First clinical experience with a paclitaxel derivate-eluting polymer stent system implantation for in-stent restenosis - Immediate and long-term clinical and angiographic outcome

Background-It has been shown that antiproliferative drugs such as paclitaxel lower the amount of intimal hyperplasia after stent implantation, We report the first clinical experience of 7-hexanoyltaxol (QP2)-eluting polymer stent system (QuaDS) implantation for in-stent restenosis. Methods and Results-Fifteen consecutive patients with elective indication to percutaneous coronary intervention for in-stent restenosis were treated with the QuaDS-QP2 stent implantation. The QuaDS-QP2 stent was successfully implanted in all but 2 target lesions. In one lesion, the restenotic segment could not be completely covered by the stent, and in another lesion, a bare metal stent was implanted distally to the QuaDS-QP2 stent. One patient suffered from postprocedural non-Q-wave myocardial infarction (NQWMI). No other adverse events were observed during hospital stay. Six- and 12-month angiographic and clinical follow-up was scheduled for all patients. At 6 months, 3 patients had target lesion revascularization (20%). Two patients had restenosis (13.3%); one experienced restenosis in a gap between 2 drug-eluting stents, and the other had stent occlusion leading to NQWMI. Minimal intimal hyperplasia was observed in all the segments covered by drug-eluting stents (late loss=0.47 +/- 1.01 mm with a loss index =0.17 +/- 0.39). At 12 months, I patient suffered from NQWMI, and 8 of 13 patients (61.5%) had angiographic restenosis (late loss= 1.36 +/- 0.94 nun with a loss index=0.62 +/- 0.44). Conclusion-This first experience with QuaDS-QP2 stent implantation for in-stent restenosis revealed minimal intimal hyperplasia at the 6-month follow-up. However, the antiproliferative effect was not maintained at the 12-month follow-up, resulting in delayed occurrence of angiographic restenosis.