Late results of suprarenal Greenfield vena cava filter placement.

Placement of the Greenfield filter above the renal veins was necessary in 71 (9%) of 821 total patients in the filter registries of two institutions. The status of 60 patients (85%) could be verified, with follow-up data ranging from 18 months to 16 years (average, 53 months). Of 24 deaths (34%), none was from recurrent embolism or renal failure; death was most commonly associated with a malignant neoplasm. The recurrent embolism rate was 4%, identical to the infrarenal experience. Duplex evaluation of the filters in 22 patients, representing the majority (61%) of living patients, showed that all the filters were patent. Sixteen patients (41%) had lower-extremity edema that predated filter insertion, and in no patient did the results of noninvasive venous studies worsen. Filter fracture (two patients) or distal migration (two patients) had no clinical sequelae, and there was no evidence of renal dysfunction. For thrombus extending to the level of the renal veins or within them and for pregnant patients or women of childbearing age, suprarenal placement of the Greenfield filter is safe and effective, with no filter obstruction seen in follow-up extending to 16 years.