The incidence and clinical impact of stent strut fractures developed after drug-eluting stent implantation.

Background: Cases of stent strut fractures (SSFs) after DES implantation have been reported, but the clinical significance is uncertain. Then we sought to define the incidence and clinical implications of SSFs developed after drug-eluting stent (DES) implantation.
Methods: We gathered SSF cases from 13 centers in Korea retrospectively. SSF was defined as angiographically visible interrupted connection of stent struts or fewer visible stent struts at the suspected site than normally looking stented area on intravascular ultrasound (IVUS). Furthermore, we classified the SSFs cases into three patterns (disruption, avulsion, and displacement) according to the interruption site and absence or presence of displacement.
Results: Thirty-seven SSFs (2 disruption, 7 avulsion, 28 displacement) were detected in 35 lesions in 35 patients. All fractured stents were sirolimus-eluting stents (SESs). The incidence of SSFs was 0.84% and the proportion of restenosis related with SSF was 6.3% after SES implantation driven from the data of 8 centers. The average length of stent used was 49 mm, overlapping stenting was performed in 19 lesions (54%), and the average maximal angulation in the initial coronary angiography was 67 degrees . Twenty-four fractures (65%) were associated with focal in stent restenosis and 11 fractures (30%) with target lesion revascularization. No acute coronary syndrome developed.
Conclusions: SSF after DES implantation might be a considerable complication after DES implantation especially after SES implantation.