Arterial regeneration over polydioxanone prostheses in the rabbit
H. P. Greisler, J. Ellinger, T. H. Schwarcz, J. Golan, R. M. Raymond and D. U. Kim
We analyzed histologic, ultrastructural, and functional characteristics of
rabbit aortic conduits regenerated over absorbable polydioxanone
prostheses. Twenty-eight polydioxanone-elicited prosthesis/tissue complexes
harvested two weeks to 12 months following implantation were analyzed
grossly; photographed; sectioned for light, scanning, and transmission
electron microscopy; and studied for compliance, bursting strength, and
prostacyclin and thromboxane metabolite contents. No aortic-related deaths
or hemorrhages occurred. Smooth regenerated conduits without stenoses were
seen in 27 of 28 specimens, with one small aneurysm. Transprosthetic
myofibroblast migration and proliferation paralleled the kinetics of
macrophage-mediated prosthetic dissolution, which was consequently delayed
compared with polyglycolic acid prostheses. Confluent endothelial-like
luminal surfaces were present after two weeks. Progressive inner capsular
thickening ended after three months at 420 micron. Ex vivo compliance
curves resembled arterial elasticity. Regenerated tissue withstood 1200 mm
Hg of systolic pressure, and 6-keto-prostaglandin F1 alpha to thromboxane
B2 ratios did not differ from normal control specimens.
