Abstract 2157: Characteristics of Late Incomplete Stent Apposition: A Comparison between Sirolimus- and Zotarolimus-Eluting Stents
Background: Characteristics of late incomplete stent apposition (LISA) in different DES have not been systematically compared. The aim of this study was to clarify the morphometric parameters of LISA following sirolimus- (SES) and zotarolimus-eluting stents (ZES: RESOLUTE stent).
Method: LISA was defined as separation of at least 1 stent strut from the vessel wall with evidence of blood speckle behind the strut, where post-stent implantation IVUS revealed complete apposition. Nineteen LISA cases (12 SES, 7 ZES) were identified and included in this analysis. A matched corresponding still image at post-procedure was selected for comparison. Vessel (VA), lumen, peri-stent plaque (PA), and stent area were measured in the LISA arc as well as the entire cross-section.
Result: LISA area was significantly larger in SES compared to ZES (2.4±1.5mm2 vs. 1.0±1.0 mm2, p<0.05). Change in VA (Δ VA) of the entire cross-section tended to be larger in SES (3.3±2.8 mm2 vs. 1.0±2.2mm2, p=0.06) and Δ peri-stent PA was not significantly different (1.0±1.5 mm2 vs. 0.4±1.2mm2). Positive vessel remodeling (Δ VA>0) was observed 11 cases in SES and 3 cases in ZES (p=0.05). While VA at LISA arc significantly increased from post-procedure to follow-up in SES, there was no significant difference in ZES (Figure⇓). For the development of LISA, vessel remodeling accounted for 99.8% with SES and 22.9% with ZES (p<0.05), while peri-stent plaque reduction accounted for 2.3% and 53.9% respectively (p<0.05).
Conclusion: LISA area was significantly larger in SES compared to ZES. While vessel remodeling is the dominant factor leading to LISA in SES, both plaque reduction and vessel remodeling contributed to LISA in ZES.