The law of unintended consequences: current design challenges in inferior vena cava filters.

INTRODUCTION: Venous thromboembolic disease (VTD) encompassing deep vein thrombosis (DVT) and pulmonary embolism (PE) is a commonly encountered condition with potentially fatal sequelae. When unable to be adequately anticoagulated, patients require a mechanical means to prevent PE. This review discusses the history of inferior vena cava interruption and the development of inferior vena cava filters (IVCF). Areas covered: Milestone innovations in the mechanical treatment of VTD, their successes and shortcomings are discussed. The unforeseen complications that have occurred with implantation of IVCF have a profound impact on the present utilization of retrievable filters. Particular attention is dedicated to the evidence for safe and effective use of IVCF and the challenges presented to further improvement of these technologies. Expert commentary: While evidence suggests that IVCF are effective in preventing PE, the recent 'de-volution' from permanent to retrievable design has unleashed an epidemic device-related complications. Retrievable filter design is reliant on a 'Goldilocks' premise: make the device stable (so it doesn't migrate), but not too stable (so you can still retrieve it). Efforts must be aimed at optimizing utilization using decision support tools, meticulous follow up after deployment, and conversion from retrievable to permanent devices if the patient requires lifelong mechanical prophylaxis.