Frequency of Stent Fracture as a Cause of Coronary Restenosis After Sirolimus-Eluting Stent Implantation

Stent fracture (SF) was suggested as a cause of restenosis after sirolimus-eluting stent (SES) implantation. This study was performed to evaluate the incidence and characteristics of SF to determine its contribution to restenosis in patients with in-stent restenosis (ISR) after SES implantation. From May 2003 to February 2006, SESs were used for percutaneous coronary intervention in 868 patients with 1,109 coronary narrowings. Follow-up coronary angiography was performed in 366 patients (42%), and 26 ISR lesions were observed. These patients were enrolled in this study. SF was divided into 3 types as avulsion, collapse, and partial based on the findings of fluoroscopy, coronary angiography, and intravascular ultrasound study. Of 26 patients with ISR lesions, SF was identified in 10. SF types were avulsion (5 patients), collapse (2 patients), and partial (3 patients). SF was identified at the midshaft (7 patients) and overlap sites (3 patients) of stents. SF was not observed in the 30 patients with ISR after bare-metal Bx Velocity stent implantation. Four patients with SF were treated with paclitaxel-eluting stents. In conclusion, SF is 1 of the leading causes of ISR after SES implantation. Careful fluoroscopic examination is necessary at the time of follow-up angiography to identify this problem.