Feature

The ‘Pendulum’ of IVC Filter Use

Benefits of inferior vena cava filter for PE treatment still debatable.

Inferior vena cava filters have emerged as a popular tool to reduce risk for pulmonary embolism. Nevertheless, their use can be a polarizing issue among physicians.

“Many physicians would say that these devices are being used too often, that they are being used for the wrong indications and that they are associated with significant harm,” Ido Weinberg, MD, MSc, FACC, assistant professor of medicine at Massachusetts General hospital, told Cardiology Today’s Intervention.

The advent of new technologies and careful consideration about more appropriate use, however, may help restore balance and lead to a shift in perception among physicians, according to Michael D. Dake, MD, the Thelma and Henry Doelger professor of cardiovascular surgery and medical director of the catheterization and angiography laboratories at Stanford Health Care.

Ido Weinberg

“The pendulum is swinging back toward a more rational view of IVC filters,” he said in an interview. “There is a realization that these devices, when used appropriately, certainly can save lives and are valuable.”

Concerns and Confusion

Guidelines from professional societies generally agree that IVC filter placement is appropriate to reduce risk for PE in patients with acute deep vein thrombosis or PE who have a contraindication to or have failed anticoagulation.

“Beyond this indication, though, there are a lot of discrepancies among the societal recommendations,” John Moriarty, MD, FSIR, director of the IVC filter clinic and associate professor of radiology and medicine at David Geffen School of Medicine at University of California, Los Angeles, said in an interview. “Some societies, for example, recommend a prophylactic indication for patients who are at high risk for DVT or PE due to trauma, cancer or surgery, whereas other societies believe that is overkill and recommend against placing filters in those patients.”

John Moriarty

Unfortunately, this lack of consensus has bred confusion and significantly impacts clinical care, according to Moriarty.

“It causes wide variability in the use of IVC filters across the country and across different health systems,” he said.

For instance, study published in JAMA Internal Medicine in 2013 showed that the use of IVC filters in non-trauma patients with acute venous thromboembolism varied from 0% to 38.96% among 263 hospitals. Additionally, data from a research letter by Mohammed J. Saeed, MBChB, MPH, from the divisions of infectious diseases, department of medicine, Washington University School of Medicine in St. Louis, and colleagues demonstrated that IVC filter placement was higher in the mid-Atlantic region than other areas of the United States.

Many physicians also harbor concerns regarding the safety of IVC filters, experts told Cardiology Today’s Intervention.

IVC filters were initially introduced as permanent methods to intercept blood clots, but the devices themselves were thrombogenic and the risk for complications such as migration and perforation increased over time.

In 2003, the FDA approved the first retrievable IVC filters, which were designed to mitigate some of these risks. After 2003, IVC filter placement increased significantly, according to data from Satyajit Reddy, MD, from the department of internal medicine at Temple University Hospital, Philadelphia, and colleagues published in 2017 in JAMA Internal Medicine.

However, some physicians are uncertain whether the benefits outweigh the risks and have raised questions about potential overuse, especially in light of the available data, according to Weinberg.

Eight-year follow-up data from the randomized PREPIC study, for instance, showed that the addition of a permanent IVC filter to standard anticoagulation reduced PE incidence but increased DVT incidence without any effect on mortality. More recent data from PREPIC2, published in JAMA in 2015, also demonstrated that use of a retrievable IVC filter plus anticoagulation compared with anticoagulation alone did not reduce the risk for symptomatic recurrent PE at 3 months in patients with severe acute PE.

Furthermore, Weinberg noted that most studies place complication rates at about 10%, with most complications being mild.

“Even if you support the use of IVC filters in many contexts, the fact that 1 in 10 patients will experience a complication is not a negligible statistic,” Weinberg said.

The Issue of Removal

In 2010, reports linking retrievable IVC filters to adverse events, such as device migration, filter fracture, an embolization, among others, prompted the FDA to issue a safety communication emphasizing timely removal of retrievable filters when the patient no longer required protection.

After the FDA safety communication, the rate of IVC filter placement decreased by 29%, according to data from Reddy and colleagues. Moreover, although rates varied by geographic region, Saeed and colleagues observed a decline in the percentage of IVC filter placement for prophylactic indications from 2005 to 2014.

“We know from looking at the National Inpatient Sample that the insertion rate of IVC filters peaked in about 2013 and has come down since then, which may be due to the increasing recognition that IVC filters have been overused in some populations,” Moriarty told Cardiology Today’s Intervention.

In 2014, the FDA updated its communication to identify 29 to 54 days after implantation as the appropriate time frame for filter removal.

Nevertheless, many retrievable devices remain in place outside the recommended time window. In the review by Sarosiek and colleagues of 679 patients implanted with retrievable filters, only 8.5% were successfully removed and median retrieval time after placement was 122 days.

“We know that the more quickly IVC filters are removed, the fewer complications occur,” Weinberg said. “If there were a way to improve retrieval rates, we could, in theory, reduce complications.”

However, he noted, uncertainty remains about how to proceed in patients with chronically implanted IVC filters. For patients who have a filter in place that has not been removed but who are not experiencing symptoms and are otherwise healthy, proactive removal may have negative consequences.

“Around the country, there is this fashion of highly involved procedures being used to remove filters that have been in place for many years,” Weinberg said. “In my opinion, it is unnecessary and puts the patients at risk without sufficient benefit. This is a whole aspect of the filter world that people aren’t discussing, and we require more data.”

New Paths Forward

Novel devices, such as the Angel Catheter (BiO2 Medical) and a bioconvertible Sentry filter (Novate Medical), hold promise and may move the field toward safer devices, according to Dake.

“Early retrievable IVC filters were neither fish nor fowl because what makes a good permanent filter doesn’t necessarily make a good retrievable filter,” he said. “Now, we’re seeing different types of devices that are different from the classic temporary retrievable filters.”

Michael D. Dake

The Angel Catheter is an IVC filter that can be inserted and removed through a central venous catheter. Not only could this design help mitigate certain risks to the patient, but it allows any physician who knows how to insert a central catheter to utilize the device, according to Weinberg.

The bioconvertible Sentry filter has a stable frame with filter risk for subsequent IVC occlusion and removes the requirement for filter retrieval, Dake said.

The study results, which Dake presented at VIVA 17, showed that the device was successfully implanted in all 129 patients and no patients experienced a new symptomatic PE at 30 days or 12 months. Freedom from IVC-related complications was 98.2% at 6 months, with no cases of filter tilting, migration, embolization, fracture, IVC perforation or device-related death. Bioconversion also occurred in nearly 96% of patients at 6 and 12 months. Two-year follow-up is currently underway.

“We try to retrieve nearly all IVC filters here at UCLA, but we know that the actual retrieval rate is between 8% and 20% nationally,” Moriarty said. “With a bioconvertible filter, that retrieval rate is effectively made null and void.”

While physicians await more data and even more advances in the technology, they remain concerned about the high IVC filter implantation rates in the United States, particularly when compared with Europe. The decrease that occurred after the FDA communication was only relative and does not fully address the problem, Weinberg said.

Increased education and communication may offer a solution for improving appropriate use of filters as well as retrieval rates, he said.

“Education of physicians on appropriate use is problematic, so many times, filters are requested for questionable indications and there isn’t a healthy discussion about the pros and cons,” Weinberg said. “Registries, like the FDA has, that can provide information on real-world outcomes with filter use could also eventually offer more information about the devices that will result in fewer complications and better utilization.” – by Melissa Foster

Disclosures: Dake reports he receives honoraria from Bard Peripheral Vascular, Cook Medical and W.L. Gore and Associates; consults for Cook Medical, Novate and W.L. Gore and Associates; and receives research funding from Cook Medical, Manta, Novate Medical, Shockwave Medical and W.L. Gore and Associates. Moriarty reports reports he receives grant funding from Angiodynamics and serves on the advisory board for Argon Medical. Weinberg reports he serves on the scientific advisory board for Novate Medical and he is medical director of VASCORE, the Vascular Ultrasound Laboratory.

Inferior vena cava filters have emerged as a popular tool to reduce risk for pulmonary embolism. Nevertheless, their use can be a polarizing issue among physicians.

“Many physicians would say that these devices are being used too often, that they are being used for the wrong indications and that they are associated with significant harm,” Ido Weinberg, MD, MSc, FACC, assistant professor of medicine at Massachusetts General hospital, told Cardiology Today’s Intervention.

The advent of new technologies and careful consideration about more appropriate use, however, may help restore balance and lead to a shift in perception among physicians, according to Michael D. Dake, MD, the Thelma and Henry Doelger professor of cardiovascular surgery and medical director of the catheterization and angiography laboratories at Stanford Health Care.

Ido Weinberg

“The pendulum is swinging back toward a more rational view of IVC filters,” he said in an interview. “There is a realization that these devices, when used appropriately, certainly can save lives and are valuable.”

Concerns and Confusion

Guidelines from professional societies generally agree that IVC filter placement is appropriate to reduce risk for PE in patients with acute deep vein thrombosis or PE who have a contraindication to or have failed anticoagulation.

“Beyond this indication, though, there are a lot of discrepancies among the societal recommendations,” John Moriarty, MD, FSIR, director of the IVC filter clinic and associate professor of radiology and medicine at David Geffen School of Medicine at University of California, Los Angeles, said in an interview. “Some societies, for example, recommend a prophylactic indication for patients who are at high risk for DVT or PE due to trauma, cancer or surgery, whereas other societies believe that is overkill and recommend against placing filters in those patients.”

John Moriarty

Unfortunately, this lack of consensus has bred confusion and significantly impacts clinical care, according to Moriarty.

“It causes wide variability in the use of IVC filters across the country and across different health systems,” he said.

For instance, study published in JAMA Internal Medicine in 2013 showed that the use of IVC filters in non-trauma patients with acute venous thromboembolism varied from 0% to 38.96% among 263 hospitals. Additionally, data from a research letter by Mohammed J. Saeed, MBChB, MPH, from the divisions of infectious diseases, department of medicine, Washington University School of Medicine in St. Louis, and colleagues demonstrated that IVC filter placement was higher in the mid-Atlantic region than other areas of the United States.

PAGE BREAK

Many physicians also harbor concerns regarding the safety of IVC filters, experts told Cardiology Today’s Intervention.

IVC filters were initially introduced as permanent methods to intercept blood clots, but the devices themselves were thrombogenic and the risk for complications such as migration and perforation increased over time.

In 2003, the FDA approved the first retrievable IVC filters, which were designed to mitigate some of these risks. After 2003, IVC filter placement increased significantly, according to data from Satyajit Reddy, MD, from the department of internal medicine at Temple University Hospital, Philadelphia, and colleagues published in 2017 in JAMA Internal Medicine.

However, some physicians are uncertain whether the benefits outweigh the risks and have raised questions about potential overuse, especially in light of the available data, according to Weinberg.

Eight-year follow-up data from the randomized PREPIC study, for instance, showed that the addition of a permanent IVC filter to standard anticoagulation reduced PE incidence but increased DVT incidence without any effect on mortality. More recent data from PREPIC2, published in JAMA in 2015, also demonstrated that use of a retrievable IVC filter plus anticoagulation compared with anticoagulation alone did not reduce the risk for symptomatic recurrent PE at 3 months in patients with severe acute PE.

Furthermore, Weinberg noted that most studies place complication rates at about 10%, with most complications being mild.

“Even if you support the use of IVC filters in many contexts, the fact that 1 in 10 patients will experience a complication is not a negligible statistic,” Weinberg said.

The Issue of Removal

In 2010, reports linking retrievable IVC filters to adverse events, such as device migration, filter fracture, an embolization, among others, prompted the FDA to issue a safety communication emphasizing timely removal of retrievable filters when the patient no longer required protection.

After the FDA safety communication, the rate of IVC filter placement decreased by 29%, according to data from Reddy and colleagues. Moreover, although rates varied by geographic region, Saeed and colleagues observed a decline in the percentage of IVC filter placement for prophylactic indications from 2005 to 2014.

“We know from looking at the National Inpatient Sample that the insertion rate of IVC filters peaked in about 2013 and has come down since then, which may be due to the increasing recognition that IVC filters have been overused in some populations,” Moriarty told Cardiology Today’s Intervention.

In 2014, the FDA updated its communication to identify 29 to 54 days after implantation as the appropriate time frame for filter removal.

PAGE BREAK

Nevertheless, many retrievable devices remain in place outside the recommended time window. In the review by Sarosiek and colleagues of 679 patients implanted with retrievable filters, only 8.5% were successfully removed and median retrieval time after placement was 122 days.

“We know that the more quickly IVC filters are removed, the fewer complications occur,” Weinberg said. “If there were a way to improve retrieval rates, we could, in theory, reduce complications.”

However, he noted, uncertainty remains about how to proceed in patients with chronically implanted IVC filters. For patients who have a filter in place that has not been removed but who are not experiencing symptoms and are otherwise healthy, proactive removal may have negative consequences.

“Around the country, there is this fashion of highly involved procedures being used to remove filters that have been in place for many years,” Weinberg said. “In my opinion, it is unnecessary and puts the patients at risk without sufficient benefit. This is a whole aspect of the filter world that people aren’t discussing, and we require more data.”

New Paths Forward

Novel devices, such as the Angel Catheter (BiO2 Medical) and a bioconvertible Sentry filter (Novate Medical), hold promise and may move the field toward safer devices, according to Dake.

“Early retrievable IVC filters were neither fish nor fowl because what makes a good permanent filter doesn’t necessarily make a good retrievable filter,” he said. “Now, we’re seeing different types of devices that are different from the classic temporary retrievable filters.”

Michael D. Dake

The Angel Catheter is an IVC filter that can be inserted and removed through a central venous catheter. Not only could this design help mitigate certain risks to the patient, but it allows any physician who knows how to insert a central catheter to utilize the device, according to Weinberg.

The bioconvertible Sentry filter has a stable frame with filter risk for subsequent IVC occlusion and removes the requirement for filter retrieval, Dake said.

The study results, which Dake presented at VIVA 17, showed that the device was successfully implanted in all 129 patients and no patients experienced a new symptomatic PE at 30 days or 12 months. Freedom from IVC-related complications was 98.2% at 6 months, with no cases of filter tilting, migration, embolization, fracture, IVC perforation or device-related death. Bioconversion also occurred in nearly 96% of patients at 6 and 12 months. Two-year follow-up is currently underway.

“We try to retrieve nearly all IVC filters here at UCLA, but we know that the actual retrieval rate is between 8% and 20% nationally,” Moriarty said. “With a bioconvertible filter, that retrieval rate is effectively made null and void.”

PAGE BREAK

While physicians await more data and even more advances in the technology, they remain concerned about the high IVC filter implantation rates in the United States, particularly when compared with Europe. The decrease that occurred after the FDA communication was only relative and does not fully address the problem, Weinberg said.

Increased education and communication may offer a solution for improving appropriate use of filters as well as retrieval rates, he said.

“Education of physicians on appropriate use is problematic, so many times, filters are requested for questionable indications and there isn’t a healthy discussion about the pros and cons,” Weinberg said. “Registries, like the FDA has, that can provide information on real-world outcomes with filter use could also eventually offer more information about the devices that will result in fewer complications and better utilization.” – by Melissa Foster

Disclosures: Dake reports he receives honoraria from Bard Peripheral Vascular, Cook Medical and W.L. Gore and Associates; consults for Cook Medical, Novate and W.L. Gore and Associates; and receives research funding from Cook Medical, Manta, Novate Medical, Shockwave Medical and W.L. Gore and Associates. Moriarty reports reports he receives grant funding from Angiodynamics and serves on the advisory board for Argon Medical. Weinberg reports he serves on the scientific advisory board for Novate Medical and he is medical director of VASCORE, the Vascular Ultrasound Laboratory.