Inferior Vena Cava filters (IVC) is a small metal device that were designed to stop blood clots before they can travel to the lungs. The filter device looks like a metal cage and is surgically implanted into the patients vein. IVC filters are used in patients who cannot us blood thinners, which prevents the formation of blood clots.
HOW DO IVC FILTERS WORK?
The largest vein in the body is the inferior vena cava, moving deoxygenated blood from the lower legs to the heart and then to the lungs. The IVC filter is implanted in this vein to stop clots traveling through the vein into the lungs.
The device is implanted into the inferior vena cava using a catheter (thin tube). This is done through a small incision that is made in the neck or groin. The metal wires on the device capture and trap the blood clots before they have a chance to reach the lungs.
TYPES OF IVC FILTERS
There are two types of IVC filters, permanent and optional or retrievable.
Retrievable filters are used for and provide short-term protection. These filters are designed to be removed from the vein when the patient is no longer at risk for pulmonary embolism. However, retrievable filters can cause complications such as perforation of the blood vessel or organ and/or migration of the filter.
Permanent filters are used in patients who had recurrent deep vein thrombosis (DVT) while on blood thinning (anticoagulant) medications. Permanent IVC filters are also used in patients who cannot tolerate anti-coagulation medications because of an adverse reaction to them, bleeding, trauma or recent surgery.
COMMON USES OF THE IVC FILTERS
IVC filters are placed in patients who:
• Have been diagnosed with deep vein thrombosis
• Are immobile
• Are trauma victims
• Have been diagnosed with a pulmonary embolus
• Have recently had surgery
RETRIEVABLE IVC FILTER COMPLICATIONS
There are potential risks associated with retrievable IVC filters, like failing to stop blood clots from bypassing the device and damaging the vein. A more serious complication can occur if the device breaks apart and travels to another part of the body.
The U.S. Food and Drug Administration (FDA) announced a safety alert in 2010 in regards to the retrievable IVC filters. Nine hundred and twenty one reports had been received by the FDA of adverse effects spanning a five year period, 2005 to 2010. The events that were involved in the reports were:
• Filter perforation – in 70 patients
• Filter fracture – in 56 patients
• Device migration – in 328 patients
• Detaching of device components (device embolization) – in 146 patients
The majority of the adverse events, 35 percent, have involved the migration of the device. Migration is when the filter moves from its intended location. Embolization is listed by the FDA as the second most reported complication of the IVC filter.
Retrievable IVC filters were only intended to be used as short-term placement, but the FDA is reporting concern around the devices being left in patients long after the risks of pulmonary embolism has subsided. The updated safety communication by the FDA in 2014, has recommended the retrievable IVC filter device should be removed between the 29th and 54th day after implantation in which pulmonary embolism has subsided.
An IVC filter study confirmed the safety warnings by the FDA. Research studies confirmed the problems with retrievable IVC filters. The Journal of the Americal Medical Association (JAMA) released a study in 2013 that focused on the failure rate of the IVC filter. Researchers discovered that out of the 679 retrievable IVC filters inserted only 58 of them were removed.
When IVC filters are left in patients longer than is medically necessary the outcome was:
• Twenty five (25) patients suffered pulmonary embolisms
• 7.8% of patients have venous thrombotic events and
• 18.3% of attempts to remove the IVC filters failed
Doctors had made 13 unsuccessful removal attempts, 11 of those were in patients who had the filter for more than 85 days. Of the 13 unsuccessful attempts at removal:
• Removal could not be completed in 8 patients because the device was embedded
• Removal could not be completed in 3 patients because the filter protruded through the blood vessel
• Removal could not be completed in 2 patients because the device had migrated to an abnormal position
• Removal could not be completed in 1 patient because of a blood clot located inside the filter
IVC FILTERS THAT ARE PRONE TO FAILURE
• Bard’s G2
• Bard’s G2 express
• Bard’s Recovery
• Cook’s Celect
• Cook’s Gunther Tulip
IVC FILTER AND BLOOD CLOTS
Deep vein thrombosis (DVT) is when blood clots develop deep inside the pelvis, and upper and lower extremities. Deep vein thrombosis can cause death if the blood clots travel to the lungs, cutting off normal blood and oxygen flow to a person’s lungs. When the blood clot causes a blockage in the lung it is called a pulmonary embolism or PE. Pulmonary embolisms cause about 300,000 deaths every year, which is the third most common cause of death in hospital patients.
If you have developed complications as a result of the implantation of an IVC filter you may have legal options.