title: Prospective, Randomized, Multicenter Evaluation of a Polyethylene Terephthalate Micronet Mesh-Covered Stent (MGuard) in ST-Segment Elevation Myocardial Infarction: The MASTER Trial.
abstract: OBJECTIVE
  This study sought to evaluate the potential utility of a novel polyethylene terephthalate micronet mesh-covered stent (MGuard) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI).
  
  
  BACKGROUND
  Suboptimal myocardial reperfusion after PCI in STEMI is common and results in increased infarct size and mortality. The MGuard is a novel thin-strut metal stent with a polyethylene terephthalate micronet covering designed to trap and exclude thrombus and friable atheromatous debris to prevent distal embolization.
  
  
  METHODS
  A total of 433 patients with STEMI presenting within 12 h of symptom onset undergoing PCI were randomized at 50 sites in 9 countries to the MGuard (n = 217) or commercially available bare metal or drug-eluting stents (n = 216). The primary endpoint was the rate of complete (≥70%) ST-segment resolution measured 60 to 90 min post-procedure.
  
  
  RESULTS
  Baseline characteristics were well matched between the groups. The primary endpoint of post-procedure complete ST-segment resolution was significantly improved in patients randomized to the MGuard stent compared with control patients (57.8% vs. 44.7%; difference: 13.2%; 95% confidence interval: 3.1% to 23.3%; p = 0.008). By core laboratory analysis, the MGuard stent compared with control stents also resulted in superior rates of Thrombolysis In Myocardial Infarction 3 flow (91.7% vs. 82.9%, p = 0.006) with comparable rates of myocardial blush grade 2 or 3 (83.9% vs. 84.7%, p = 0.81). Mortality (0% vs. 1.9%, p = 0.06) and major adverse cardiac events (1.8% vs. 2.3%, p = 0.75) at 30 days were not significantly different between patients randomized to the MGuard stent and control stent, respectively.
  
  
  CONCLUSIONS
  Among patients with acute STEMI undergoing emergent PCI, the MGuard micronet mesh-covered stent compared with conventional metal stents resulted in superior rates of epicardial coronary flow and complete ST-segment resolution. A larger randomized trial is warranted to determine whether these benefits result in reduced infarct size and/or improved clinical outcomes. (Safety and Efficacy Study of MGuard Stent After a Heart Attack [MASTER]; NCT01368471).
authors.affiliation: Columbia University Medical Center and New York Presbyterian Hospital, New York, New York; Cardiovascular Research Foundation, New York, New York. gs2184@columbia.edu.
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
authors.forename: Alexandre
authors.initials: A
authors.lastname: Abizaid
authors.forename: Sigmund
authors.initials: S
authors.lastname: Silber
authors.forename: Jose M
authors.initials: JM
authors.lastname: Dizon
authors.forename: Béla
authors.initials: B
authors.lastname: Merkely
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Costa
authors.forename: Ran
authors.initials: R
authors.lastname: Kornowski
authors.forename: Andrea
authors.initials: A
authors.lastname: Abizaid
authors.forename: Roman
authors.initials: R
authors.lastname: Wojdyła
authors.forename: Akiko
authors.initials: A
authors.lastname: Maehara
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Dressler
authors.forename: Sorin J
authors.initials: SJ
authors.lastname: Brener
authors.forename: Eli
authors.initials: E
authors.lastname: Bar
authors.forename: Dariusz
authors.initials: D
authors.lastname: Dudek
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D003328:Coronary Thrombosis / Q000517:prevention & control; D054855:Drug-Eluting Stents; D057505:Embolic Protection Devices; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D062645:Percutaneous Coronary Intervention / Q000295:instrumentation*; D011093:Polyethylene Terephthalates; D011183:Postoperative Complications; D011446:Prospective Studies; D011474:Prosthesis Design; D016896:Treatment Outcome
chemical_list: D008670:Metals; D011093:Polyethylene Terephthalates