Twenty-year clinical experience with the Greenfield filter.

The purpose of this study was to characterize the long-term safety and efficacy of the stainless-steel Greenfield filter. All patients who underwent Greenfield filter placement at three institutions during tenure of the senior author (L.J.G.) were entered prospectively into a filter registry and followed on an annual basis. Follow-up consisted of clinical examination to evaluate the status of venous disease or recurrence of pulmonary embolism, abdominal radiographs to determine the stability of the filter and an evaluation of the patency of the inferior vena cava and lower extremities. This report summarizes the 20-year experience. The rate of recurrent pulmonary embolism was 4% and the caval patency rate was 96%. Some filter movement of no clinical significance was seen in 8% of cases. There was no procedural mortality and morbidity was minimal. Greenfield filter insertion provides long-term protection from pulmonary embolism while preserving caval patency.