title: Strut coverage and late malapposition with paclitaxel-eluting stents compared with bare metal stents in acute myocardial infarction: optical coherence tomography substudy of the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) Trial.
abstract: BACKGROUND
  The safety of drug-eluting stents in ST-segment elevation myocardial infarction (STEMI) continues to be debated. Pathological studies have demonstrated an association between uncovered struts and subsequent stent thrombosis. Optical coherence tomography can detect stent strut coverage in vivo on a micron-scale level. We therefore used optical coherence tomography to examine strut coverage in patients with STEMI treated with paclitaxel-eluting stents (PES) and bare metal stents (BMS).
  
  
  RESULTS
  In the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, patients with STEMI were randomized 3:1 to PES or BMS implantation. In a formal substudy, optical coherence tomography at 13 months was performed in 118 consecutive randomized patients (89 PES, 29 BMS) in whom 188 stents were assessed (146 PES and 42 BMS). A total of 44 139 stent struts were analyzed by an independent core laboratory blinded to stent assignment. The primary prespecified end point, the percentage of uncovered stent struts per lesion at follow-up, was 1.1 ± 2.5% in BMS lesions versus 5.7 ± 7.0% in PES lesions (P < 0.0001). Malapposed struts were observed in 0.1 ± 0.2% of BMS lesions versus 0.9 ± 2.1% of PES lesions (P = 0.0003). Percentage net volume obstruction was 36.0 ± 15.4% with BMS and 19.2 ± 11.3% with PES (P < 0.0001).
  
  
  CONCLUSIONS
  In patients with STEMI undergoing primary percutaneous coronary intervention, implantation of PES as compared with BMS significantly reduces neointimal hyperplasia but results in higher rates of uncovered and malapposed stent struts as assessed by optical coherence tomography at 13-month follow-up. Further studies are required to determine the clinical significance of these findings.
  
  
  BACKGROUND
  URL: http://www.clinicaltrials.gov. Unique identifier: NCT00433966.
authors.affiliation: Division of Cardiology, Cardiovascular Department, Ospedali Riuniti di Bergamo, Bergamo, Italy. guagliumig@gmail.com
authors.forename: Giulio
authors.initials: G
authors.lastname: Guagliumi
authors.forename: Marco A
authors.initials: MA
authors.lastname: Costa
authors.forename: Vasile
authors.initials: V
authors.lastname: Sirbu
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Musumeci
authors.forename: Hiram G
authors.initials: HG
authors.lastname: Bezerra
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Suzuki
authors.forename: Aleksandre
authors.initials: A
authors.lastname: Matiashvili
authors.forename: Nikoloz
authors.initials: N
authors.lastname: Lortkipanidze
authors.forename: Laurian
authors.initials: L
authors.lastname: Mihalcsik
authors.forename: Antonio
authors.initials: A
authors.lastname: Trivisonno
authors.forename: Orazio
authors.initials: O
authors.lastname: Valsecchi
authors.forename: Gary S
authors.initials: GS
authors.lastname: Mintz
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Dressler
authors.forename: Helen
authors.initials: H
authors.lastname: Parise
authors.forename: Akiko
authors.initials: A
authors.lastname: Maehara
authors.forename: Ecaterina
authors.initials: E
authors.lastname: Cristea
authors.forename: Alexandra J
authors.initials: AJ
authors.lastname: Lansky
authors.forename: Roxana
authors.initials: R
authors.lastname: Mehran
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D003328:Coronary Thrombosis / Q000209:etiology / Q000473:pathology; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology / Q000628:therapy*; D058426:Neointima / Q000209:etiology* / Q000473:pathology; D017239:Paclitaxel / Q000008:administration & dosage*; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D050257:Tubulin Modulators / Q000008:administration & dosage
chemical_list: D008670:Metals; D050257:Tubulin Modulators; D017239:Paclitaxel