Acute coronary syndrome is an independent risk factor for late incomplete stent apposition after sirolimus-eluting stent implantation

Background Late incomplete stent apposition （ISA） may occur after drug-eluting stent implantation, affecting long-term clinical outcomes. This study aimed to evaluate the impact of clinical presentations of coronary artery disease on late ISA after percutaneous coronary intervention （PCI） with sirolimus-eluting stents （SES） by means of three-dimensional volumetric intravascular ultrasound （IVUS） analyses. Methods One hundred and thirty-seven patients with coronary artery disease received SES implantation during PCI and had repeat angiography with IVUS examination. All patients were followed up one year after the procedure. Results In overall 219 treated lesions （137 patients）, late ISA was identified in 25 lesions （16 patients）. Clinical diagnosis of acute coronary syndrome （ACS） and use of long stents were more common in patients with than in those without late ISA. Patients with late ISA had greater external elastic membrane （EEM） area in stented segment （（15.34±5.44） vs （13.83±4.51） mm^2, P=0.026）, stented-to-reference segment EEM area ratio （1.13±0.22 vs 1.02±0.18, P 〈0.001）, and plaque and media area （（8.43±3.93） vs （7.01±2.93） mm^2, P =0.002） than in those without late ISA. Multivariate Logistic regression analysis showed that clinical diagnosis of ACS and use of long stents were independent risk factors for late ISA （OR 6.477, 95%CI 2.297-18.263, P 〈0.001; OR 3.680, 95%Cl 1.181-11.469, P =0.025; respectively）. During one-year follow-up after IVUS examination, the rate of very late stent thrombosis tended to be higher in patients with than in those without late ISA （18.7% vs 3.3%, P =0.051）. Conclusions The occurrence of late ISA after SES implantation may be related to clinical status, use of long stents, and marked positive vessel remodeling. Late ISA tended to increase the rate of very late stent thrombosis during follow-up, highlighting the importance of long-term dual antiplatelet therapy for these patients.

A more than 2-year follow-up of incomplete apposition after drug-eluting stent implantation

Background Incomplete stent apposition （ISA） has been demonstrated to be more common after drug-eluting stent （DES） implantation than after bare metal stent （BMS） implantation, Clinical outcomes of ISA remain controversial and the predictive accuracy of previous studies was limited by the short follow-up period of only 12-18 months. In the present study, we present the outcomes of a more than 2-year follow-up in patients with ISA after DES implantation, Methods From the clinical and core intravascular ultrasound （IVUS） database of the hospital, we identified 76 patients who had undergone DES implantation in de novo lesions between January 2004 and June 2005 and had received IVUS examination at a scheduled 6-month follow-up. A total of 13 （17.1%） patients had documented I SA at the follow-up by IVUS. Clinical follow-up was available up to 41 months after DES implantation and up to 33 months after identification of ISA, Results Over a mean follow-up of （34：~5） months （range 24-41 months）, 3 of the 13 patients （23.1%） suffered from ST elevated myocardial infarction with one death. Angiography confirmed the very late stent thrombosis （ST） in the area with ISA, All the 3 patients were implanted with sirolimus elulJng stents in left anterior descending artery （LAD） and the very late ST occurred at 29, 31 and 32 months after DES implantation, and separately at 20, 23 and 23 months after the identification of ISA, All of the 3 patients had antiplatelet therapy continued before suffering from ST, and had been apparentJy stable on antiplatelet monotherapy with aspirin for a long peried following dual antiplatelet therapy with aspirin and clopidogrel for more than 12 months. Conclusion ISA of DES may be associated with a high incidence of very late stent thrombosis, even in clinically stable patients with dual antiplatelet therapy of at least 12 months after the procedure.