title: Clinical implications of distal embolization during coronary interventional procedures in patients with acute myocardial infarction: quantitative study with Doppler guidewire.
abstract: OBJECTIVE
  This study sought to investigate the timing and amount of embolic particles generation during the percutaneous coronary intervention (PCI) procedure and studied the relationship between embolic burden and coronary blood flow and myocardial damage.
  
  
  BACKGROUND
  Distal embolization is a major complication of PCI. The Doppler guidewire (DGW) can detect the embolic particles as high-intensity transient signals (HITS) during the PCI procedure.
  
  
  METHODS
  We prospectively studied 37 patients with acute myocardial infarction (MI). Under monitoring with the DGW, we performed first and second balloon angioplasty, followed by stenting and post-high-pressure dilatation. Left ventricular ejection fraction (LVEF) (%) and regional wall motion (RWM) (standard deviation/chord) were measured on days 1 and 22.
  
  
  RESULTS
  The HITS were detected in 35 of 37 patients. The number of HITS was the greatest after stenting (16 +/- 18) followed by first balloon inflation (5 +/- 4). There was a significant correlation between the total number of HITS and the corrected Thrombolysis In Myocardial Infarction frame count (r = 0.52, p = 0.003) and a significant weak inverse correlation between the total number of HITS and changes in LVEF and RWM (r = 0.37, p = 0.03 and r = 0.35, p = 0.04, respectively).
  
  
  CONCLUSIONS
  Distal embolization is common during PCI in patients with acute MI, and the majority of HITS were observed after stenting. An increase in the total number of HITS is associated with reduced coronary blood flow, and is weakly associated with poor recovery of left ventricular function.
authors.affiliation: Division of Cardiology, Sakurabashi Watanabe Hospital, Kita-ku, Osaka, Japan.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Okamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.forename: Katsuomi
authors.initials: K
authors.lastname: Iwakura
authors.forename: Toshiya
authors.initials: T
authors.lastname: Kurotobi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Koyama
authors.forename: Motoo
authors.initials: M
authors.lastname: Date
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Higuchi
authors.forename: Koichi
authors.initials: K
authors.lastname: Inoue
authors.forename: Kenshi
authors.initials: K
authors.lastname: Fujii
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000295:instrumentation; D001783:Blood Flow Velocity; D017023:Coronary Angiography; D003326:Coronary Circulation; D015150:Echocardiography, Doppler / Q000295:instrumentation*; D004617:Embolism / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020127:Recovery of Function; D015607:Stents; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000295:instrumentation*; D016277:Ventricular Function, Left