title: Role of collateral circulation in the acute phase of ST-segment-elevation myocardial infarction treated with primary coronary intervention.
abstract: OBJECTIVE
  The role of collateral flow in the first hours of infarction remains unclear. Our aim was to determine whether the presence of coronary collateral flow, as evidenced by angiography, has a beneficial effect on infarct size and left ventricular function in acute myocardial infarction (MI) treated by means of early percutaneous coronary intervention (PCI).
  
  
  METHODS
  Between 1994 and 2001, 1059 patients with acute MI treated with primary PCI, TIMI (Thrombolysis in Myocardial Infarction) 0 or 1 flow at first contrast injection and technically adequate angiograms for collateral flow detection were analysed.
  
  
  RESULTS
  Comparison of collateral flow grades 0, 1, and 2/3 showed that increased collateral flow was associated with a lower incidence of Killip class >/= 2 at presentation (12% vs. 10% vs. 3%, p for trend 0.02), less need for intra-aortic balloon pumping after PCI (17% vs. 13% vs. 5%, p for trend 0.005), better myocardial blush grade (MBG) in infarcts related with the left anterior descending coronary artery (LAD) (MBG3: 14% vs. 18% vs. 34%, p for trend 0.01), and smaller enzymatic infarct size (cumulative lactate dehydrogenase release 36 h after symptom onset [LDHQ(36)]) (1932+/-1531 U/l vs. 1870+/-1458 U/l vs. 1217+/-762 U/l, p for trend 0.041). These beneficial effects were particularly evident in LAD-related infarcts.
  
  
  CONCLUSIONS
  The presence of angiographically detectable collaterals has a protective effect on enzymatic infarct size and pre- and postintervention haemodynamic conditions in patients with acute MI treated by primary PCI, in particular when Rentrop grade 2/3 is present and the LAD is involved in the infarct.
authors.affiliation: Department of Cardiology, Isala Klinieken, Locatie Weezenlanden, Groot Wezenland 20, 8011 JW Zwolle, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Elsman
authors.forename: A W J
authors.initials: AW
authors.lastname: van 't Hof
authors.forename: M J
authors.initials: MJ
authors.lastname: de Boer
authors.forename: J C A
authors.initials: JC
authors.lastname: Hoorntje
authors.forename: H
authors.initials: H
authors.lastname: Suryapranata
authors.forename: J H E
authors.initials: JH
authors.lastname: Dambrink
authors.forename: F
authors.initials: F
authors.lastname: Zijlstra
mesh_terms: D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D001783:Blood Flow Velocity / Q000502:physiology; D003097:Collateral Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome