EVALUATION OF MAXIMUM NEOINTIMA PROLIFERATION AND PLAQUE MORPHOLOGY IN ILIAC SELF-EXPANDING NITINOL STENTS WITH INTRAVASCULAR SONOGRAPHY

OBJECTIVE. The purpose of this study was to use intravascular sonograp hy to evaluate neointima formation, plaque location, and the performan ce of self-expanding nitinol (Memotherm) stents in iliac arteries. SUB JECTS AND METHODS. Seventeen patients (mean age, 64 +/- 9.4 years) wit h stenoses or occlusions of the common (n = 12) or external (n = 5) il iac artery were treated with 21 Memotherm stents (mean diameter +/- SD , 8.9 +/- 1.3 mm; mean length, 53 +/- 20.9 mm). Four patients had two stents each. Intravascular sonography was performed 13 +/- 6 months af ter stent implantation. Maximum thickness of neointima and maximum cro ss-sectional plaque area were measured. Qualitative analysis of plaque composition and lesion topography were also assessed, RESULTS. Intrav ascular sonography revealed 22.1% +/- 17.3% maximum percentage of rest enosis, and maximum plaque area was found to be 11.2 +/- 10 mm(2). Onl y hypoechogenic in-stent lesions (soft plaques) were found. Seven (33% ) incomplete stent expansions and two (10%) incomplete appositions of the stent to the vessel wall were revealed by intravascular sonography . CONCLUSION. Iliac artery Memotherm stents generally showed moderate in-stent restenosis with uniform neointima distribution. Incomplete st ent expansion was detected in one third of all implanted stents.