Clinical evaluation of retrievable inferior vena cava filters for the prevention of pulmonary thromboembolism

A Multidisciplinary Quality Improvement Project Leads to Improved Patient Follow-up and Filter Retrieval Rate

BACKGROUND

To identify risk factors for loss to follow-up after inferior vena cava (IVC) filter placement in inpatients of other departments (IODs) and to determine whether a quality improvement project launched at our institution in April 2022 improved follow-up and filter retrieval rates in these patients.

METHODS

Consecutive patients who underwent retrievable filter placement at our institution between March 2021 and March 2023 were included in this study. Patients were divided into preimprovement (before April 2022; n = 81) and postimprovement (after April 2022; n = 77) groups. Risk factors for loss to follow-up were assessed in the preimprovement group, and filter retrieval rates were compared between groups.

RESULTS

Acute cerebral hemorrhage (OR = 5.745; 95% CI: 1.471-22.434) and lack of requirement for follow-up by the referring department (OR = 3.435; 95% CI: 1.035-11.398) were identified as independent risk factors for loss to follow-up. The filter retrieval rate was higher in the postimprovement group (94.8%) than in the preimprovement group (69.1%; P < 0.001). The rate of loss to follow-up was lower in the postimprovement group (5.2%) than in the preimprovement group (30.9%; P < 0.001). The preimprovement group had a higher incidence of IVC perforation (9.6%) than the postimprovement group (0; P = 0.019) at the time of filter retrieval.

CONCLUSION

Acute cerebral hemorrhage and lack of requirement for follow-up by the referring department are independent risk factors for loss to follow-up among IODs. The quality improvement project at our institution improved follow-up and IVC filter retrieval rates in IODs.

A change in strategy for filter choice leads to improved filter retrieval rates

OBJECTIVE

To assess whether a new strategy for the choice of inferior vena cava filter placed would improve filter retrieval rates at our institution.

METHODS

Consecutive patients who underwent retrievable filter placement for temporary embolic protection between January 2021 and January 2023 were considered for study inclusion. Risk factors for nonretrieval of short-term filters were identified in patients receiving filters between January 2021 and January 2022 (prestrategy group). For patients treated between February 2022 and January 2023 (poststrategy group), a long-term filter was recommended for those with these risk factors, and a short-term filter was recommended for those without these risk factors.

RESULTS

The study population included 303 patients (prestrategy group, n = 154; poststrategy group, n = 149). Long-term immobilization (odds ratio [OR] = 38.000; 95% confidence interval [CI]: 6.858-210.564), active cancer (OR = 17.643; 95% CI: 5.462-56.993), and venous thromboembolism detected in the intensive care unit (OR = 28.500; 95% CI: 7.419-109.477) were identified as independent risk factors for nonretrieval of short-term filters. The total retrieval rate was significantly higher in the poststrategy group (87.2%) than in the prestrategy group (72.7%; P = 0.002); the short-term filter retrieval rate was also significantly higher in the poststrategy group (84.5%) than in the prestrategy group (68.5%; P < 0.001).

CONCLUSION

The proposed strategy for filter choice based on risk factors for short-term filter nonretrieval can accurately identify patients who need long-term filter placement while also increasing the retrieval rates for both short-term filters retrieval rates and overall retrieval rates.

The application of inferior vena cava filters in orthopaedics and current research advances

Deep vein thrombosis is a common clinical peripheral vascular disease that occurs frequently in orthopaedic patients and may lead to pulmonary embolism (PE) if the thrombus is dislodged. pulmonary embolism can be prevented by placing an inferior vena cava filter (IVCF) to intercept the dislodged thrombus. Thus, IVCFs play an important role in orthopaedics. However, the occurrence of complications after inferior vena cava filter placement, particularly recurrent thromboembolism, makes it necessary to carefully assess the risk-benefit of filter placement. There is no accepted statement as to whether IVCF should be placed in orthopaedic patients. Based on the problems currently displayed in the use of IVCFs, an ideal IVCF is proposed that does not affect the vessel wall and haemodynamics and intercepts thrombi well. The biodegradable filters that currently exist come close to the description of an ideal filter that can reduce the occurrence of various complications. Currently available biodegradable IVCFs consist of various organic polymeric materials. Biodegradable metals have shown good performance in making biodegradable IVCFs. However, among the available experimental studies on degradable filters, there are no experimental studies on filters made of degradable metals. This article reviews the use of IVCFs in orthopaedics, the current status of filters and the progress of research into biodegradable vena cava filters and suggests possible future developments based on the published literature by an electronic search of PubMed and Medline databases for articles related to IVCFs searchable by October 2022 and a manual search for citations to relevant studies.

Long-Term Outcomes in Patients with Not-Retrieval Inferior Vena Cava Filter Under Anticoagulation

Since permanent inferior vena cava (IVC) filters increase deep vein thrombosis (DVT), filter retrieval should be performed as possible. Despite the guideline recommendation, IVC filters are not always retrieved in clinical practice. To date, many patients with not-retrieval IVC filters have been prescribed anticoagulant therapy, but the long-term prognosis, including venous thromboembolism (VTE) and bleeding events, remains unknown. In this study, 195 patients who underwent IVC filter implantation between 2006 and 2017 at 3 institutions in Niigata City have been investigated about their deaths, VTE recurrence, and bleeding events. After peaking 2009, the number of IVC filter implantation gradually decreased. During observational period, there were 158 patients with not-retrieval IVC filters (the overall retrieval rate of 19.0%). The not-retrieval group included significantly older and more patients with cancer compared to the retrieval group. Anticoagulation therapy was continued in 88% of the not-retrieval group. During a mean follow-up of 5.0 years, 6 symptomatic DVT events associated with inadequate control of anticoagulation and 13 bleeding events were observed. A total of 52 patients died and only the presence of cancer was prognostic risk factor. Although long-term anticoagulation therapy may be associated with bleeding events, there were few recurrent VTE under optimal anticoagulation. It is anticipated that even if the IVC filter cannot be retrieved, appropriate anticoagulation is useful for prevention of DVT recurrence despite the risk of bleeding.