Differential relative efficacy between drug-eluting stents in patients with bare metal and drug-eluting stent restenosis; evidence in support of drug resistance: insights from the ISAR-DESIRE and ISAR-DESIRE 2 trials

摘要

Aims: In drug-eluting stent (DES) restenosis, the contribution of drug hyporesponsiveness is poorly defined. We sought to evaluate if, in the setting of treatment for in-stent restenosis, the relative efficacy of sirolimus-eluting stents (SES) and of paclitaxel-eluting stents (PES) depends on the underlying substrate in which the stents are implanted, i.e., on whether the restenosis occurs within bare metal stents or within SES. Methods and results: We pooled data from the ISAR-DESIRE and ISAR-DESIRE 2 randomised trials and analysed outcomes in SES-treated and PES-treated patients. In all, 650 patients were included. Angiographic follow-up was available for 87% of patients. In SES-treated patients, both late loss (LL) and percentage diameter stenosis (%DS) were lower in patients treated for bare metal stent restenosis compared with SES restenosis (0.21±0.59 mm versus 0.41±0.66 mm, p=0.007; 27.6±19.4% versus 34.0±20.9%, p=0.015, respectively). In PES-treated patients, LL and %DS were similar in patients treated for bare metal stent restenosis compared with SES restenosis (0.48±0.59 mm versus 0.39±0.71, p=0.47; 33.5±22.2% versus 32.7±18.6%, p=0.75, respectively). Similarly, in terms of overall clinical efficacy, in SES-treated patients clinical outcomes were better in patients with bare metal stent restenosis compared with SES restenosis while in PES-treated patients outcomes were similar in both groups. At multivariate analyses the use of SES to treat restenosis within SES was predictive of both higher LL and %DS. Conclusions: The efficacy of sirolimus-eluting but not paclitaxel-eluting stents is significantly reduced when used for treatment of SES restenosis as compared to bare metal stent restenosis. The lower antiresten-otic efficacy following SES implantation in patients with SES restenosis may support a role for drug resistance in restenosis within these stents.