Intravascular ultrasound assessment of optimal stent area to prevent in‐stent restenosis after zotarolimus‐, everolimus‐, and sirolimus‐eluting stent implantation

Abstract

Objectives and background The impact of underexpansion and minimal stent area (MSA) criteria in the second generation drug-eluting stents (DES) has not been addressed yet. Methods Using intravascular ultrasound (IVUS), we assessed the optimal cut-off values of post-stenting MSA to prevent in-stent restenosis (ISR). Poststenting IVUS data and 9-month follow-up angiography were available in 912 patients with 990 lesions: 541 sirolimus-eluting stents (SES), 220 zotarolimus-eluting stents (ZES) and 229 everolimus-eluting stents (EES). Results For the prediction of angiographic ISR, the MSA of each DES was measured. The poststenting MSA was 6.4 ± 1.8 mm² in SES, 6.2 ± 2.1 mm² in ZES and 6.2 ± 2.1 mm² in EES. At the 9-months follow-up, the incidence of angiographic ISR was similar between SES (3.3%) vs. ZES (4.5%) vs. EES. (4.4%), (P = 0.53). Multivariable logistic regression analysis identified the post-stenting MSA as the only independent predictor of angiographic ISR in ZES (Odds ratio 0.722, 95% confidence interval 0.581–0.897, P = 0.001) and in EES (Odds ratio 0.595, 95% confidence interval 0.392–0.904, P = 0.015). The best MSA cut-off value was 5.5 mm² for the prediction of SES restenosis (sensitivity 72.2% and specificity 66.3%). For ZES, the optimal MSA predicting ISR was 5.3 mm² (sensitivity 56.7% and specificity 61.8%). For EES, the MSA 2 predicted ISR (sensitivity 60.0% and specificity 60.0%). Conclusions As a preventable mechanism of ISR, smaller stent area predicted angiographic restenosis of the second generation DES as well as the first generation. The optimal cut-off values of post-stenting MSA for preventing restenosis were similar between ZES vs. EES vs. SES.