Retrievable and Permanent Inferior Vena Cava Filters: Selected Considerations

Optional Vena Cava Filters: What, Why, and When

Optional vena cava filters can used to provide either short-term or permanent protection from pulmonary embolism. These devices have recently become available for clinical use in the United States. However, there remains a paucity of data about these devices and their outcomes. This article reviews current and future devices, the rationale behind non-permanent caval filtration, and the generally accepted guidelines for their clinical application.

Penetration of an inferior vena cava filter into the aorta

Transvenous placement of inferior vena cava (IVC) filters is commonly performed in selected patients with deep venous thrombosis and pulmonary embolism. However, filter placement is sometimes associated with serious complications. A common complication is asymptomatic perforation of the IVC and penetration of adjacent organs by the filter. Here, we report a case of an 83-year-old man whose prophylactic IVC filter penetrated the aorta. The patient was closely followed without surgical intervention for more than a year, and no additional complications were observed.

Rates and predictors of plans for inferior vena cava filter retrieval in hospitalized patients

BACKGROUND

Use of inferior vena cava (IVC) filters has been increasing over time. However, because of the increased risk of deep vein thrombosis with permanent filters, placement of retrievable filters has been recommended. Little is known about the factors associated with planned retrieval of IVC filters.

OBJECTIVE

To describe rates and predictors of plans to retrieve IVC filters in hospitalized patients.

DESIGN

We identified all IVC filter placements from 2001-2006 at an academic medical center and reviewed medical charts to obtain data about patient characteristics, filter retrieval plans, and retrieval success rates. Multivariable logistic regression was used to identify independent predictors of planned filter retrieval in patients with retrievable filters.

RESULTS

Out of 240 patients who underwent placement of retrievable IVC filters, only 73 (30.4%) had documented plans for filter retrieval. Factors associated with lower rates of planned filter retrieval included a history of cancer [adjusted odds ratio (OR) and 95% confidence interval 0.2 (0.1-0.5)] and not being discharged on anticoagulants [OR 0.1 (0.1-0.3)]. In addition, 36 (21.6%) of patients without retrieval plans had no contraindications to retrieval. Of the 62 patients who underwent attempted filter retrieval, 25.8% of filters could not be successfully removed.

CONCLUSIONS

Only 30.4% of patients who underwent placement of a retrievable IVC filter had documented plans for filter removal. Although most patients had justifiable reasons for filter retention, 21.6% of patients had no clear contraindications to filter removal. Efforts to improve rates of filter retrieval in appropriate patients may help reduce the long-term complications of IVC filters.

Guidelines and the use of inferior vena cava filters: a review of an institutional experience

BACKGROUND AND OBJECTIVES

Based on the American College of Chest Physicians 2004 antithrombotic therapy for venous thromboembolism (VTE) and the Eastern Association for the Surgery of Trauma 2002 guidelines, placement of an inferior vena cava (IVC) filter is indicated in patients who either have, or are at high risk for, VTE, but have a contraindication or failure of anticoagulation. Our aim is to compare clinical characteristics and outcomes of patients receiving IVC filters within-guidelines (WG) and outside-of-guidelines (OOG).

METHODS

The 558 patients who received an IVC filter were divided into two groups called WG or OOG. The WG group met the criteria described above and the OOG group did not have a contraindication to or a failure of anticoagulation.

RESULTS

The WG group had 362 patients and the OOG group had 196 patients. The OOG group had one (0.5%) patient with post-filter pulmonary embolism (PE), two (1%) with IVC thrombosis, and seven (3.6%) with deep vein thrombosis (DVT). The WG group had five (1.4%) patients with post-filter PE, 13 (3.6%) with IVC thrombosis, and 34 (9.4%) with DVT. All patients who developed post-filter PE had a DVT before filter placement, and patients who did not have a prior VTE event were at a significantly lower risk of developing post-filter IVC thrombosis and PE.

CONCLUSION

Our data do not support the use of an IVC filter outside of guidelines in patients without prior VTE who can tolerate anticoagulation because of the low risk of developing PE.

A prospective observational study of IVC filters in pediatric patients

BACKGROUND

The use of inferior vena cava (IVC) filters to prevent pulmonary embolism (PE) has increased with the advent of retrievable filters (Crowther: Am J Med 120: S13-S17, 2007). Both permanent and retrievable filters have been used in the pediatric population, though reports describing such patients and their outcomes are limited.

PROCEDURE

Our center has established a longitudinal prospective cohort study of consecutive patients with acute venous thromboembolism (VTE) at our pediatric tertiary care institution. Data collection in this study includes medical history, risk factors, radiologic and laboratory studies, therapy, and follow-up.

RESULTS

Two hundred ten patients were enrolled into this cohort from January 2003 to January 2007. IVC filters were percutaneously placed into 11 patients, ranging in age from 6.8 to 23.4 years. The primary reason for filter placement was a VTE and a contraindication to anticoagulation. Nine patients had retrievable filters placed and two received permanent filters. Seven of the nine retrievable filters were removed 21-97 days (median 37 days) after placement. In the remaining two patients, thrombus prevented removal in one, and the filter was electively retained in the other. One patient with a permanent filter died from malignancy. The three patients who are alive and well with IVC filters have had them for 25-60 months. No patient with an IVC filter developed a subsequent PE.

CONCLUSIONS

Approximately 5% of patients in this pediatric thrombosis cohort received an IVC filter. The placement and removal of these devices is technically feasible in children.

Inferior vena cava filters in the management of venous thromboembolism

Inferior vena cava (IVC) filters, both retrievable and permanent, are indicated for the prevention of pulmonary embolism (PE) in patients contraindicated for anticoagulant therapy, in those with anticoagulant therapy complications, and perhaps for those with recurrent PE despite therapeutic anticoagulation. Because of the lack of randomized controlled trials (only 1 has been published), clinicians have little evidence-based information to assist them in determining proper use of IVC filters. The introduction of retrievable filters and the ease of insertion have stimulated increased use of these devices without strong evidence or follow-up to assess either efficacy or longer-term clinical outcomes. Current evidence-based guidelines recommend IVC filter insertion only in patients with proven venous thromboembolism and an absolute contraindication for anticoagulation.