Left ventricular physiological effects of veno-arterial ECMO support during cardiogenic shock

Project Summary/Abstract Cardiogenic shock is a devastating problem that has had a relatively stagnant in-hospital mortality around 30-40% in the last decade. Consequently, an array of mechanical support strategies has emerged to mitigate the multi-organ hypoperfusion. Among them, percutaneous veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used to treat cardiogenic shock due to its capacity to be instituted rapidly in the cardiac catheterization laboratory and provide large volume complete hemodynamic and respiratory support. However, this strategy has notable disadvantages, namely high cost associated with its programmatic development and the potential for introducing iatrogenic complications in a very sick population. Prior invasive hemodynamic data from animal models have suggested that there is deterioration of LV performance due to increased stroke work within minutes of the commencement of VA-ECMO hemodynamic support. There is also observational clinical data showing that LV distension may worsen with VA-ECMO support. Conversely, human data from our group’s prior experience have suggested that VA-ECMO support in patients with minimal pulsatility after out-of-hospital cardiac arrest can dramatically improve cardiac recovery and rates of neurologically favorable survival. These conflicting data have led to the emergence of diverse management strategies including VA-ECMO in patients with cardiogenic shock either due to AMI or cardiac arrest. In the context of the rapidly increasing usage of VA-ECMO usage there is a critical need to identify the manner in which VA-ECMO affects cardiac hemodynamics in the setting of cardiogenic shock. To that goal we will pursue the following specific aims: 1. Define the LV pressure volume area (PVA) and stroke work at different levels of VA-ECMO support in patients cannulated for CS. 2. Define the temporal changes of LV stroke work with prolonged VA-ECMO support over the course of the hospitalization. The temporal recovery patterns will be associated with clinical hard endpoints of decannulation or transition to permanent cardiac assist devices/transplant or death. 3.Validate the accuracy of non-invasive reconstruction of PV-loops compared to invasively collected data to help establish an easier way to assess LV stroke work for every day practice. The expected outcome of this research proposal is to define the physiologic effect of VA-ECMO support on the left ventricle energetics and provide objective scientific clinical proof derived from a high mortality and morbidity patient population. Additionally, we expect that our data will be useful to establish normative hemodynamic and imaging principles and strategies for assessing patients on VA-ECMO.