Hisashi Umeda, Tomoko Kawai, Naoki Misumida, Tomoyuki Ota, Kazutaka Hayashi, Mitsunori Iwase, Hideo Izawa, Shigeo Sugino, Takeshi Shimizu, Yasushi Takeichi, Ryoji Ishiki, Haruo Inagaki, Yukio Ozaki, Toyoaki Murohara
CIRCULATION-CARDIOVASCULAR INTERVENTIONS, 4(4) 349-354, Aug, 2011
Background-Although stent fracture (SF) after sirolimus-eluting stent (SES) implantation has been recognized as one of the predisposing factors of in-stent restenosis, it remains uncertain whether SF can increase the risk of major adverse cardiac events (MACE), especially beyond 1 year after SES implantation. The aim of this study was to assess the impact of SF relative to non-SF on 4-year clinical outcomes after treatment with SES of comparable unselected lesions.
Methods and Results-A total of 874 lesions in 793 patients undergoing SES implantation and subsequent angiography 6 to 9 months after index procedure were analyzed. At 6- to 9-month angiographic follow-up, SF was identified in 70 of 874 lesions (8.0%). In-stent late loss was significantly higher in SF lesions versus non-SF lesions (0.42 +/- 0.59 mm versus 0.13 +/- 0.49 mm, P < 0.001), resulting in a significantly higher in-stent restenosis rate (21.4% versus 4.1%, P < 0.001). At 4 years, SF versus non-SF was associated with a significantly higher MACE rate (23.2% versus 12.6%, P = 0.014), mainly driven by significantly higher target-lesion revascularization (18.8% versus 10.2%, P = 0.029) rate. Adverse effects of SF on clinical outcomes occurred mostly within the first year (17.4% versus 6.6%, P = 0.001), with similar MACE rate between 1 and 4 years (5.8% versus 5.9%, P = 0.611). No significant differences between SF versus non-SF patients were observed in the cumulative frequency of very late stent thrombosis (2.9% versus 1.4%, P = 0.281), death (0% versus 2.1%, P = 0.252), or myocardial infarction (5.8% versus 2.9%, P = 0.165).
Conclusions-SF of SES was associated with higher MACE rate up to 1 year, mainly driven by higher target-lesion revascularization, whereas no significant association was evident between years 1 and 4. (Circ Cardiovasc Interv. 2011;4:349-354.)