**1. Introduction**

Demands for venoarterial extracorporeal membrane oxygenation (VA-ECMO) are growing worldwide to support the circulation in response to cardiogenic shock (CS) [1, 2]. One of the temporary mechanical circulatory support (tMCS) devices that are employed when there is circulatory failure is VA-ECMO [3]. Since its debut in 1972, VA-ECMO has been widely used to support clinicians in a variety of complex cardiac procedures on an emergency or preventative basis, including transcutaneous aortic valve implantation (TAVI) [4], complex percutaneous coronary intervention (PCI) [5], and postcardiotomy when it is difficult to wean the cardiopulmonary bypass (CBP) machine [6]. Considering ECMO is a more compact circuit than CPB and does not require cardiotomy suction or air-blood contact, it requires less anticoagulation, which could reduce coagulopathy and minimize systemic inflammation inflammatory response [4]. Refractory CS attributable to myocarditis, acute MI, acute cor pulmonale from a major pulmonary embolism, primary transplant graft failure, postcardiotomy CS, acute exacerbation of chronic heart failure, toxic ingestions, and intractable arrhythmias are only a few examples of specific indications for VA-ECMO (**Table 1**) [5].


*ECMO: extracorporeal membrane oxygenation; ECPR: extracorporeal cardiopulmonary resuscitation; SAVE: surviving after venoarterial ECMO trial; and VA: venoarterial.*

#### **Table 1.**

*Common indications and contraindications for using VA-ECMO.*

This chapter will focus on the indications related to the cardiac surgery, ECPR, periprocedural support, refractory CS secondary to AMI, postcardiotomy syndrome, and other high-risk procedures that require VA-ECMO.

### **2. ECMO for ischemic cardiogenic shock**

Despite the decline in the incidence of MI-related cardiogenic shock; myocardial infarction (MI) remains the top common cause of cardiogenic shock in more than 80% of cases [6]. Studies have shown that in the era of revascularization MI related cardiogenic shock is about 4 to 10 % [7, 8]. The largest of these studies, the SHOCK trial (Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock) recommended an early invasive approach to treat MI-related shock state to reduce mortality. However, mortality in such devastating complications remains high approaching 30% to 50% [7–9].

The challenge in CS and refractory cardiac arrest is always how to maintain systemic circulation, and ECMO could be appropriate in this situation. In the setting of persistently poor CS outcomes and technological advances in VA-ECMO, patients treated with cardiovascular MCS have exponentially increased over the last decade [10, 11].

### **3. Extracorporeal cardiopulmonary resuscitation**

Extracorporeal cardiopulmonary resuscitation (ECPR) refers to institution of VA-ECMO in the setting of stubborn cardiac arrest. The 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care stated that ECPR may be considered when spontaneous

circulation interrupting time is short, appropriate resuscitation efforts, and the cardiac arrest reason is possibly reversible or could be handled with revascularization or heart transplantation [12]. The guidelines emphasize that ECPR use should be limited to special centers that got the capabilities of running this complex intervention, in the view of managerial requirements of advanced equipment and highly trained personnel.
