Effects of intra-aortic balloon pump counterpulsation on left ventricular mechanoenergetics in a porcine model of acute ischemic heart failure.
We investigated the effects of intra-aortic balloon pump (IABP) counterpulsation on left ventricular (LV) contractility, relaxation, and energy consumption and probed the underlying physiologic mechanisms in 12 farm pigs, using an ischemia-reperfusion model of acute heart failure. During both ischemia and reperfusion, IABP support unloaded the LV, decreased LV energy consumption (pressure-volume area, stroke work), and concurrently improved LV mechanical performance (ejection fraction, stroke volume, cardiac output). During reperfusion exclusively, IABP also improved LV relaxation (tau) and contractility (Emax, PRSW). The beneficial effects of IABP support on LV relaxation and contractility correlated with IABP-induced augmentation of coronary blood flow. In conclusion, we find that during both ischemia and reperfusion, IABP support optimizes LV energetic performance (decreases energy consumption and concurrently improves mechanical performance) by LV unloading. During reperfusion exclusively, IABP support also improves LV contractility and active relaxation, possibly due to a synergistic effect of unloading and augmentation of coronary blood flow.
3rd Department of Cardiology, Laiko Hospital, University of Athens School of Medicine, 67 Mikras Asias Street, 11 527, Athens, Greece, malliaras@gmail.com.
Konstantinos
K
Malliaras
Efstratios
E
Charitos
Nikolaos
N
Diakos
Iraklis
I
Pozios
Apostolos
A
Papalois
John
J
Terrovitis
John
J
Nanas
D000818:Animals; D003326:Coronary Circulation / Q000502:physiology; D006333:Heart Failure / Q000503:physiopathology*; D007423:Intra-Aortic Balloon Pumping; D017202:Myocardial Ischemia / Q000503:physiopathology* / Q000628:therapy; D013552:Swine; D016277:Ventricular Function, Left / Q000502:physiology*