Radiologists uncover widespread variation in IVC filter removal rates, with deadly consequences
Radiologists have uncovered widespread variation in the removal of inferior vena cava (IVC) filters, with deadly consequences.
Such devices are typically implanted by rads or surgeons to prevent blood clots from traveling into the lungs. Experts recommend that physicians remove them, once the pulmonary embolism has subsided, typically within 90 days. Prolonged implementation can result in major complications including filter fracture, migration and even death, researchers detailed Aug. 13 in JACR.
Radiologists recently examined variation in IVC filter retrieval rates, utilizing Medicare claims submitted between 2016 and 2020. They found pervasive variation, with an average national retrieval rate of roughly 20%.
“Wide variation in device retrieval was observed amongst all hospital types: teaching and nonteaching, urban and rural, large and small bed size,” lead author Premal Trivedi, MD, MS, with the Department of Radiology at the University of Colorado Anschutz Medical Campus, Aurora, and colleagues advised. “Significant improvement in IVC filter retrieval is feasible in real world care settings if strategies from high performing facilities can be adapted to lower performing locations,” they added later.
The study included nearly 120,000 Medicare beneficiaries with IVC filters implanted across almost 2,500 facilities. Retrieval rates were universally low, with a median of 6% within three months and 15% after one year. Excluding patients who died within three months (about 30%), retrieval rates ranged from 0% to 100% across facilities. Among high-volume hospitals—in the top 25th percentile, implanting greater than 13 filters per year—one-year adjusted retrieval ranged from 0% to nearly 75% with an average of 20%.
Patient factors associated with failure to remove a filter included being over the age of 80, black race and Hispanic ethnicity. Meanwhile, nonteaching, small bed size and safety-net hospitals were all strongly associated with IVC filter nonretrieval, the authors reported. Across the study sample, radiologists implanted about 37% or over 44,000 IVC filters, highest among any specialty. Others on the list included surgeons at 31%, internal medicine specialists (21%), and other specialties (10%).
Trivedi and colleagues highlighted possible practice implications from the study:
- Patient selection: A focus on improving patient selection for IVC filter implantation is warranted. High mortality within three months (at 30.2%) likely reflects “severity of underlying medical disease rather than device-related risk.” Implantation is of “little value in patients with limited life expectancy,” the authors emphasized.
- Timely improvements: With only 6% of IVC filters retrieved within 90 days, improvements in timely removal are needed, experts contend. Previous research from the FDA has favored removal within between 29 and 54 days.
- New methods: IVC removal likely still should be attempted in cases of prolonged implantation. When standard techniques fail, physicians should consider other approaches such as laser and forceps. Previous studies have shown these methods can achieve successful removal in upward of 96% of patients with a low 3% major complication rate.
- Payment interventions: Quality programs such as the Medicare Merit-based Incentive Payment System (MIPS) could potentially move the needle on this issue. MIPS measure 421 currently tracks the percentage of patients who receive a retrievable IVC filter and receive an appropriate assessment after three months. Results from this new analysis could help to guide improvement efforts, with mortality after 90 days a possible second metric to track.
Read more, including potential study limitations, in the Journal of the American College of Radiology.
Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic.