(Deep Vein Thrombosis / Pulmonary Emboli)
Inferior vena cava filters (IVCF) are designed to prevent an often fatal condition known as pulmonary embolism (PE). PE is caused by migration of a large blood clot arising from deep veins of the legs, a condition known as deep vein thrombosis (DVT). Every year in the United States, approximately 600,000 patients develop a PE and between 120,000 - 150,000 are fatal.
Inferior Vena Cava Filters
With the introduction of the Greenfield IVCF in 1973, physicians had the option of implanting a filter in the inferior vena cava to prevent potentially deadly pulmonary embolisms. Initially this filter was implanted surgically and designed as a permanent implant.
With the advent of new medical technology and new biomaterials, IVCF’s have evolved. Most notably, improvements included filters that could be delivered using minimally invasive techniques, (through small catheters) and subsequently removed from the patient (optional filters). Optional filters first approved by the FDA in 2003 have the advantage that they can be left in permanently, or at the physician’s discretion, retrieved at a later date.
While currently approved IVC filters are very effective at preventing PE, incidence of IVCF tilting (potentially making device retrieval impossible), migration and penetration through the wall of the inferior vena cava have been reported.
Source: Johnson, MS. "Retrievable and Permanent IVC Filter; Indications, Use, Results.", ISET Presentation, January 2006, Indiana University School of Medicine.