title: Terminal QRS complex distortion on the admission electrocardiogram in anterior acute myocardial infarction and association with residual flow and infarct size after primary angioplasty.
abstract: BACKGROUND
  Terminal QRS complex distortion on admission is a simple and reliable predictor of infarct size in patients with acute myocardial infarction (AMI). It is uncertain, however, whether this reflects reduced myocardial perfusion of the infarct area and a larger area of the myocardium at risk. This study was conducted to investigate whether terminal QRS distortion complex on admission is a reliable predictor of reduced residual flow and a larger area of the myocardium at risk compared to patients who are admitted without a terminal QRS distortion.
  
  
  METHODS
  We evaluated the relationship between terminal QRS complex distortion and residual flow to the infarct zone and risk area in 46 anterior AMI patients undergoing primary angioplasty. (99m)Tc-sestamibi imaging was performed at baseline and 5-9 days after angioplasty. The study population was divided into those with (Group I, n=16) and without (Group II, n=30) terminal QRS complex distortion.
  
  
  RESULTS
  Baseline characteristics were similar between the two groups. The area of the myocardium at risk was higher in Group I (59.9 +/- 15.3%) than in Group 11 (48.6 +/- 13.7%, p < 0.05; mean+SD) while the nadir measurement of the residual flow was lower in Group I (0.10 +/- 0.07) than in Group 11 (0.16 +/- 0.09, p < 0.05). Although the final infarct size was significantly higher in Group I (40.8 +/- 17.2%) than in Group 11 (27.1 +/- 18.1%, p < 0.05), the myocardial salvage index did not differ significantly between the two groups.
  
  
  CONCLUSIONS
  Terminal QRS complex distortion seems to be associated with less residual flow to the infarct zone, a larger risk area and greater infarct size in patients with anterior AMI.
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Hyun Suk
authors.initials: HS
authors.lastname: Yang
authors.forename: Cheol Whan
authors.initials: CW
authors.lastname: Lee
authors.forename: Myeong-Ki
authors.initials: MK
authors.lastname: Hong
authors.forename: Dae-Hyuk
authors.initials: DH
authors.lastname: Moon
authors.forename: Young-Hak
authors.initials: YH
authors.lastname: Kim
authors.forename: Sang-Gon
authors.initials: SG
authors.lastname: Lee
authors.forename: Ki-Hoon
authors.initials: KH
authors.lastname: Han
authors.forename: Jae-Joong
authors.initials: JJ
authors.lastname: Kim
authors.forename: Seong-Wook
authors.initials: SW
authors.lastname: Park
authors.forename: Seung-Jung
authors.initials: SJ
authors.lastname: Park
mesh_terms: D000800:Angioplasty, Balloon; D003326:Coronary Circulation / Q000502:physiology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology* / Q000628:therapy*; D012039:Regional Blood Flow / Q000502:physiology