2003, IVC filters have been designed to be retrievable, so they can be removed from the body when they are no longer needed. Yet of the 952 patients studied, 273 were given permanent filters, and of the 679 retrievable filters, attempts were made to retrieve only 71 of them. Of those 71 attempts, only 58 were successful. Of the 13 retrieval failures, eight filters were embedded in the patients’ IVC, and another three had the filter protruding through a blood vessel. Two patients had an abnormal filter position that prohibited retrieval. Only one of these patients had an actual blood clot trapped in the filter.
Even when IVC filters are eventually removed, they are retrieved after a lengthy time in the body. A 2014 FDA communication recommends that IVC filters be removed by the 54th day after implantation. Yet in the Boston study, the filters were removed on average 122 days after insertion, and as long as 1,931 days.
IVC Filters are Used when They Don’t Need to Be
One would think that IVC filters would be used when a DVT is present or likely to develop, or when the use of anticoagulants to prevent or break up a blood clot is contraindicated in a particular patient. Yet the study of 952 implants found that 375 filters were inserted without any evidence of DVT. Additionally, only 31 of the patients who received an IVC filter had actually sustained a DVT and failed anticoagulant therapy. A full one-fourth of the patients who received an IVC filter also had anticoagulant therapy while they were in the hospital, which clearly shows that the use of anticoagulants was not contraindicated for these patients.
Blood Thinners are Safer and More Effective
It is apparent that often times doctors choose to insert an IVC filter as a preventive measure when the patient does not currently have a DVT. However, the study shows that retrieval rates for the filters are lower when they are inserted as a preventive measure (prophylaxis) than when a patient actually has a DVT. The use of IVC filters for prophylaxis remains controversial; an IVC does not prevent development of a DVT like blood thinners do, and it does not even entirely prevent pulmonary embolism (of the 952 patients studied, 41 actually developed a DVT as a consequence of the insertion of an IVC filter!). And one must not forget the serious complications when the device fractures and migrates to the heart or other vital organs, puncturing blood vessels and causing serious damage.
Even though almost all IVC filters are designed for retrieval, less than ten percent of the patients studied actually had their filters successfully retrieved. Meanwhile, there is no medical protocol in place for conducting routine imaging of the insertion site, either after filter placement or following retrieval.
The 2012 American College of Chest Physicians guidelines recommend that an IVC filter should not be placed in a patient who does not currently have a DVT. This recommendation is based on the lack of any solid evidence that IVC filters produce better results than anticoagulants.
If you have suffered injury due to a defective IVC filter, contact the defective medical device attorneys of Magaña, Cathcart & McCarthy at 310-553-6630.
