Long-term follow-up of the Bird's Nest IVC Filter

AIM: This study is a long-term clinical follow-up of the Bird's Nest Filter which addresses issues such as caval patency, filter integrity, morbidity and mortality, MATERIALS AND METHODS: 78 consecutive patients with Bird's Nest Filters ins erted between 1989 and 1994 were recalled for clinical assessment and imagi ng follow-up. Pre- and post-filter medical histories were obtained from the patients and their medical records. They were examined for clinical signs of inferior vena cava occlusion. Imaging follow-up was by plain abdominal r adiography, colour duplex ultrasound and computed tomography. RESULTS: 52 patients were alive and well at 4-6 years. Thirty-day mortality was 5.1%. Three-year mortality was 19.2%. Recurrent pulmonary embolus occu rred in 1.3%. IVC occlusion was demonstrated in 4.7%. No evidence of filter migration was seen, Wire prolapse occurred in 70% on abdominal g-ray and a symptomatic performation of the caval wall in 85.3% on CT. Morbidity and mo rtality were the same whether the patient was anticoagulated or not. CONCLUSION: The Bird's Nest Filter is safe and effective in both the short and long term. Nicholson, A. A. et al. (1999) Clinical Radiology 54, 759-76 4. (C) 1999 The Royal College of Radiologists.