The fundamentals of extra-corporeal membrane oxygenation

During the past 50 years, pharmacologic advancements for cardiovascular risk factors and device innovation for the management of coronary disease, including acute myocardial infarction have radically changed the landscape of heart disease. At present, nearly 25% of individuals develop chronic heart failure after an acute myocardial infarction. It is estimated that nearly 2.6% of the American population suffers from heart failure. In the modern era, miniaturized continuous flow ventricular assist devices are now demonstrating nearly 75% 2-year survival rates with improved patient functionality. As a result, elderly patients with cardiogenic shock for whom medical treatment held minimal promise, may now be viable candidates for advanced mechanical therapies. Given this option, there is a need for more approaches to salvage patients from cardiogenic shock with percutaneously delivered mechanical circulatory support (pMCS) systems. The use of pMCS is growing and now includes patients with acute and chronic heart failure as well as patients undergoing high risk interventional and electrophysiology procedures. Each of these devices has a unique hemodynamic effect and therefore an in-depth understanding of device characteristics is required for optimal patient management. Extracorporeal membrane oxygenation (ECMO) is one of the earliest types of pMCS systems primarily used for cardiorespiratory failure. ECMO can be used in different configurations, which makes it a versatile hemodynamic support device for different patient scenarios. In this paper, the authors review different configurations, indications, and hemodynamic profile of ECMO in respiratory and cardiac failure patients.