An IVC filter replacement is a medical procedure that removes a patient’s IVC filter and inserts another one in its place. IVC filter replacement procedures are often done when there is a problem or medical complication with the implanted device, or if the implanted filter has been clogged with a blood clot. The procedure can be risky, though, and is often where surgeons first discover that the IVC filter has broken, a situation that often leads to an IVC filter lawsuit.
- 1. How do IVC filters work?
- 2. IVC filter replacements
- 3. Risks of IVC filter replacement procedures
- 4. Reasons for replacing an IVC filter
1. How do IVC filters work?
IVC filters work by keeping blood clots from moving from the legs into a patient’s heart or lungs, where they can cause potentially fatal pulmonary embolisms.
IVC filters, or inferior vena cava filters, are tiny medical devices that are implanted through an incision in a patient’s neck or groin. Once inside, they are navigated through the bloodstream to the inferior vena cava vein. This vein is the largest one in the body, and brings blood from the legs back to the heart and lungs.
IVC filters look like an umbrella frame, with several legs, or struts, protruding from the head of the device. During insertion and navigation, these struts are closed like an unused umbrella. Once positioned in the inferior vena cava vein, the struts in the IVC filter are sprung open to lodge in the wall of the vein.
Blood clots that form in a patient’s legs and travel through the bloodstream pose a serious threat: If they reach the lungs, they can block arteries in the lungs and create a pulmonary embolism. Around 100,000 Americans die every year from pulmonary embolisms.
When an IVC filter is in place in the inferior vena cava, though, these clots are supposed to get blocked by the filter, preventing a clot from reaching the heart or lungs where it could do lots of damage.
2. IVC filter replacements
Whether because the IVC filter has broken or because it has trapped a blood clot and gotten clogged, surgeons can replace an IVC filter during a replacement procedure.
All temporary IVC filters are equipped with a hook or a knob at one end, usually on the tip of the device’s head. Once pulled, the hook closes the IVC filter’s struts so it can be moved safely. After making an insertion in the patient’s neck or groin, a surgeon can work a catheter through the patient’s veins to the inferior vena cava. Once there, the surgeon can use the catheter to pull the filter’s hook, close the device, and take it out.
When the IVC filter has been removed, another one can be inserted in its place in the inferior vena cava.
3. Risks of IVC filter replacement procedures
IVC filter replacement procedures are risky if the filter has been in place for too long or has fractured.
Most IVC filters are meant to be temporary solutions. The FDA has recommended that they be removed as soon as the risks for a pulmonary embolism have passed.1 The FDA has also relied on a medical study that suggested that the risks presented by an IVC filter begin to outweigh its benefits between 29 and 54 days after being implanted.2
If left in longer than this time period, an IVC filter can become so lodged into the walls of the vein that it is difficult to remove without using so much force that it could damage the vein.
Worse, IVC filters can break or fracture after being implanted. If the device is fractured, but has held its position, it is likely to break into multiple parts during the IVC filter replacement procedure. If a part of the filter is not captured during the procedure, it can migrate through the bloodstream and cause damage.
4. Reasons for replacing an IVC filter
There are two main reasons for replacing an IVC filter that has already been implanted:
- The IVC filter has broken, or
- The IVC filter has caught a blood clot and gotten clogged.
Fractured or broken IVC filters need to be removed as soon as possible, as broken pieces of the device can dislodge and migrate. Because the blood flow in the inferior vena cava would carry any broken pieces of the IVC filter to the heart and lungs, removing and replacing a broken device is critical. Additionally, the broken filter is unlikely to prevent blood clots from passing through the inferior vena cava and causing a pulmonary embolism.
In other cases, the IVC filter needs to be replaced because it has stopped a blood clot. Taking the IVC filter out, removing the blood clot, and putting a new filter in the inferior vena cava vein can prevent another blood clot from traveling to the lungs.
References:
- U.S. Food and Drug Administration, “Removing Retrievable Inferior Vena Cava Filters: FDA Safety Communication” (May 6, 2014).
- Morales JP, et al., “Decision analysis of retrievable inferior vena cava filters in patients without pulmonary embolism,” Journal of Vascular Surgery 1(4):376-84 (October 2013).