What is an IVC Filter?

IVC filters are small, cage-like devices placed in the inferior vena cava—the largest vein in the body. IVC filters stop blood clots from moving to the lungs, preventing pulmonary embolism. Due to several serious complications, healthcare providers often recommend IVC filter removal within 29 to 54 days after filter placement.

How Do IVC Filters Stop Blood Clots? 

IVC filters feature long wire legs that spread to the walls of the inferior vena cava. The bends of these structures ensure that the filter securely attaches to the vena cava while blood flow continues through the filter. This ensures that any blood clots that pass through are blocked.

When a blood clot is trapped by an IVC filter, it remains in the filter, breaking down over time until it either disappears or reduces to a size that poses minimal risk to the lungs.

What are IVC Filters? 

An interventional radiologist may recommend IVC filter placement in patients who experienced major procedures or traumatic incidents that resulted in blood loss. These devices are particularly helpful when blood thinning medication might not be appropriate or effective.

Initially, IVC filters were designed for patients at risk of deep vein thrombosis (DVT) or who couldn’t undergo anticoagulation therapy. But when retrievable IVC filters were first introduced in the early 90s, their application broadened to include patients with diverse medical conditions. By 2016, IVC filters were incorporated into numerous treatment plans, sometimes as a preventive measure for patients with spinal cord injuries and those who experienced multiple medical traumas. These filters are also usually paired with blood thinners. 

Named after the vein where the medical device is placed, IVC filters are positioned in the inferior vena cava, which courses through the middle and lower body. After it transports oxygen to the lower half of the body, the blood circulates back up the inferior vena cava to the heart to retrieve fresh oxygen from the lungs.

Common Conditions that Need IVC Filter Placement:

• Deep vein thrombosis
• Pulmonary embolism
• Limited physical mobility
• Experiencing significant trauma, major surgeries, or traumatic accidents that lead to blood loss can trigger the body’s clotting response, potentially causing deep vein thrombosis. DVT starts as a blood clot in the veins of the lower thighs and legs.

Signs of Deep Vein Thrombosis:

• Sensitivity or warmth over the affected vein
• Swelling or pain in the thigh or lower leg
• Red skin

If blood clots from DVT dislodge, they could make their way to the lungs, resulting in a life-threatening condition known as pulmonary embolism (PE). Pulmonary emboli can inflict lasting damage to the lungs or decrease oxygen in the blood, jeopardizing other parts of the body.

IVC Filter Placement and Retrieval

IVC filters are placed and retrieved by interventional radiologists. These health care professionals specialize in minimally invasive procedures, using imaging technology, such as ultrasounds, to navigate their procedures.

During the filter placement, the interventional radiologist creates a small opening in your neck or upper leg and inserts a catheter. They guide the catheter through the blood vessels using an imaging device to target the inferior vena cava.

Once the catheter is in place, the radiologist uses a specialized tool to insert a compressed IVC filter through the catheter. As the filter passes through the catheter into the inferior vena cava, it expands, securing its place within the blood vessel. The catheter is then carefully removed, and the incision is sealed.

IVC filter removal follows a similar process. An interventional radiologist uses a catheter and specialized tools to retract the filter, collapsing it for easy removal. However, if complications arise, such as the filter migrating, fracturing, or becoming entrenched in the vena cava wall prior to the scheduled retrieval, more advanced removal techniques may be required.

One method uses lasers to delicately remove the scar tissue surrounding the filter’s struts within the vena cava wall, ensuring a successful filter removal.

Types of IVC Filters

IVC filters are available in permanent and retrievable forms.

Permanent IVC filter models cater to patients with ongoing clotting disorders who can’t be put on blood thinning medication or other interventions.

Retrievable IVC filters, on the other hand, are meant for temporary use. They are removed once the blood clot threat has subsided. Retrievable IVC filters are typically recommended for patients with short-term blood clot risks. However, many of these retrievable filters have remained in place for extended periods of time.

If left in for too long, retrievable IVC filters could fracture or migrate, leading to severe complications. In some cases, filter failures have resulted in internal injuries and deaths.

The U.S. Food and Drug Administration (FDA) recommends that retrievable IVC filters are removed as soon as the threat of blood clots subsides.

How to Prepare for an IVC Filter Procedure

Before undergoing an IVC filter placement or removal, you’ll want to consult with your healthcare provider about the necessary preparations.

Create a list of the medications you take, and discuss them in detail with your physician before the procedure. There may be recommendations to adjust or discontinue specific medications that could interfere with the procedure’s success. Only stop taking medication if directed by your healthcare provider.

Do not consume any food after midnight the night before the IVC filter procedure. Limit your water intake to 12 ounces max between midnight and two hours before the procedure. Abstain from eating and drinking in the two hours leading up to the procedure.

Preparation Checklist for IVC Filter Placement or Removal:

• Avoid using make up, creams, or lotions. 
• Wear glasses—not contacts—on the procedure day.
• Safely store piercings and other jewelry at home.
• Only take medications specified by your doctor on the day of the procedure.
• Wear comfy, loose clothing.

What to Expect During an IVC Filter Procedure

The procedure typically lasts 30 minutes. However, it can extend to 90 minutes if advanced filter retrieval techniques become necessary.

Oftentimes, patients receive a local anesthetic at the incision site, but are usually kept awake during the IVC filter placement or removal. You will more than likely sense pressure near the incision during catheter insertion and its subsequent removal.

Most patients can get back to their regular routine within one day.

IVC Filter Recovery

After the procedure is complete, you will spend a few hours in recovery.

You’ll want to keep the bandage over the incision and ensure it remains dry for 24 hours following the procedure. This means you’ll need to avoid bathing and showering. 

You may experience soreness at the incision site for a couple days. You can use over-the-counter pain relief medication to manage this, if need be.

Avoid certain activities and movements—especially stretching—for the first few days after the procedure. Your healthcare provider will give you a list of actions to avoid.

You should reach out to your healthcare provider if you experience: 

• Bleeding at the incision site
• Chest pain
• Sensations of cold or numbness in limbs
• Persistent headaches or nausea
• Any discharge from the incision area
• A fever of 100.4 degrees or more
• Incision pain that doesn’t get better
• Increased swelling and redness at the incision site

IVC filters do not trigger metal detectors, and they are safe for MRI scans. However, it’s important to let the doctor and imaging technician know you have an IVC filter if you need to have any imaging performed.  

IVC Filter Complications

Complications can arise during IVC filter placement, after it has been in the inferior vena cava for a period of time, or during the filter removal process. 

The more serious complications can lead to lasting injuries or even death, and could make filter retrieval challenging, or even impossible.

Fortunately, most complications that arise from IVC filter placement are typically minor and manageable.

IVC Filter Placement Complications:

• Malposition: At times, IVC filters may not be positioned correctly. It’s possible for the filter to be positioned on the wrong side of the renal vein, compromising its blood clot-catching capacity. It could also be placed in the wrong blood vessel.
• Defective Filter Deployment: This happens when the IVC filter’s struts entangle or don’t expand/anchor within the vein correctly.
• Incision site issues: Minor complications like bleeding, unintended blood vessel punctures, and infections can occur. Less than 1% escalate into severe complications.

The most critical side effects of IVC filters are delayed complications, which can result in serious injuries and, occasionally, death.

Delayed IVC Filter Complications:

• Deep Vein Thrombosis: While IVC filters aim to stop blood clots from DVT from reaching the lungs, some studies indicate that these devices could elevate the DVT risk in patients post filter placement.
• Migration: IVC filters can shift from their original location to other areas of the inferior vena cava or even the heart. Retrieving a migrated filter, especially if it’s within the heart, can be dangerous, often necessitating major heart surgery.
• IVC perforation: On occasion, IVC filters can puncture the wall of the inferior vena cava, either immediately upon deployment or at a later date. A 2016 study noted that a significant portion of IVC filter complications were related to vein perforations. Usually, patients don’t experience symptoms unless the struts also damage other organs outside the IVC. Potential damages could include the duodenum or even the aorta.
• Filter Fracture: This is when the struts detach from the device. It is most frequently seen in filters that have been in place for more than 12 months. This occurs in roughly one to two percent of filters after long-term use, making it a frequently reported issue with retrievable IVC filters. These broken parts have the ability to travel through other blood vessels that lead to the renal veins, heart, and lungs.

Complications during IVC filter removal can differ based on the filter model. Severe issues, such as migration, perforation, and organ injury, have been documented in IVC filter lawsuits against specific device manufacturers.

The risk of complications during the filter retrieval process increases the longer a filter remains implanted. If the filter has shifted or implanted into the vein, removal can become challenging, potentially lengthening the procedure or requiring specialized filter retrieval techniques.

To minimize complications during removal, it is important to remove retrievable IVC filters once the threat of DVT has subsided.

IVC Recalls

Between 2005 and 2019, nearly 145,000 IVC filters were recalled during 5 major recalls. Even with the complications reported to the FDA, manufacturers have rarely initiated these recalls.

Boston Scientific Greenfield IVC Filter

In 2005, Boston Scientific announced 2 recalls for its Greenfield IVC filters.

In December 2005, the firm recalled 18,000 filters because of a flaw that could cause the carrier capsule to dislodge during implantation. The recall advisory also indicated potential embolism risks to the lungs or heart. The FDA categorized this as a Class I recall—the most serious recall level. 

Previously, in August 2005, another recall was made for the same Greenfield IVC filters. This recall involved two batches that had a faulty delivery mechanism, missing a vital taper. This could lead to vein damage during placement.

Cordis OptEase IVC Filter

In March 2013, Cordis issued a recall for approximately 33,000 OptEase IVC filters. An instruction error meant the devices risked being placed upside down implantation. Cordis sent out a correction notice.

The FDA categorized this as a Class I recall, indicating a substantial chance of leading to severe health issues or even fatalities.

Bard Denali IVC Filter

In March 2015, Bard announced a recall of more than 1,100 Denali IVC filters. The issue was related to missing label warnings. Specifically, the labels lacked advisories against using the devices in patients with ongoing sepsis or a known sensitivity to nickel-titanium alloy.

While there was no need for the devices to be sent back, Bard reached out to the medical professionals who ordered the filters. The company offered replacements for those who were unsatisfied with the original product.

Cook Medical Gunther Tulip IVC Filter

In Feb. 2019, Cook Medical recalled more than 91,000 Gunther Tulip IVC filters. The company identified an error in the filter’s procedure instructions shipped with the device. After the recall, Cook Medical re-issued instructions for the Gunther Tulip IVC filters.

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