IVC FILTER TILT AND ASYMMETRY - COMPARISON OF THE OVER-THE-WIRE STAINLESS-STEEL AND TITANIUM GREENFIELD IVC FILTERS

PURPOSE: A comparison of tilting, caval coverage, asymmetry, and inser tion problems with the over-the-wire stainless-steel and titanium vers ions of the Greenfield filter. MATERIALS AND METHODS: The study compar ed 104 stainless-steel and 141 titanium Greenfield inferior vena cava (IVC) filter insertions, The angle the sheath and deployed filter made relative to the cava, as well as filter strut distribution, were dete rmined from spot films, The proportionate caval coverage was computed from the cavogram (anteroposterior projection), Mean filter tilts, sub grouped by insertion site, and caval coverage were compared with the S tudent t test, whereas strut patterns were analyzed with a contingency table. RESULTS: The filter caval and sheath caval angles correlated, The filter caval angles varied with insertion site, but were lowest wi th a right jugular approach, Caval coverage was identical with both de signs, The stainless-steel version resulted in a more uniform distribu tion of struts in comparison with the titanium version, The incidence of insertion problems was not significantly different between the filt er types. CONCLUSIONS: While IVC filter tilting was not improved with the newer design, the pattern of struts was more uniformly symmetric w ith the stainless-steel device, The right jugular insertion site was a ssociated with the lowest filter caval angles and the most symmetric p attern of struts.