title: Intravascular ultrasound findings after successful primary angioplasty for acute myocardial infarction: predictors of abrupt occlusion.
abstract: OBJECTIVE
  This study sought to evaluate the intravascular structure as depicted by intravascular ultrasound after successful primary angioplasty (i.e., without thrombolytic therapy) for acute myocardial infarction and to investigate the related predictors of acute coronary occlusion.
  
  
  BACKGROUND
  The usefulness of primary angioplasty for acute myocardial infarction is still limited by early reocclusion. There are few data regarding the intravascular ultrasound findings after primary angioplasty.
  
  
  METHODS
  Intravascular ultrasound was performed in 27 patients after successful primary angioplasty. Repeat coronary angiography was performed 15 min later, on the following day and 1 month after angioplasty.
  
  
  RESULTS
  Abrupt occlusion occurred in 8 of 27 patients. Angiographic variables in patients with versus those without abrupt occlusion were not significantly different. Intravascular ultrasound disclosed a significantly smaller lumen area ([mean +/- SD] 2.49 +/- 0.72 vs. 5.06 +/- 1.52 mm2, p < 0.001) and a significantly greater percent plaque area (80.5 +/- 9.1% vs. 63.7 +/- 7.8%, p < 0.001) in patients with abrupt occlusion. There was no significant difference in external elastic membrane cross-sectional area. We classified the ultrasound appearance of the intravascular structure as smooth, irregular or filled. Abrupt occlusion occurred in none of 6 patients with a smooth intravascular structure, 24% of 17 patients with an irregular structure and in all 4 with a filled structure (p < 0.05). In the latter group, the lumen was filled with bright speckled or low echogenic material, although angiography revealed excellent coronary dilation in all these arteries.
  
  
  CONCLUSIONS
  Intravascular ultrasound revealed a narrow lumen in coronary arteries showing abrupt occlusion after successful primary angioplasty, even though angiography disclosed successful dilation. Arteries with a lumen filled with bright speckled or low echogenic material frequently develop abrupt occlusion.
authors.affiliation: Division of Cardiology, Fukuyama Cardiovascular Hospital, Hiroshima, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Iwabuchi
authors.forename: S
authors.initials: S
authors.lastname: Haruta
authors.forename: A
authors.initials: A
authors.lastname: Taguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Ichikawa
authors.forename: T
authors.initials: T
authors.lastname: Genda
authors.forename: S
authors.initials: S
authors.lastname: Katai
authors.forename: T
authors.initials: T
authors.lastname: Imaoka
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: M
authors.initials: M
authors.lastname: Owa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000628:therapy*; D012008:Recurrence; D018084:Ultrasonography, Interventional