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


METHODS
78 consecutive patients with Bird's Nest Filters inserted between 1989 and 1994 were recalled for clinical assessment and imaging 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 radiography, 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 occurred in 1.3%. IVC occlusion was demonstrated in 4.7%. No evidence of filter migration was seen. Wire prolapse occurred in 70% on abdominal X-ray and asymptomatic performation of the caval wall in 85.3% on CT. Morbidity and mortality were the same whether the patient was anticoagulated or not.


CONCLUSIONS
The Bird's Nest Filter is safe and effective in both the short and long term.
Nicholson
A A
AA
Radiology Department, Royal Hull Hospitals Trust, Kingston upon Hull, UK.
Ettles
D F
DF
Paddon
A J
AJ
Dyet
J F
JF
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D011859:Radiography; D016896:Treatment Outcome; D016306:Vena Cava Filters
D000925:Anticoagulants