Despite recommendations, ‘gap’ remains in inferior vena cava filter removal
Key takeaways:
- Inferior vena cava filters are recommended for temporary use to prevent pulmonary embolism when anticoagulation is contraindicated.
- In 2010, the FDA advised clinicians to remove the devices once the risk for PE subsided.
Although the insertion of inferior vena cava filters declined between 2013 and 2021, the rate of retrievals remained low, according to a study published in JAMA.
In the retrospective observational cohort study, researchers evaluated Medicare fee-for-service data on 270,866 patients (mean age, 75.1 years; 52.8% women) implanted with inferior vena cava (IVC) filters from 2013 through 2021.
Investigators assessed patterns in placement and retrieval of the filters, which are recommended for temporary use to prevent pulmonary embolism. In 2010, the FDA issued guidance calling for prompt removal of IVC filters once their clinical utility has diminished.
Results showed IVC filter insertions decreased from 44,680 in 2013 to 19,501 in 2021.
However, cumulative incidence of IVC filter retrieval was only 15.3% at median follow-up of 1.2 years and 16.8% at a maximum follow-up of 9 years.
IVC filter retrieval appeared lower among patients who were older, those who were Black and those who had more comorbidities. Filter retrieval occurred more frequently among patients treated at a large teaching hospital.
Among patients who did not have filters retrieved, researchers reported 2.2% (95% CI, 2.1-2.3) developed caval thrombosis and 9.2% (95% CI, 9-9.3) developed deep vein thrombosis.
“These findings confirm a gap in the FDA’s recommendations to retrieve the filters when clinically feasible,” lead author Enrico G. Ferro, MD, cardiology and electrophysiology fellow at Beth Israel Lahey Health, told Healio. “These data show we’re not there yet.”
Healio spoke with Ferro about the rationale for the study, the implications of the findings and the need for increased awareness about timely IVC filter retrieval.
Healio: When and why are IVC filters used?
Ferro: IVC filters are umbrella-like metal structures designed to prevent clots from the deep veins of the legs from going to the lungs. They generally are recommended for temporary use when a patient has an active risk for clot but cannot be anticoagulated. Some patients have reversible risk factors that put them at risk for having clots; however some risk factors are irreversible. For example, if you have a pro-thrombotic malignancy that may not be treated, then this risk factor would not change. In general, however, the guidelines are to use IVC filters temporarily.
Healio: What is the rationale for timely removal of IVC filters, and what is the recommended timeline for doing so?
Ferro: It’s recommended that they be removed because they are a foreign body, they’re made of metal and, paradoxically, they can create the problem they are meant to fix. Clots can form on them. Also, they can dislodge and move — or embolize — away from their original placement. As far as when they should be removed, this depends on how the risk for bleeding and the contraindication to anticoagulation are changing dynamically in the patient’s clinical course. This is why the FDA guidance says that we should try to remove them as soon as clinically feasible.
Healio: How did you conduct this study and what did you find?
Ferro: This study leveraged patients with Medicare fee-for-service insurance, which is a special population of interest that is very relevant to these devices. We studied this population from 2016 to 2023. We used insurance claims to understand what was happening in terms of volume of implants and retrievals, and to evaluate periprocedural complications.
We found that the volume of implants has decreased, from about 45,000 filters at the start of the study to about 20,000 by the end. The absolute number of retrievals was about the same, at 4,000 retrievals per year. If you decrease the number of implants, then the percentage of filters retrieved is artificially increasing, but the absolute number remains at about 4,000 per year. Approximately 94% of retrieval attempts were successful, and the complication rates around retrieval were low at about 3% to 4%.
Healio: What are the potential implications of your findings?
Ferro: The largest analysis before our study was the PRESERVE study, which was done in collaboration with the FDA and enrolled about 1,500 patients. These were from about 50 sites in the U.S. that were actively participating in the study. It was a subselection of the United States population, and the retrieval rate in this study was 45%. When we expand that to more than 270,000 patients getting filters in more than 3,800 hospitals across the country, we make it much more generalizable. More importantly, these were not hospitals that were actively enrolled in a study on this topic. The retrieval rate in the real world is 15%. I think that shows that when you look at real-world practices, it’s not quite the same.
Healio: What do you think should be done to encourage timely retrieval of IVC filters?
Ferro: It’s important to raise awareness about the recommendations for IVC filter retrieval and make plans at the time of implant on how to proceed afterward. For example, providers could implement a checklist that proactively considers the disposition of the filter. Importantly, this might not necessarily mean filter retrieval. There may be a subgroup of patients for whom the plan doesn’t include retrieval. For others, we might plan for retrieval or for re-evaluation in 3 months. There’s also the possibility for opportunistic techniques; namely, AI models could be used to identify an IVC filter that happens to be there during a CT scan, which would prompt a radiologist to inform the patient’s primary care physician about the presence of a filter. We also could use computerized reminders in electronic medical records, just to remind providers to re-evaluate the disposition plan. There are many ways in which this could be improved.
Reference:
For more information:
Enrico G. Ferro, MD, can be reached on X (formerly Twitter) at @enricoferromd.
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