Researchers find better management needed for use of IVC filters

March 18, 2013, Boston University Medical Center

Researchers from Boston University School of Medicine (BUSM) have found that the use of Inferior Vena Cava (IVC) filters for the prevention and treatment of venous thrombotic events (VTE) may result in poor outcomes due to mechanical filter complications—largely due to low filter retrieval rates and inconsistent use of anticoagulants—and high rates of venous thromboembolism. The study, which was conducted at New England's largest trauma center, Boston Medical Center (BMC), currently appears on-line in JAMA Internal Medicine and is believed to be one of the first to retrospectively review retrieval options of IVC filters.

In response to this study, BMC is now using a multi-disciplinary team approach to achieve the tracking and timely retrieval of these filters, incorporating specialists from vascular surgery, interventional radiology, cardiology and hematology. BMC is one of a small group of hospitals nationwide to define and address the problem, as well as implement a system to tackle this national safety issue.

are used to prevent pulmonary embolism, a potentially fatal condition where a blood clot breaks off from one of the large veins in the legs and lodges in the lungs. They are generally used only when people are unable to safely receive blood thinning medications. Most filters are designed to be temporary, meaning that they should be removed when the risk of pulmonary embolism has subsided.

National data has shown that many IVC filters are left in place indefinitely. Despite a lack of randomized, controlled trials demonstrating their long-term safety and efficacy, the use of IVC filters continues to increase each year.

In the study, a review of IVC filter usage between August 2003 and February 2011 was conducted at BMC. During that timeframe, IVC filters were placed in 978 patients. Charts were reviewed to determine the indication for filter placement, use of anticoagulant medication, complications resulting from filter placement and details regarding patient follow up and filter retrieval.

Of 679 potentially retrievable IVC filters inserted, only 8.5 percent were successfully removed. Unsuccessful retrieval attempts were made in 18 percent of patients. VTEs occurred in 7.8 percent of patients after filter placement, including 25 pulmonary emboli, all of which occurred with the filter in place. Forty-eight percent of VTEs were in patients without at the time of filter placement and 89 percent occurred in patients without anticoagulation. Many filters placed after trauma, were inserted when the highest bleeding risk had subsided and anticoagulation may have been more appropriate. While many of these filters were placed due to a perceived contraindication to anticoagulation, 25 percent of patients were discharged on therapeutic anticoagulation.

According to the researchers, more than 259,000 filters were inserted in 2012 and while many professional groups have guidelines regarding filter insertion, they vary widely and often conflict. The American College of Radiology and Society of Interventional Radiology Guidelines state that a filter can be placed as prophylaxis for any patient at high-risk of developing deep venous thrombosis (DVT) or , while the American College of Chest Physicians guidelines recommend against an IVC filter unless the patient has an acute proximal lower extremity DVT and cannot be anticoagulated. "These conflicting guidelines reflect the absence of good quality data to guide clinical practice," explained senior author J. Mark Sloan, MD, an assistant professor of medicine at BUSM and a hematologist/oncologist at BMC.

Sloan stresses that this study highlights the importance of an institution developing a proper protocol for the safe retrieval of these filters. "As a result of these findings, a 'filter insertion procedure note' that specifies the indication for filter placement and the anticipated duration of placement is now mandatory for all IVC filter insertions at BMC. Patients are also given educational material after filter placement stating that most filters should be removed once the risk for has subsided or anticoagulation is tolerated."

At BMC, every IVC filter is now promptly entered into a central interdepartmental registry and tracked until retrieval. In addition, for filters not deemed permanent at the time of insertion, a designated administrator schedules timely retrieval or a clinic visit specifically to assess for the appropriateness and timing of retrieval. Since this new protocol went into effect at BMC, 47 filters have been inserted. Of the 36 eligible for retrieval, 10 have been successfully retrieved. However, not all patients whose filters are currently in the BMC database are eligible for retrieval at this time.

Another example of the hospital's commitment to this important issue was a BMC patient safety grant that was awarded to Dr. Jeffrey Kalish, BMC's Director of Endovascular Surgery, for his work titled "Retrieval of IVC to decrease associated complications".

"BMC is leading the way to improve safety for our patients," said Stanley Hochberg, MD, senior Vice President for Quality, Safety and Technology and Chief Quality Office at BMC. "Our leadership in this area will prove invaluable for all patients and may become the model for other institutions to follow," he concluded.

Explore further: IVC filters confirmed effective for patients at embolism risk

Related Stories

IVC filters confirmed effective for patients at embolism risk

June 21, 2012
(HealthDay) -- Inferior vena cava (IVC) filters are safe for use in patients at higher risk for venous thromboembolic events (VTEs) while undergoing major spinal surgery, according to research published in the June issue ...

Medical societies to launch large-scale study on vein filter use

February 1, 2013
The Society of Interventional Radiology and Society for Vascular Surgery jointly will launch PRESERVE—the first large-scale, multispecialty prospective study to evaluate the use of inferior vena cava (IVC) filters and related ...

Vena cava filters do not lower mortality rate in most embolism cases

May 31, 2012
A filter used to block clots from passing from the veins in the legs to the arteries of the lung does not improve mortality rates for most patients suffering a pulmonary embolism. However, if a patient is unstable – ...

Cancer patients with blood clots gain no benefit from adding IVCF to fondaparinux

July 7, 2011
Cancer patients with blood clots -- which occur in one of every 200 cancer patients and are the second most common cause of death among cancer patients -- gain no benefit from the insertion of an inferior vena cava filter ...

Recommended for you

A nanoparticle inhalant for treating heart disease

January 18, 2018
A team of researchers from Italy and Germany has developed a nanoparticle inhalant for treating people suffering from heart disease. In their paper published in the journal Science Translational Medicine, the group describes ...

Starting periods before age of 12 linked to heightened risk of heart disease and stroke

January 15, 2018
Starting periods early—before the age of 12—is linked to a heightened risk of heart disease and stroke in later life, suggests an analysis of data from the UK Biobank study, published online in the journal Heart.

'Decorated' stem cells could offer targeted heart repair

January 10, 2018
Although cardiac stem cell therapy is a promising treatment for heart attack patients, directing the cells to the site of an injury - and getting them to stay there - remains challenging. In a new pilot study using an animal ...

Two simple tests could help to pinpoint cause of stroke

January 10, 2018
Detecting the cause of the deadliest form of stroke could be improved by a simple blood test added alongside a routine brain scan, research suggests.

Exercise is good for the heart, high blood pressure is bad—researchers find out why

January 10, 2018
When the heart is put under stress during exercise, it is considered healthy. Yet stress due to high blood pressure is bad for the heart. Why? And is this always the case? Researchers of the German Centre for Cardiovascular ...

Heart-muscle patches made with human cells improve heart attack recovery

January 10, 2018
Large, human cardiac-muscle patches created in the lab have been tested, for the first time, on large animals in a heart attack model. This clinically relevant approach showed that the patches significantly improved recovery ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.