BACKGROUND: Inferior vena caval filters are a recognized intervention for recurrent pulmonary embolism (PE). Filter utilization in the UK is considerably less than in Europe; this may partly be due to omission of referral of appropriate patients. METHODS: A cohort with the prospect of benefit from caval filter insertion was identified by retrospective study of inpatients who died within 30 days of a positive ventilation-perfusion (V/Q) scan over 2 years. The number of actively managed patients in this group who fulfilled the recognized criteria for caval filter insertion was determined. RESULTS: Fifty-two of 606 patients died within 30 days of scanning. Information was available on 38 (73 per cent) of 52 who had 39 scans (14 positive, 22 negative, three indeterminate). Six of 14 patients (two men and four women, aged 46-84 years) with a positive scan had strong indications for caval filter deployment including contraindication to anticoagulation (three), recurrent PE despite adequate anticoagulation (two) and complications arising from anticoagulation (one). All six died following continuing embolism or complications from anticoagulation. CONCLUSION: Six of 14 patients who died following acute PE required caval filtration but were not offered this intervention. Failure to refer patients who would benefit from filtration may partially account for the disparity in utilization of caval filters between the UK and Europe. Furthermore, because of the choice of death as outcome marker, this study underestimated the value of caval filter utilization.