Most manufacturers make their inferior vena cava (IVC) filters of non-ferromagnetic materials, meaning IVC filters are typically MRI safe. Even in filters that include some weakly ferromagnetic materials, it only takes a few weeks for the tissue growth around the filter to secure it firmly to the vein wall. This ensures that it should not shift or cause other problems during magnetic resonance imaging (MRI).
This does not mean, however, that an IVC filter should stay in place for longer than recommended. The U.S. Food and Drug Administration recommends removing the filter as soon as practically possible and before leaving it in place for two months or more. The same tissue growth that makes an MRI safe with weakly ferromagnetic filters can make them difficult or impossible to remove later.
IVC Filters and MRIs
Surgeons place IVC filters in the inferior vena cava vein to snare any type of embolism before it reaches the heart and lungs. These devices are, in theory, temporary. IVC filters address an acute risk of this type of concern when other treatments such as blood thinners are not possible.
When placed, IVC filters hook into the vein wall. Over the next four to six weeks, the tissue around the filter heals and grows, securing the filter by incorporating it into the vein wall. The new growth of tissue makes it difficult to move and sometimes impossible to remove. This is a positive thing when you need an MRI because it is very unlikely that the filter will move as a result. However, this can also make retrieving the filter at a later date extremely complicated.
Talk to Your Doctor About Your IVC Filter Before an MRI
If you do have an IVC filter and need an MRI, be sure to tell your doctor about the implant. Most people with weakly ferromagnetic or non-MRI safe implants will receive a card for their wallet or another way to warn first responders, but it cannot hurt to double-check.
IVC Filters May Make Your MRI Difficult to Read
If the area that requires MR imaging is close to the IVC filter, there may be some issues with the quality of the imaging related to the proximity of the filter. Depending on how close the area is, your doctor may need to change the parameters used for capturing the MRI or make other adjustments to how they get a look inside your body.
If you have a newly-placed ferromagnetic implant, if the implant is in the exact area where your doctors need to see, or if your doctor is not comfortable with an MRI for other reasons, a computerized tomography (CT) scan with contrast is usually a viable alternative.
IVC Filters May Cause Complications Unrelated to MR Imaging
IVC filters are generally safe during MRIs, but the devices do have a history of complications as recorded in studies, by the U.S. Food and Drug Administration (FDA), and in anecdotal tales from thousands of patients. Complications associated with IVC filters generally include:
- Complications related to insertion
- Device failure, including fracture
- Device migration
- Device embolization
- Vein wall perforation
- Organ damage related to the devices
- Inability to remove the device
The FDA first issued a warning about these complications in 2010 and recommended removing them as soon as they were no longer useful for reducing an acute risk. Later, the FDA revised this removal recommendation for IVC filters for most patients before 54 days post-placement. Still, according to one of the 2019 International Symposium on Endovascular Therapy, too many filters are remaining in place too long, and many doctors never put a plan in place to remove them at all.
More Than 10,000 Plaintiffs Seek Compensation From Filter Manufacturers
As a result of complications from IVC filters they allege are unsafe, more than 10,000 plaintiffs filed suit in U.S. federal courts against manufacturers C.R. Bard, Cook Medical, and Boston Scientific. The courts consolidated many of these suits into MDL No. 2570 against Cook Medical in the Southern District of Indiana or MDL No. 2641 against C.R. Bard in the U.S. District Court District of Arizona.
If you or a loved one had an IVC filter placed and later suffered complications, the dangerous and defective medical device attorneys from Tosi & Rose will review your case at no cost to you. Call us today at 888-311-8292 for your complimentary consultation with a member of our team.