Greenfield vena caval filter experience: late results in 156 patients.

In a review of clinical experience with the Greenfield filter in 156 patients, the most common indication for insertion was a contraindication to anticoagulation or recurrent embolism during treatment. Most of the filters (86%) were placed infrarenal, with 7% placed intentionally suprarenal and 7% misplaced but amenable to retrieval. Recurrent embolism was suspected in three patients (2%) on the basis of symptoms and was diagnosed by scan in three patients (2%). Follow-up studies on 119 local patients (11 were lost, 49 died) extended to 63 months (average, 23 months) and showed no migration or deaths due to recurrent embolism. Of 102 venacavograms obtained, occlusion of the cava was seen in only three patients (5%), for a long-term patency rate of 95%.