Systemic hemodynamic and cardiac biomechanics changes induced by peripheral ECLS in a total closed chest cardiogenic shock sheep model

Veno-arterial ExtraCorporeal Life Support (VA-ECLS) is proposed as an efficient device to treat refractory cardiogenic shock (CS). If VA-ECLS restores systemic hemodynamics and thus end-organ perfusion, its consequences on native failing myocardium remain more questionable. Besides an increase in left ventricular (LV) afterload induced by retrograde blood flow, an increase in LV preload, LV wall stress, myocardial working as well as a decrease in coronary blood flow have been reported. Most of these cardiac biomechanics changes have been identified as triggers of myocardial remodeling pathways in a myocardial infarction model. Test the hypothesis that VA-ECLS during CS restores systemic hemodynamics but also provokes significant changes in cardiac biomechanics, which could initiate cardiac remodeling processes. A CS sheep model induced by percutaneous intra-coronary alcohol infusion was instrumented to assess cardiac biomechanics (conductance and Swan-Ganz catheter) and systemic hemodynamics. After a one-hour period of stability, a VA-ECLS was implanted through femoral access and blood flow was increased from 25% to 100% of baseline cardiac output by 30 min. Data are mean ± SEM and one-way ANOVA was used to assess the effects of ECLS on different parameters (vs. CS state). CS was characterized by a significant decrease in mean arterial pressure (−32 ±3%), cardiac index (−44 ±4%), and an increase in LVEDP (+86 ±24%). ECLS induced a significant and flow-dependent increase in MAP, carotid blood flow, and venous oxygen saturation. ECLS from 75% to 100% induced a significant decrease in central venous and mean pulmonary arterial pressures while a substantial increase in LV end-diastolic and end-systolic volumes, and arterial elastance was observed. Only ECLS 25 and 50% induced a significant decrease in pressure-volume area, stroke work, potential energy, and maximal elastance. At the high level of supply, all these parameters did not significantly differ from the CS state (Fig. 1). The ECLS restores systemic hemodynamics but also provokes significant changes in cardiac biomechanics. Whether such changes may be triggers of ventricular remodeling remains to be demonstrated by further experiments.