Contemporary Management of Pulmonary Embolism: Review of the Inferior Vena Cava filter and Other Endovascular Devices

Inferior vena cava (IVC) filters and endovascular devices are used to mitigate the risk of pulmonary embolism in patients presenting with lower extremity venous thromboembolism in whom long-term anticoagulation is not a good option. However, the efficacy and benefit of these devices remain uncertain, and controversies exist. This review focuses on the current use of IVC filters and other endovascular therapies in clinical practice. The indications, risks, and benefits are discussed based on current data. Further research and randomized controlled trials are needed to characterize the patient population that would benefit most from these interventional therapies.

Safe endovascular retrieval of a vena cava filter after duodenal perforation

The use of vena cava filters (VCF) is a common procedure utilized in the prevention of pulmonary embolism (PE), yet VCFs have some significant and known complications, such as strut penetration and migration. Deep vein thrombosis (DVT) and PE remain a major cause of morbidity and mortality in the United States. It is estimated that as many as 900,000 individuals are affected by these each year with estimates suggesting that nearly 60,000–100,000 Americans die of DVT/PE each year. Currently, the preferred treatment for DVT/PE is anticoagulation. However, if there are contraindications to anticoagulation, an inferior vena cava (IVC) filter can be placed. These filters have both therapeutic and prophylactic indications. Therapeutic indications (documented thromboembolic disease) include absolute or relative contraindications to anticoagulation, complication of anticoagulation, failure of anticoagulation, propagation/progression of DVT during therapeutic anticoagulation, PE with residual DVT in patients with further risk of PE, free-floating iliofemoral IVC thrombus, and severe cardiopulmonary disease and DVT. There are also prophylactic indications (no current thromboembolic disease) for these filters. These include severe trauma without documented PE or DVT, closed head injury, spinal cord injury, multiple long bone fractures, and patients deemed at high risk of thromboembolic disease (immobilized or intensive care unit). Interruption of the IVC with filters has long been practiced and is a procedure that can be performed on an outpatient basis. There are known complications of filter placement, which include filter migration within the vena cava and into various organs, as well as filter strut fracture. This case describes a 66-year-old woman who was found to have a filter migration and techniques that were utilized to remove this filter.

Ibero-American Society of Interventionism (SIDI) and the Spanish Society of Vascular and Interventional Radiology (SERVEI) Standard of Practice (SOP) for the Management of Inferior Vena Cava Filters in the Treatment of Acute Venous Thromboembolism

Objectives: to present an interventional radiology standard of practice on the use of inferior vena cava filters (IVCFs) in patients with or at risk to develop venous thromboembolism (VTE) from the Iberoamerican Interventional Society (SIDI) and Spanish Vascular and Interventional Radiology Society (SERVEI). Methods: a group of twenty-two interventional radiologist experts, from the SIDI and SERVEI societies, attended online meetings to develop a current clinical practice guideline on the proper indication for the placement and retrieval of IVCFs. A broad review was undertaken to determine the participation of interventional radiologists in the current guidelines and a consensus on inferior vena cava filters. Twenty-two experts from both societies worked on a common draft and received a questionnaire where they had to assess, for IVCF placement, the absolute, relative, and prophylactic indications. The experts voted on the different indications and reasoned their decision. Results: a total of two-hundred-thirty-three articles were reviewed. Interventional radiologists participated in the development of just two of the eight guidelines. The threshold for inclusion was 100% agreement. Three absolute and four relative indications for the IVCF placement were identified. No indications for the prophylactic filter placement reached the threshold. Conclusion: interventional radiologists are highly involved in the management of IVCFs but have limited participation in the development of multidisciplinary clinical practice guidelines.

Why optional inferior vena cava filters are not always retrieved? A real world 19 years experience in a Swiss tertiary care university hospital

BACKGROUND

inferior vena cava filters (IVCF) are widely used to prevent thromboembolic events in patients not suitable for anticoagulation (AC). Although new generations of filters are optional and therefore retrievable, most of them become permanent. Aim of our study was to evaluate real life IVCF management in a tertiary hospital including retrieval rates and reasons for permanent filtering.

MATERIALS AND METHODS

Electronic charts from patients receiving IVCF in a Swiss university hospital, during 1999-2017, were retrospectively identified. Patients were classified in two groups, according to filter retrieval (RG) or not (NRG). Type and reasons of filter placement were assessed. Retrieval, complications, and mortality rates were calculated. Reasons of non-retrieval were analyzed.

RESULTS

920 patients received an IVCF during 1999-2017. Filters were retrieved in 372 patients (40.65%). Subjects in the NRG were significantly older, more chronically ill, and presented higher mortality rate at 12 months following filter insertion (29.60% vs. 4.30%; p < 0.001). Reasons for non-retrieval included lack of follow-up (22.34%), persistent contraindications to AC (20.51%), technical issues (17.40%), and severe morbidity with short life expectancy (17.22%). Overall, complication rates after filter placement was 18.58%. Most reported complication was filter thrombosis (15.60%).

CONCLUSIONS

In a real life setting, optional IVCF are still too often left in place indefinitely. Need for a systematic follow-up to ensure prompt filter retrieval is warranted. IVCF are not retrieved mostly in chronically and more severely ill patients, likely accounting for higher mortality in these subjects.

Is external compression on the IVC a risk factor for IVC filter abutment? A single center experience of 141 infrarenal celect filter insertions

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Tilt of the IVC filter is the major problem for the filter retrieval rate.

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External compression on the IVC wall can cause filter tilting.

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Identifying external compression factors are necessary before insertion of IVC filter.

Objectives

To investigate risk factors for inferior vena cava (IVC) filter abutment, including external compression on the IVC wall, using venous phase computed tomography (CT).

Methods

One-hundred-forty-one cases of Celect IVC filter insertion between January 2009 and April 2017 were retrospectively reviewed. On pre-procedural CT, IVC diameter and morphological classifications were measured. Filter tilt angle, IVC angle, vertical position, and filter tip abutment to the IVC wall were analyzed on post-procedural CT. IVC compression was examined by pre- and post-procedural CT analysis. Multiple logistic regression analysis was conducted to find factors related to IVC filter abutment.

Results

Of 141 IVC filter insertion cases, 52 were classified in the filter tip abutment group and 89 in the non-abutting group. IVC tilt angle (11.7 ± 5.5° vs. 6.4 ± 5.4°), presence of external compression (14/52, 27% vs. 9/89, 9%), and IVC morphology were different between the groups (p < 0.05). In multiple logistic regression analysis, filter-tilt angle over 9.25° and external compression on the IVC were found to be independent predictors of filter abutment (odds ratios: 4.56, 10.18, respectively).

Conclusion

IVC filter tilt, external compression on IVC wall, and IVC morphology were significantly different between the filter tip abutment and non-abutment groups. External compression and filter tilt over 9.25° were risk factors for filter tip abutment in multiple logistic regression analysis. By identifying these factors, we may be able to reduce filter tilting by preventing the filter from being deployed in a dangerous area.

Detailed assessment of benefits and risks of retrievable inferior vena cava filters on patients with complicated injuries: the da Vinci multicentre randomised controlled trial study protocol

INTRODUCTION

Retrievable inferior vena cava (IVC) filters have been increasingly used in patients with major trauma who have contraindications to anticoagulant prophylaxis as a primary prophylactic measure against venous thromboembolism (VTE). The benefits, risks and cost-effectiveness of such strategy are uncertain.

METHODS AND ANALYSIS

Patients with major trauma, defined by an estimated Injury Severity Score >15, who have contraindications to anticoagulant VTE prophylaxis within 72 hours of hospitalisation to the study centre will be eligible for this randomised multicentre controlled trial. After obtaining consent from patients, or the persons responsible for the patients, study patients are randomly allocated to either control or IVC filter, within 72 hours of trauma admission, in a 1:1 ratio by permuted blocks stratified by study centre. The primary outcomes are (1) the composite endpoint of (A) pulmonary embolism (PE) as demonstrated by CT pulmonary angiography, high probability ventilation/perfusion scan, transoesophageal echocardiography (by showing clots within pulmonary arterial trunk), pulmonary angiography or postmortem examination during the same hospitalisation or 90-day after trauma whichever is earlier and (B) hospital mortality; and (2) the total cost of treatment including the costs of an IVC filter, total number of CT and ultrasound scans required, length of intensive care unit and hospital stay, procedures and drugs required to treat PE or complications related to the IVC filters. The study started in June 2015 and the final enrolment target is 240 patients. No interim analysis is planned; incidence of fatal PE is used as safety stopping rule for the trial.

ETHICS AND DISSEMINATION

Ethics approval was obtained in all four participating centres in Australia. Results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12614000963628; Pre-results.

Indications and Outcomes of Open Inferior Vena Cava Filter Removal

BACKGROUND

Despite recommendations for retrieval of inferior vena cava (IVC) filters, most are not removed in a timely manner. Longer IVC filter dwell times are associated with caval wall perforation and tilting that make percutaneous retrieval more difficult. Open IVC filter removal is generally reserved for patients with symptoms referable to the filter, such as chronic back and abdominal pain. We present our management algorithm and review of cases of open IVC filter removal.

METHODS

Patients referred for management of implanted IVC filters from May 2010 to May 2016 were included. Demographic and imaging were reviewed for cases requiring open surgical removal.

RESULTS

There were 221 percutaneous retrieval attempts in 218 patients. Successful retrieval occurred in 196 (89%) attempts. There were 7 patients who had open surgical IVC filter removal after failure of percutaneous retrieval. One patient had 2 filters and another had 3 filters. Except for 1 case with complications during the percutaneous retrieval procedure, the remaining patients all suffered from back or abdominal pain. All had significant filter strut penetration through the caval wall into adjacent structures. Postoperatively, all patients had relief of pain. There were no deaths and 1 patient had a minor ileus that spontaneously resolved.

CONCLUSIONS

Patients who fail percutaneous IVC filter retrieval can expect low morbidity and prompt resolution of symptoms after open surgical removal via minilaparotomy.

Retrievable IVC filters - Friend or foe

Venous thromboembolism is a common condition with widely varied outcomes. Pulmonary embolism is associated with a case-fatality rate of up to 8%, increasing up to 18-fold in massive PE. Pharmacological treatment of VTE with anticoagulant medication (AC) is the first line therapy of choice. Retrievable inferior vena cava filters (IVCF) are indicated as a short-term replacement for AC in certain circumstances. Most of the evidence concerning IVCF pertains to permanent filters and older filter models. Limited evidence for retrievable IVCF results in poor consensus regarding indications, follow-up and retrieval. Complications increase with dwell-time and retrieval success rates decline. Professional bodies advocate strict guideline adherence and robust strategies for filter monitoring to maximise retrieval rate.

Percutaneous Removal of Filter-Induced Iliocaval Thrombus Using the AngioVac Device

Most percutaneous mechanical thrombectomy devices entail thrombolysis and/or thrombus fragmentation followed by subsequent aspiration, with the associated risks of bleeding and embolization. We describe the use of the AngioVac system (Angiodynamics, Latham, NY USA) for extraction of extensive iliocaval thrombus associated with an inferior vena cava filter followed by percutaneous inferior vena cava filter extraction in a patient with an absolute contraindication to thrombolysis. The AngioVac may be considered in this scenario as it does not require thrombolytics and can remove whole thrombus, thus overcoming some of the limitations of percutaneous mechanical thrombectomy devices in the setting of subacute and early chronic thrombus.

Clinician-performed ultrasound in hemodynamic and cardiac assessment: a synopsis of current indications and limitations

Accurate hemodynamic and intravascular volume status assessment is essential in the diagnostic and therapeutic management of critically ill patients. Over the last two decades, a number of technological advances were translated into a variety of minimally invasive or non-invasive hemodynamic monitoring modalities. Despite the promise of less invasive technologies, the quality, reliability, reproducibility, and generalizability of resultant hemodynamic and intravascular volume status data have been lacking. Since its formal introduction, ultrasound technology has provided the medical community with a more standardized, higher quality, broadly applicable, and reproducible method of accomplishing the above-mentioned objectives. With the advent of portable, hand-carried devices, the importance of sonography in hemodynamic and volume status assessment became clear. From basic venous collapsibility and global cardiac assessment to more complex tasks such as the assessment of cardiac flow and tissue Doppler signals, the number of real-life indications for sonology continues to increase. This review will provide an outline of the essential ultrasound applications in hemodynamic and volume status assessment, focusing on evidence-based uses and indications.

Comparison of complication rates associated with permanent and retrievable inferior vena cava filters: a review of the MAUDE database

PURPOSE

To compare the safety of permanent and retrievable inferior vena cava (IVC) filters by reviewing the U.S. Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database.

MATERIALS AND METHODS

The MAUDE database was reviewed from January 1, 2009, to December 31, 2012. Product class search criteria were "filter, intravascular, cardiovascular." Type of device used and specific adverse events (AEs) were recorded.

RESULTS

For the period January 2009-December 2012, 1,606 reported AEs involving 1,057 IVC filters were identified in the MAUDE database . Of reported AEs, 1,394 (86.8%) involved retrievable inferior vena cava filters (rIVCFs), and 212 (13.2%) involved permanent inferior vena cava filters (pIVCFs) (P < .0001). Reported AEs included fracture, migration, limb embolization, tilt, IVC penetration, venous thromboembolism and pulmonary embolism, IVC thrombus, and malfunctions during placement. Each specific AE was reported with significantly higher frequency in rIVCFs compared with pIVCFs. The most common reported complication with rIVCFs was fracture, whereas the most commonly reported complications with pIVCFs were placement malfunctions. For rIVCFs, the most commonly reported AE varied depending on filter brand.

CONCLUSIONS

The MAUDE database reveals that complications occur with significantly higher frequency with rIVCFs compared with pIVCFs. This finding suggests that the self-reported complication rate with rIVCFs is significantly higher than the self-reported complication rate with pIVCFs.

Incidence and risk factors for fatal pulmonary embolism after major trauma: a nested cohort study

BACKGROUND

Venous thromboembolism is common after major trauma. Strategies to prevent fatal pulmonary embolism (PE) are widely utilized, but the incidence and risk factors for fatal PE are poorly understood.

METHODS

Using linked data from the intensive care unit, trauma registry, Western Australian Death Registry, and post-mortem reports, the incidence and risk factors for fatal PE in a consecutive cohort of major trauma patients, admitted between 1994 and 2002, were assessed. Non-linear relationships between continuous predictors and risk of fatal PE were modelled by logistic regression.

RESULTS

Of the 971 consecutive trauma patients considered in the study, 134 (13.8%) died after their injuries. Fatal PE accounted for 11.9% of all deaths despite unfractionated heparin prophylaxis being used in 44% of these patients. Fatal PE occurred in those who were older (mean age 51- vs 37-yr-old, P=0.01), with more co-morbidities (Charlson's co-morbidity index 1.1 vs 0.2, P=0.01), had a larger BMI (31.8 vs 24.5, P=0.01), and less severe head and systemic injuries when compared with those who died of other causes. Sites of injuries were not significantly related to the risk of fatal PE. Fatal PE occurred much later than deaths from other causes (median 18 vs 2 days, P=0.01), and the estimated attributable mortality of PE was 49% (95% confidence interval 36-62%).

CONCLUSIONS

Fatal PE appeared to be a potential preventable cause of late mortality after major trauma. Severity of injuries, co-morbidity, and BMI were important risk factors for fatal PE after major trauma.

Complications Associated with Pulmonary Artery Catheters: A Comprehensive Clinical Review

Care for the critically ill patient requires maintenance of adequate tissue perfusion/oxygenation. Continuous hemodynamic monitoring is frequently utilized to achieve these objectives. Pulmonary artery catheters (PAC) allow measurement of hemodynamic variables that cannot be measured reliably or continuously by less invasive means. Inherent to every medical intervention are risks associated with that intervention. This review categorizes complications associated with the PAC into four broad groups — Complications of central venous access; complications related to PAC insertion and manipulation; complications associated with short- or long-term presence of the PAC in the cardiovascular system; and errors resulting from incorrect interpretation/use of PAC-derived data. We will discuss each of these four broad categories, followed by in-depth descriptions of the most common and most serious individual complications.