New research suggests that automatic email alerts could help reduce complications associated with retrievable IVC filters.
The emails would be directed at physicians who implant the devices, and would remind doctors when it’s time to consider removing a patient’s IVC filter.
This is already being done at Boston’s Massachusetts General Hospital, where a computerized system uses billing codes to identify IVC filter placements performed at the facility. An interactive email is sent to each patient’s physician 30 days after implantation asking if the device has been retrieved.
No further emails are sent if a doctor responds in the affirmative. When the answer is no, the doctor is asked to provide information about whether there has been an unsuccessful retrieval attempt or give a reason for why the filter will not be retrieved.
Weekly follow-up emails are automatically sent to doctors who fail to respond to the initial communication.
To evaluate its effectiveness of the Mass General alert system, researchers writing in the American Journal of Cardiology evaluated 715 filter insertions before implementation and 355 after. They found that retrieval rates were higher among the group that had received email reminders (49.8% vs 31.2%) and remained higher even after excluding patients who died within 90 days or developed a permanent indication for a filter.
The median time to retrieval was also shorter in the email group (112 vs 146 day).
Most importantly, IVC filters were less likely to experience adverse events when their doctor received an email reminder. For example, just 9.4% of those in the email group experienced indwelling IVC complications, compared to 16.1% of non-email patients. The email group also saw lower rates of IVC filter thrombosis, deep vein thrombosis, pulmonary embolism, and death.
“We would hypothesize that the most likely mechanism for the association with reduction in indwelling complications seen in our study is the reduction in dwell times as a result of earlier retrieval,” the authors say. “Other studies have also found that complications occur more frequently as dwell time increases.”
IVC filters are indicated to treat patients at risk for pulmonary embolism when standard blood-thinning medications are not an option. The devices are inserted into the inferior vena cava to intercept blood clots before they can travel to the heart or lungs.
Retrievable IVC filters are intended to be removed once a patient is out of danger. But previous studies have suggested that the filters often remain in place far longer.
In 2010, 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. Among other things, the agency expressed concerns that retrievable IVC filters weren’t being removed in a timely manner.
In May 2014, the FDA issued a second alert to remind doctors of the importance of IVC filter retrieval.
Currently, more than 9,200 plaintiffs are pursuing IVC filter lawsuits over injuries and complications they claim resulted from defective, retrievable devices marketed by C.R. Bard, Inc. or Cook Medical, Inc. Among other things, they accuse defendants of failing to adequately inform doctors about the importance of IVC filter retrieval.
Federally-filed claims involving Bard’s products have been consolidated in the U.S. District Court, District of Arizona. The litigation’s first bellwether trial concluded in March, after a jury awarded $3.6 million to a recipient of Bard’s G2 IVC filter. However, Bard won the litigation’s second and third trials.
Federal lawsuits involving Cook Medical’s retrievable IVC filters are centralized in the U.S. District Court, Southern District of Indiana. The company won the litigation’s first bellwether trial in November 2017, while the second bellwether case was dismissed 4 months later.
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.