At the 2016 Society for Interventional Radiology (SIR) Annual Scientific Meeting, Michael Temple, MD, a pediatric interventional radiologist at the Hospital for Sick Children in Toronto, Ontario, presented preliminary results from a multi-institutional study of inferior vena cava (IVC) filter use in children. The study’s goal was to determine success rates, complications, and outcomes as well as usage patterns for IVC filters in children. Dr. Temple shared details of some of these preliminary results with Vascular Disease Management at the SIR meeting. 

VDM: Could you describe the impetus for the study?

Temple: The study came about as a result of a series of emails that were sent on the Society for Pediatric Interventional Radiology Listserv a number of years ago. People were asking questions about IVC filter insertion in children and about the potential issues related to their use. The group decided to pool their data to look at outcomes. 

VDM: What was the question that needed to be answered?

Temple: I think that this is very timely. In 2010, the FDA reported a series of complications that were associated with IVC filter insertions in adults, and they suggested that the filters be removed. Just last year, Drs. Gillespie and Johnson launched the PRESERVE study (clinicaltrials.gov/ct2/show/NCT02381509), a very large-scale pivotal study, to prospectively gather information on IVC filter insertion in adults. 

We’re looking to answer the same questions in children. What we’re really hoping to do is review the safety and efficacy of IVC filter use in children and to come up with success and complication rates across patient populations and across institutions. 

VDM: Can you go into detail about the design of the study?

Temple: This is a multisite, retrospective review study. The data are being collected using an online database. The study was launched in October 2014 and is open to all sites and specialties that perform IVC filter insertion in children. The original data elements were gleaned by a senior author group that inlcluded myself, Kamlesh Kukreja, MD, from Texas Children’s Hospital, and Joao Amaral, MD, from The Hospital for Sick Children in Toronto. 

We used the SIR reporting standards to create an initial data element collection form with changes made for the pediatric retrospective nature of the study. The Society for Pediatric Interventional Radiology board of directors and research committee reviewed the data. The data forms were then compiled into a database and a test group of institutions around the world entered fake patient data to help fine tune the data collection and the database itself. 

VDM: What, in your opinion, were the most important findings?

Temple: I have to preface these comments by saying that this is a preliminary study. We are still in the process of data collection, so this is a snapshot of the database as it exists right now. To summarize what we found, we are actually very technically successful in placing IVC filters. Of the 120 patients we’ve entered into the database so far, there was 1 patient in whom the insertion failed, so this translates to a 99.1% technical success insertion rate. In 2 patients the filters did not work in the way they were supposed to, so that translates to a very high effectiveness rate. Interestingly, there’s a very high mortality rate so far: 7 patients have died, which translates to about 6% of patients. None of the deaths were secondary to the filter insertion, removal, or the filters being in place themselves. The patients simply succumbed to their underlying disease. This reflects the acuity and the level of sickness of some of these patients in whom we are placing these filters. 

VDM: How could this change the way that these patients are treated?

Temple: I’m not sure that this study will necessarily change the way that we’re doing the procedure at this point. I’m hoping that the information will help guide us to make better choices. If we have a better handle on the risks and benefits of IVC filter insertion in children, it will allow us to better inform clinicians and patients and parents of the risks and benefits of using IVC filters.

VDM: What’s the most important take-away for interventionalists?

Temple: One of the basic take-aways for those who don’t work with pediatric interventions is that we can place IVC filters in children. We are very successful in doing it and we have a very high success rate. Like all other procedures, IVC filter insertions come with risks and complications and it’s very important to have very strong indications for filter placement, to share that information, and to have good communication with patients and their families. In my opinion, you should whenever possible, and as soon as possible, get the filters out. 

VDM: Anything else that you would like to share about the therapy or the information?

Temple: These are preliminary results, so they will certainly change as more data are entered, but that will make the study more complete and more robust. I hope that this will help lay the foundation for future pediatric interventional collaborative studies. The diseases that we see in our patients are very rare. Also, many procedures that we perform in children are more commonly performed in adults, so it’s harder for us to get the data that we need to help support our studies. I’m hoping that this will lay the groundwork for future collaborations for pediatric interventional radiologists to allow us to do more complex and prospective studies to help us better care for our patients. 

Editor’s note: Dr. Temple reports no disclosures related to the content herein.