Abstract 16063: Impact of Mechanical Factor and Biologic Response on Severe In-Stent Lumen Narrowing in Currently Approved Drug-Eluting Stents
Background: In-stent restenosis can be caused by a combination of exaggerated neointimal proliferation and mechanical factors, such as stent underexpansion and recoil. However, the relative contributions of these factors to follow-up lumen patency have not been systematically evaluated in current drug-eluting stents (DES).
Methods: In 682 patients with serial 3D IVUS, 232 patients showed inadequate lumen at 6–9 months: sirolimus- (SES: 19), everolimus- (EES: 47), paclitaxel- (PES: 67), or zotarolimus- (ZES: 99) eluting stents. According to previous physiologic studies, inadequate follow-up lumen was defined as minimum lumen area < 4.0 mm2. Volumetric data were standardized by length as volume index (VI).
Results: Reference vessel VI was similar among the four DES groups. In patients with inadequate follow-up lumen, SES and EES had smaller stent expansion at post-procedure, as compared with PES and ZES. Stent underexpansion (minimum stent area < 4 mm2) more frequently contributed to inadequate follow-up lumen in SES and EES than in PES and ZES. Delta stent VI, indicating chronic stent recoil, was not significantly different among the four DES. Maximum cross-sectional narrowing (CSN) was greater in PES and ZES, and significant narrowing by neointimal proliferation (max CSN >50%) was more frequently observed in PES and ZES than in SES and EES.
Conclusions: Relative contributions of mechanical versus biological factors to follow-up lumen patency significantly vary among DES platforms, suggesting important implications for current adjunctive mechanical strategy for a given stent design as well as pharmacokinetic properties of next-generation DES technology.
- © 2010 by American Heart Association, Inc.