Inferior Vena Cava (IVC) filters may not be the best treatment option for patients who suffer from venous thromboembolism, or VTE, according to a new study which suggests a higher risk of 30-day mortality among those who receive the filters.
IVC filters are tiny, wire devices that are used to treat people at risk for pulmonary embolism – a possible consequence of VTE – who are unable for various reasons to use standard blood-thinning medications. Once inserted into the inferior vena cava, the cage-like implants will intercept and prevent blood clots that have broken loose from elsewhere in the body from travelling to the heart or lungs.
Many of the IVC filters currently in use are intended to be retrieved once a patient is no longer at risk for pulmonary embolism.
For this new study, researchers from Harvard Medical analyzed data on more than 126,000 patients who had been hospitalized with VTE, all of whom were included in State Inpatient Database or the State Emergency Database from hospitals in California (2005-2011), Florida (2005- 2013) and New York (2005-2012).
The data set included more than 45,700 individuals who had undergone IVC filter placement. The average age of the cohort was 66.9 years, while the mean time to IVC filter placement was 5 days. The study team was unable to determine whether the IVC filters used were retrievable or whether they were ever retrieved.
Two different statistical methods were used to analyze the data, both of which indicated that IVC filters were associated in an 18% increase in the 30-day mortality risk
The authors of the study called for randomized clinical trials to determine the efficacy of IVC filters, pointing out that the devices – which have been available since the 1960s — are implanted in more than 100,000 U.S. patients annually, despite the absence of quality data supporting their use.
This is not the only time questions have been raised in regards to IVC filters.
In 2010, for example, the U.S. Food & Drug Administration (FDA) warned that its adverse event database had logged more than 900 IVC filter complication reports, including incidents of migration, filter fracture, and embolization, as well as cases where pieces of an IVC filter perforated organs and blood vessels.
“The FDA is concerned that these retrievable IVC filters, intended for short-term placement, are not always removed once a patient’s risk for PE subsides,” the alert stated. “Known long term risks associated with IVC filters include but are not limited to lower limb deep vein thrombosis (DVT), filter fracture, filter migration, filter embolization and IVC perforation”
In May 2014, the agency issued a second alert to remind doctors of the importance of IVC filter retrieval.
Thousands of people across the United States are currently pursuing IVC filter lawsuits for injuries and complications they allegedly suffered due to the malfunction of retrievable devices marketed by C.R. Bard, Inc. and Cook Medical, Inc.
More than 4,500 claims involving Bard IVC filters have been centralized in a multidistrict litigation now underway in the U.S. District Court, District of Arizona. The litigation’s first bellwether trial concluded in March, after a jury found the company negligent for failing to warn doctors about the dangers potentially associated with the G2 IVC filter. The plaintiff was awarded $1.6 million in actual damages and $2 million in punitive damages.
C.R. Bard won the second bellwether trial in May. The IVC filter lawsuit selected for the proceeding’s third trial was dismissed earlier this month, after a judge found that the plaintiff had waited too long to file the case.
A second multidistrict litigation involving more than 4,300 Cook Medical IVC filter lawsuits is currently underway in the U.S. District Court, Southern District of Indiana.
The company prevailed in the litigation’s first bellwether trial, which concluded in November 2017. A judge dismissed the second bellwether four months later. A third federal bellwether is set for September 2018.
In May, a Texas state court jury awarded $1.2 million to firefighter who suffered serious complications after a Cook Celect filter tilted, migrated, and perforated his aorta and duodenum.