title: The effect of intra-aortic balloon counterpulsation on left ventricular functional recovery early after acute myocardial infarction: a randomized experimental magnetic resonance imaging study.
abstract: OBJECTIVE
  We sought to determine whether intra-aortic balloon pump (IABP) counterpulsation improves the recovery of left ventricular (LV) systolic function after reperfused acute myocardial infarction (AMI).
  
  
  RESULTS
  Fourteen dogs underwent 90-min coronary artery occlusion followed by reperfusion. Seven animals were randomized to IABP counterpulsation immediately after reperfusion. Tagged, cine, and contrast-enhanced magnetic resonance imaging were used for regional and global LV functional assessment and MI characterization, respectively. Image acquisition was performed at 1 h, 6 h, and 24 h after reperfusion, during which the IABP device was paused. Animals randomized to IABP demonstrated an earlier improvement of LV ejection fraction when compared with controls (25+/-3 vs. 25+/-2% at 1 h, P=0.91; 36+/-3 vs. 26+/-2% at 6 h, P=0.015; and 38+/-3 vs. 35+/-1% at 24 h, P=0.34). Regional functional analyses revealed the same behaviour among non-infarcted risk regions, i.e., earlier circumferential systolic strain improvement in the IABP group than in controls (-5.4+/-0.4 vs. -5.3+/-0.5% at 1 h, P=0.86; -12.1+/-1.0 vs. -6.0+/-0.4% at 6 h, P<0.001; and -13.9+/-1.1% vs. -12.8+/-0.6% at 24 h, P=0.40). Importantly, however, the degree of LV functional recovery 24 h after reperfusion was similar whether IABP counterpulsation was used or not.
  
  
  CONCLUSIONS
  IABP counterpulsation accelerates but does not significantly improve the recovery of LV systolic function after reperfused AMI.
authors.affiliation: Department of Medicine, Division of Cardiology, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287-0409, USA.
authors.forename: Clerio F
authors.initials: CF
authors.lastname: Azevedo
authors.forename: Luciano C
authors.initials: LC
authors.lastname: Amado
authors.forename: Dara L
authors.initials: DL
authors.lastname: Kraitchman
authors.forename: Bernhard L
authors.initials: BL
authors.lastname: Gerber
authors.forename: Thor
authors.initials: T
authors.lastname: Edvardsen
authors.forename: Nael F
authors.initials: NF
authors.lastname: Osman
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Rochitte
authors.forename: Katherine C
authors.initials: KC
authors.lastname: Wu
authors.forename: Joao A C
authors.initials: JA
authors.lastname: Lima
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004285:Dogs; D006339:Heart Rate / Q000502:physiology; D007423:Intra-Aortic Balloon Pumping; D018810:Magnetic Resonance Angiography / Q000379:methods; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008863:Microspheres; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D015425:Myocardial Reperfusion / Q000379:methods; D017682:Myocardial Stunning / Q000503:physiopathology / Q000628:therapy; D020127:Recovery of Function; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology / Q000628:therapy*