An IVC Filter, known as Inferior Vena Cava Filter or a type of filter known Greenfield Filter, is a small device that is implanted into the Inferior Vena Cava (a large blood vein in the abdomen) to prevent Pulmonary Embolism. In most cases, this comes from the embolism of blood clots in the deep veins in the legs, medically called Deep Vein Thrombosis. The IVC Filter practically catches blood clots, preventing them to reach the lungs.
When the IVC Filter is used (General Information)
Anticoagulants are a group of pharmaceuticals that stop blood from clotting and are used as a medication in thrombotic patients. However, such medications don’t always work or have a small significant impact, depending on the condition. Additionally, they may cause complications to patients, making them impossible to be used as a treatment.
In the cases where medical substances can’t be used – medically called contraindication, an IVC Filter or Greenfield Filter is the best solution to prevent pulmonary embolism.
IVC Filter Placement
Recent designs have made placement of the IVC Filter much easier in contrast with the surgical solutions available in the past. Depending on the location of the blood clots, the catheter (thin tube) is inserted via the large vein in the groin (femoral vein), arm veins or the large neck vein (internal jugular vein). The catheter is guided to the Inferior Vena Cava by a fluoroscope or ultrasound, after which the Greenfield Filter is inserted and attached to the IVC walls.
IVC Filter Removal
Removal depends on the kind of used filter and condition. If the filter is permanent on patients with a risk of recurring thrombosis, it stays in the IVC and is not taken out. While recent designs of IVC Filters are temporary and have small hooks that can be used to be taken out.
IVC Filter Complications
Although filter designs and techniques have made risks quite low, complications still exist. Hemorrhage, damaged blood vessels or filter misplacement are known to have occurred during filter placement. In the minority of cases, long-term complications may be present with recurrent thrombosis, filter migration or caval occlusion.
Please continue reading the other articles throughout the site for more specific information on placement, removal, types, brands and complications of IVC Filters and Greenfield Filters.
Bard Recovery IVC Filter System Problems
Introduced in April of 2003, the Bard Recovery IVC filter system was quickly replaced because of the unexpectedly high number of incident reports filed with the FDA regarding device failure, fracture, and migration. In a number or medical studies, the failure rate for the Bard Recovery IVC filter system was determined to be between 21% and 31.7%.
The New England Society for Vascular Surgery conducted a study of adverse event reports filed with the FDA regarding the Bard Recovery IVC filter in 2005, and concluded that the failure rate of the device was roughly 31.7%.
In a 2008 study by the Journal of Vascular and Interventional Radiology, a 21% Bard Recovery IVC failure rate was reported.
In 2010, the Archives of Internal Medicine found a 25% failure rate for the Bard Recovery IVC filter. Researchers also found that in more than 70% of patients, fractured parts of the Bard Recovery IVC filter migrated to the heart.
Bard G2 IVC Filter System Problems
The Bard G2 IVC filter system was introduced as a replacement for the Bard Recovery IVC in 2005, and was marketed as having “improved centering”, “increased migration resistance”, and “enhanced fracture resistance”. Unfortunately, the device has also been linked to an unacceptably high rate of fracture, failure, and migration.
The Archives of Internal Medicine published a Bard G2 IVC filter study in August 2010, reporting that the complication rate for this potentially defective medical device is as high as 12%. 6 out of 52 study participants suffered as a result of Bard G2 IVC filter fracture.
One patient experienced blocked blood flow to the liver, another experienced blocked blood flow to the lungs, and in the remaining 4 patients fragments of the Bard G2 IVC filter remained near the device.
The Bard G2 IVC filter is meant to be a temporary measure to prevent pulmonary embolism, and researchers in the above-mentioned study also found that the rate of failure or complication increases the longer the device is left in place.
Though this study showed a lower rate of failure for the Bard G2 IVC filter system than for the Bard Recovery filter, it is important to note that in the study the Bard Recovery IVC filter was in place for an average of 50 months, while the G2 system was only in place for an average of 24 months.
This lead scientists to conclude that the number of Bard G2 IVC system failures will most likely increase in the next few years.
Bard IVC Filter Injuries
The purpose of a Bard IVC filter is to intercept and stop blood clots as they travel through the inferior vena cava (IVC). This is done to prevent a pulmonary embolism in patients who are unable to take anticoagulant medications or who are immobilized for some reason.
Both the Bard Recovery IVC filter system and the Bard G2 IVC filter system have displayed an unacceptably high rate of failure, leading to serious injuries such as:
- Breathing problems
- Cardiac tamponade
- Chest pain
- Heart perforation
- Hemorrhagic pericardial effusion
- Lung perforation
- Pericardial pamponade
- Vena cava puncture
Furthermore, while both of these devices are marketed as being removable, in some cases the Bard IVC filter was not able to be removed through surgery.
Problems with Bard IVC Recovery and G2 Filters
In April 2003, Bard introduced the Recovery IVC filter. As a result of several reports of broken filters, Bard redesigned the device and released the Bard G2 IVC filter in October 2005.
This model was meant to be more resistant to fractures than its predecessor, but has now been the subject of numerous reports of IVC filter fracture and migration.
In a study conducted by the Archives of Internal Medicine, 80 patients who received either one of the Bard IVC filters at a New York hospital between 2004 and 2009 were monitored.
Of these patients, at least 13 experienced IVC fracture, with 7 of these cases pertaining to the earlier model, the Bard Recovery IVC filter. Of these 7 patients, 5 experienced fractured IVC filters that traveled to the heart, causing rapid heartbeat, fluid buildup, and one death.
In the 52 patients studied who had been implanted with the Bard G2 IVC filter, 6 experienced IVC filter fractures, some of which traveled to the liver and the lungs.
According to the study, about 16% of the filters fractured. Of these fractured filters, roughly 71% of the patients had a piece of a fractured filter that traveled to the heart. Others experienced filter piece migration to the liver and within the veins.
FDA Warning about Bard IVC Filters
The FDA has issued a warning regarding the safety of IVC filters made by C.R. Bard, the company that makes the majority of IVC filters. There is a high rate of fracture associated with Bard IVC filters which can lead to perforation of the interior vena cava (IVC).
Device migration and detachment of the device are also serious and life-threatening risks associated with defective IVC filters. Fractured IVC filters can lead to a number of debilitating side effects, including fluid build-up, rapid heartbeat, and even sudden death.