title: Comparison of myocardial perfusion by distal protection before and after primary stenting for acute myocardial infarction: angiographic and clinical results of a randomized controlled trial.
abstract: OBJECTIVE
  To assess the myocardium-reperfusing effect of a distal protection device, GuardWire Plus (GuardWire Plus), in patients with acute myocardial infarction (AMI).
  
  
  BACKGROUND
  Distal embolization may result in reduced myocardial perfusion, increasing the risk of non-Q-wave myocardial infarction and death. Distal protection devices may protect the microcirculation from embolic debris, improving short- and long-term clinical outcomes.
  
  
  METHODS
  From February 2002 to July 2003, a total of 341 AMI patients at 22 institutions in Japan were enrolled in the present, multicenter, prospective, randomized trial. Patients experiencing AMI within 12 hr of symptom onset, who were considered treatable by stenting and who met the inclusion criteria, were eligible for randomization. Stenting with and without GuardWire Plus was conducted to examine whether the device provides faster and more complete ST-segment resolution, smaller infarct size, and improved myocardial blush score.
  
  
  RESULTS
  The rates of slow flow and no-reflow immediately after PCI were 5.3 and 11.4% in the GuardWire Plus and control groups, respectively (P = 0.05). Blush score 3 acquisition rates immediately after PCI were 25.2 and 20.3% in the GuardWire Plus and control groups, respectively (P = 0.26), and the rates at 30 days after PCI were 42.9 and 30.4%, respectively (P = 0.035).
  
  
  CONCLUSIONS
  A significant difference was found between the GuardWire Plus and control groups with respect to the total incidence of distal embolization, indicating that GuardWire Plus angiographically improved myocardial perfusion without demonstrating the preventive effect of myocardial damage.
authors.affiliation: Saiseikai Yokohama-City Eastern Hospital, Kanagawa, Japan. t-mura@tj8.so-net.ne.jp
authors.forename: Toshiya
authors.initials: T
authors.lastname: Muramatsu
authors.forename: Ken
authors.initials: K
authors.lastname: Kozuma
authors.forename: Reiko
authors.initials: R
authors.lastname: Tsukahara
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Ito
authors.forename: Naoya
authors.initials: N
authors.lastname: Fujita
authors.forename: Satoru
authors.initials: S
authors.lastname: Suwa
authors.forename: Shiho
authors.initials: S
authors.lastname: Koyama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Saitoh
authors.forename: Haruo
authors.initials: H
authors.lastname: Kamiya
authors.forename: Masato
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D003326:Coronary Circulation; D004562:Electrocardiography; D004617:Embolism / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000628:therapy*; D015425:Myocardial Reperfusion; D011446:Prospective Studies; D012307:Risk Factors; D015607:Stents; D016896:Treatment Outcome