The effect of intra-aortic balloon counterpulsation on left ventricular functional recovery early after acute myocardial infarction: a randomized experimental magnetic resonance imaging study.
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.
Azevedo
Clerio F
CF
Department of Medicine, Division of Cardiology, Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21287-0409, USA.
Amado
Luciano C
LC
Kraitchman
Dara L
DL
Gerber
Bernhard L
BL
Edvardsen
Thor
T
Osman
Nael F
NF
Rochitte
Carlos E
CE
Wu
Katherine C
KC
Lima
Joao A C
JA
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*