Long term follow-up of transcatheter embolization with autologous clot, oxycel and gelfoam in domestic swine.

Transcatheter embolization of the distal gastrosplenic artery as well as the distal right renal artery or one of its bifurcational branches was performed in 9 domestic swine. The animals were embolized with fresh autologous clot, oxycel or gelfoam in groups of 3. The embolic material was opacified with tantalum in several animals. At 4 months, none of the initial occlusions was sustained and recanalization without residuals was found in the left gastroepipolic artery with only one minor exception. Organized thrombi as sole vascular residuals regardless of embolic substance were found in both the terminal splenic artery as well as in the right renal artery distribution in various degrees together with infarcts in both organs. No trace of either oxycel or gelfoam remained, nor tissue reaction against either material. All 3 agents are therefore regarded equivalent in their long term effects and are not suitable for permanent vascular occlusion.