CONICET | Buscador de Institutos y Recursos Humanos

The effectiveness of intra-aortic balloon pumping(IABP) is currently evaluated using indirect indexes.The diastolic pressure augmentation is quantified usingthe subendocardial viability ratio (SEVR) and theDABAC/SABAC index (areas beneath the aortic pressure?time signals during the diastolic and systolic periods,respectively). The SEVR requires invasive recordings ofleft ventricular pressure; the DABAC/SABAC index mayrepresent an alternative, since it only requires an aorticpressure signal. Nonetheless, it has never been used in ananimal model of counterpulsated heart failure and ischemia-reperfusion episode. The aims of this work were:(i) to develop an animal model of heart failure, with amyocardial ischemia-reperfusion episode, treated withIABP during the reperfusion period; (ii) to evaluate theeffects of the IABP using the SEVR and DABAC/SABAC indices; and (iii) to assess the relationship betweenboth ratios. Cardiovascular parameters were obtainedin anesthetized sheep, in which induced heartfailure and ischemia-reperfusion episodes were monitoredwith and without IABP 1:2. Systolic and diastolicblood pressure signals were assessed in the aorta and inthe left ventricle. Values of cardiac output and left ventricularwall thickness signals were obtained. Induction ofischemia and heart failure determined decreases in SEVRand DABAC/SABAC indices with respect to their basalstage (0.807 ± 0.118 vs. 0.601 ± 0.107, P < 0.05 and1.062 ± 0.136 vs. 0.902 ± 0.161, P < 0.05, respectively).Counterpulsated animals whose myocardial reperfusionwas accompanied by heart failure showed a significant improvementof wall thickening fraction along time(R2 = 0.7627, P < 0.001). During counterpulsated heartfailure accompanied by myocardial reperfusion, theSEVR was positively correlated with DABAC/SABACindex.