Although inferior vena cava filter placement may reduce the risk of subsequent acute pulmonary embolism, the treatment may not improve mortality and could be associated with increased deep vein thrombosis among patients with venous thromboembolism, according to a narrative review of clinical trials and meta-analyses.
Acute pulmonary embolism (APE) remains a major contributor to morbidity and mortality despite increasing prophylaxis for deep vein thrombosis (DVT). Inferior vena cava (IVC) filters are designed to prevent thrombus migration from the lower extremities to the pulmonary vasculature and are primarily used in patients with contraindications to anticoagulation or those with hemodynamically unstable APE and poor residual cardiopulmonary reserve.
Evidence Shows Reduced Embolism but No Survival Benefit
Randomized and observational evidence consistently showed fewer PE events with IVC filters but no improvement in survival.
For instance, in the PREPIC trial of 400 patients with proximal DVT, IVC filter placement reduced PE occurrence compared with anticoagulation alone but increased DVT and didn't significantly affect the mortality rate.
Similarly, in the PREPIC 2 trial, which included 399 patients with APE and high-risk DVT receiving anticoagulation for at least 6 months, adding a retrievable IVC filter didn't improve outcomes compared with those in the PREPIC trial.
Meta-analyses reinforced these findings. One analysis found that IVC filters were associated with 0.50 times the likelihood of PE but 1.70 times the likelihood of DVT, with no reduction in APE-related or all-cause mortality.
A separate meta-analysis of 1,274 patients reported lower rates of new PE at 3 months (1% vs 6%) and during follow-up (3% vs 8%), with no statistically significant differences in the rates of new DVT, major bleeding, or mortality between the patients with and without IVC filters.
Potential Benefit in Selected High-Risk Patients
The investigators highlighted that benefits may be more apparent in specific subgroups.
Among patients with recurrent venous thromboembolism receiving anticoagulation, IVC filter placement reduced mortality at 3 months in those with recurrent APE but not in those with uncomplicated recurrent DVT alone.
Observational studies in patients with hemodynamically unstable APE also suggested lower in-hospital mortality with IVC filter placement and intravenous thrombolytic therapy compared with no IVC filter placement, including reductions from 18% to 8% in one analysis and from 48% to 21% in another. However, other studies reported no mortality benefit in similar populations receiving thrombolysis.
In the PRESERVE study of 1,421 patients with 24 months of follow-up, IVC filters were associated with low rates of clinically significant PE and few adverse events. Among patients undergoing removal, nonfatal venous thromboembolism occurred in 7%.
Complications Remain Key Limitation
The investigators emphasized that complications may occur frequently and increase over time.
Early complications included access site bleeding in 6% to 15% of patients and venous thrombosis at the site of insertion in 2% to 35%. Long-term complications included DVT in 4% to 18%, IVC thrombosis in under 10%, and filter fracture in 1% to 2%.
In the PREPIC trial, recurrent DVT occurred in 21% of patients receiving IVC filters compared with 12% of those receiving anticoagulation alone.
Use Has Shifted Toward Therapeutic Indications
IVC filter use in the United States increased through 2010 and declined following US Food and Drug Administration safety communications. Over time, use shifted toward therapeutic indications, increasing from about 71% to 82%.
In the SAFE-IVC study i 270,866 patients, retrieval rates remained low at 15% at a median of 1.2 years and 17% at long-term follow-up, although 94% of removal attempts were successful and carried a low 30-day complications rate.
Guidelines Emphasize Selective Use and Retrieval
Current guidelines recommend IVC filter placement in patients with venous thromboembolism who have contraindications to anticoagulation or recurrence despite therapy, while discouraging routine use in patients eligible for anticoagulation.
The investigators emphasized that filter placement should be paired with structured follow-up and planned retrieval once anticoagulation can be initiated.
“Deployment of the IVC filter remains an important component of interventional APE management within the narrow indications currently proposed,” wrote study authors Joseph P. Hart, MD, and Mark G. Davies, of the Division of Vascular Surgery at the Medical College of Wisconsin.
The study authors reported no conflicts of interest.
Source: Journal of Clinical Medicine
