Intraprocedural stent thrombosis during implantation of sirolimus-eluting stents

BACKGROUND: Intraprocedural stent thrombosis (IPST) is a rare event (<0.01% in our experience with bare metal stents), with the exception of specific settings such as acute myocardial infarction, thrombus-containing lesions, and dissections. We report the occurrence of this event during elective implantation of sirolimus-eluting stents.METHODS AND RESULTS: Between April 2002 and August 2003, 670 patients with 1362 lesions were treated with Cypher (Cordis, Johnson and Johnson Co) sirolimus-eluting stent implantation in San Raffaele Hospital and EMO Centro Cuore Columbus. Diabetes mellitus was present in 142 patients (21%), and 164 (24.5%) had unstable angina. Pretreatment with glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors was carried out in 235 patients (35%). Total stent length per vessel was 42.9+/-28.3 mm. IPST occurred in 5 patients (0.7%). None of the patients with IPST were pretreated with GP IIb/IIIa inhibitors. Using univariate exact logistic regression, only total stent length per vessel, in millimeters (exact OR, 1.03; 95% CI, 1.011 to 1.046; P=0.0028), was associated with the occurrence of IPST.CONCLUSIONS: Stent length was associated with the occurrence of IPST. Particular attention will need to be directed to this potential complication when long sirolimus-eluting stents are being used.