title: Impact of different stent alloys on human vascular response to everolimus-eluting stent: an optical coherence tomography study: the OCTEVEREST.
abstract: BACKGROUND
  New generation drug-eluting stents (DES) incorporate thinner struts and novel alloys to improve clinical performance. Nevertheless, the impact of novel stent materials and designs on human vascular response to DES remains elusive. We sought to evaluate the in-vivo coronary artery response to platinum-chromium (PtCr) versus cobalt-chromium (CoCr) stents featuring the same durable polymer and antiproliferative drug by optical coherence tomography (OCT).
  
  
  RESULTS
  A total of 42 patients with de novo lesions in native coronary vessels was treated with PtCr-everolimus eluting stent (EES; n = 21) or CoCr-EES (n = 21). Angiography, intravascular ultrasound, and OCT were performed at the index procedure and 6-month follow-up. PtCr-EES and CoCr-EES had similar concentric expansion (stent eccentricity index; median 0.91 vs. 0.90, respectively, P = 0.47) and very low rate of strut malapposition (median 1.15 vs. 1.80%, P = 0.92) at post implantation. Proportion of struts embedded in tissue was lower in PtCr-EES compared to CoCr-EES (median 2.67 vs. 15.23%, P < 0.001). The primary prespecified end point, the percentage of uncovered struts per patient at 6 months follow-up, was 8.46% [interquartile range (IQR) = 3.05-17.26] in PtCr-EES and 5.88% (IQR = 1.35-13.27) in CoCr-EES (P = 0.36), whereas malapposed struts were observed in 0.00% (IQR = 0.00-0.25) versus 0.48% (IQR = 0.00-1.44), respectively, (P = 0.10). Strut-level neointimal thickness did not differ between the two platforms (median 0.09 vs. 0.08 mm, P = 0.49).
  
  
  CONCLUSIONS
  Acute and mid-term responses to EES using PtCr or CoCr platforms were similar, with concentric stent expansion, low malapposition, similar strut coverage and limited amount of neointima. Conversely, at postprocedure, PtCr-EES had fewer embedded struts compared with CoCr-EES.
authors.affiliation: Cardiovascular Department, Ospedali Riuniti, Bergamo, Italy. guagliumig@gmail.com
authors.forename: Giulio
authors.initials: G
authors.lastname: Guagliumi
authors.forename: Davide
authors.initials: D
authors.lastname: Capodanno
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ikejima
authors.forename: Hiram G
authors.initials: HG
authors.lastname: Bezerra
authors.forename: Vasile
authors.initials: V
authors.lastname: Sirbu
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Musumeci
authors.forename: Luigi
authors.initials: L
authors.lastname: Fiocca
authors.forename: Nikoloz
authors.initials: N
authors.lastname: Lortkipanidze
authors.forename: Angelina
authors.initials: A
authors.lastname: Vassileva
authors.forename: Satoko
authors.initials: S
authors.lastname: Tahara
authors.forename: Orazio
authors.initials: O
authors.lastname: Valsecchi
authors.forename: Marco A
authors.initials: MA
authors.lastname: Costa
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000601:surgery; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D054855:Drug-Eluting Stents; D000068338:Everolimus; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization / Q000295:instrumentation*; D011446:Prospective Studies; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000494:pharmacology; D041623:Tomography, Optical Coherence / Q000379:methods*; D018084:Ultrasonography, Interventional
chemical_list: D000970:Antineoplastic Agents; D007166:Immunosuppressive Agents; D000068338:Everolimus; D020123:Sirolimus