The relationship between re-endothelialization and endothelial function after DES implantation: comparison between paclitaxcel eluting stent and zotarolims eluting stent.

BACKGROUND: Several studies have reported re-endothelialization and endothelial function after drug-eluting stent (DES) implantation; however, the relationship between re-endothelialization and endothelial function after DES implantation has not been investigated yet. METHODS: A total of 14 patients underwent evaluation of re-endothelialization by optical coherence tomography (OCT) and endothelial function by incremental Ach infusion at 9 months after DES implantation (ZES: N = 7, PES: N = 7). The neointimal thickness (NIT) inside each strut, strut coverage, and malapposition at every 1 mm cross-section were evaluated by OCT and the endothelial function was estimated by measuring the coronary vaso-reactivity in response to acetylcholine (Ach) infusion into coronary arteries. RESULTS: Zotarolims eluting stent (ZES), compared with paclitaxcel eluting stent (PES), showed more homogeneous neointimal coverage of stent struts and low rate of malapposition. Vasoconstriction in response to Ach in the peri-stent region was also less pronounced in ZES than PES. In particular, vasoconstriction was more often observed in cases with inhomogeneous neointimal coverage of stent struts in the PES group. CONCLUSIONS: Our findings suggest that endothelial function seems to be better preserved with ZES than PES, and homogeneous neointimal coverage of stent struts seem to be associated with the preserved endothelial function.

Short- and long-term clinical impact of tissue protrusion after newer-generation drug-eluting stent implantation for acute coronary syndrome.

Although stent implantation may be associated with tissue protrusion (TP), especially in patients with acute coronary syndrome (ACS), its long-term clinical outcomes remain unknown. The aim of the current study was to evaluate the long-term clinical outcomes of ACS patients with TP after the implantation of newer-generation drug-eluting stents (DESs). We retrospectively evaluated 366 consecutive ACS patients who underwent primary percutaneous coronary intervention (PCI) with newer-generation DESs. All culprit lesions underwent pre- and post-PCI intravascular ultrasound (IVUS) examinations and were classified according to the presence or absence of post-stent TP. After primary PCI, 198 lesions (54.1%) displayed TP on IVUS examination. At the 12-month follow-up, the incidence of target lesion revascularization did not differ between patients with (n = 198) and without (n = 168) TP (3.5 vs. 4.2%, p = 0.790). The incidence of recurrent ACS (r-ACS) was higher in patients with versus those without TP (7.1 vs. 2.4%; log-rank test p = 0.043). Cox proportional hazard analysis showed that triple-vessel disease (HR = 9.258, p = 0.001), TP (HR = 3.149, p = 0.008), and low-density lipoprotein cholesterol reduction rate ≥ 50% (HR = 0.184, p = 0.008) were the independent predictors of r-ACS. TP detected using IVUS after DES implantation may be associated with the occurrence of r-ACS after the 12-month follow-up, although short-term clinical outcomes were not worse during the 12-month follow-up.