ORLANDO – Roughly half of all inferior vena cava filter perforations voluntarily reported between 2000 and 2011 were asymptomatic and were noted as incidental findings on imaging studies, Dr. Emily A. Wood reported at the annual meeting of the American Venous Forum.
"An important thing to note about IVC perforation is that a large proportion of the patients are actually asymptomatic. Our study noted an average of 47% – almost half – of perforations were incidental findings on imaging," said Dr. Wood, a general surgery resident at Stony Brook (N.Y.) University.
IVC filter placement has more than doubled in the last decade – from 30,756 to 65,041 (J. Am. Coll. Radiol. 2011;8:483-9). While uncomplicated filter placement is a relatively straightforward ambulatory procedure, IVC filter registration and reporting of outcomes are not mandatory. Little is known about the number of adverse events related to these procedures. However, IVC perforation is an easily quantifiable event, said Dr. Wood.
The researchers used the Food and Drug Administration’s Manufacturer and User Facility Device Experience (MAUDE) database. They performed a retrospective review of 3,311 reported adverse events using filter/intravascular/cardiovascular product class search criteria from January 2000 to December 2011.
They excluded adverse event descriptions that did not specifically involve IVC perforation, including: device malfunction, failure to deploy device properly, migration/tilting, and cardiopulmonary system involvement. Outcomes of interest included clinical presentation, type of device utilized, and management (including retrievability rates).
The researchers found 391 (11%) instances of IVC perforation were reported over the 11-year period of interest. In particular, a fivefold increase in adverse events related to IVC perforation occurred from 2003 to 2004. The annual distribution of cases was 35 (12%); the annual accrual rate has not significantly increased. "Remember that this is not a universal registry and that it is voluntary. Thus, it is not entirely representative of the type of complications that actually occurred during those years," she said.
The most commonly involved structure was the aorta (43), followed by small bowel (36), vertebral body (14), and others. By far, the most commonly used filter type was the Bard G2 (168), followed by the Bard Recovery (59), the Cook Celect (46), and others.
"The majority of these filters are left in place, despite the adverse event. In other words, a perforation alone is not necessarily an indication for device removal," said Dr. Wood (see table).
IVC filter placement is not free from complications and therefore indications for filter placement should be carefully reviewed prior to any procedure. Retrievable filters are commonly involved in IVC perforation. "This gives more weight to the fact that these patients should be followed more closely and that a scheduled date for retrieval should be set, if indicated."
The authors reported that they have no relevant disclosures.