The Role of Extracorporeal Life Support in Acute Myocarditis: A Bridge to Recovery?

Myocarditis is an inflammatory process within the myocardium that produces life-threatening ventricular systolic dysfunction (1,2). Acute fulminant myocardial failure is associated with a rapid, profound decompensation in systolic function and severe heart failure, resulting in circulatory collapse (3). Despite the acute nature and profound sequelae, if myocarditis is quickly diagnosed and aggressively treated, greater than 90% will make a full recovery with minimal long-term complications (4). Patients diagnosed with acute, nonfulminant myocarditis experience a course characterized by a gradual progression to heart failure with subsequent development of chronic myocarditis. Patients progressively develop chronic, stable, dilated cardiomyopathy (4). Histologically, lymphocytic infiltration and myocardial cytolysis are common to myocarditis and likely account for the associated severe systolic dysfunction and refractory/intractable arrhythmias (1,5,6). Myocarditis is caused by a myriad of agents including infectious disease, autoimmune syndromes, or exposure to drugs, noxious compounds, or heavy metals (Table 2) (4). The majority of myocarditis cases are likely the result of virus-borne infection, primarily coxsackievirus, parvovirus, and adenovirus; however, a definitive diagnosis often proves difficult (7). Table 2. Potential causes of myocarditis. Patients generally present with flu-like symptoms, fever, and malaise days or weeks before an acute event (8). On physical examination, cardiogenic shock symptoms aremanifest, including tachycardia, hypotension, and hypoperfusion (9). After an acute exacerbation, the patient can demonstrate profoundly diminished ventricular function, malignant arrhythmias, circulatory collapse, indications of multiorgan failure, and can be quite difficult to manage. At this point, successful care is contingent on preserving end-organ function. Institution of early ECLS can support end organ function and reverse an unstable clinical situation. Relative to other mechanical support means, using ECLS for these patients is a safe and reliable therapy. ECLS support results in an immediate reduction in inotropic support, reduction of mechanical respiratory support, stabilization of end organ function, and reduced need for aggressive antidysrhythmic management or cardioversion. Modern ECLS technology has improved dramatically in the last 10 years. The blood/device interface has become more biopassive, and the technology has enjoyed renewed interest. However, ECLS is not a benign therapy. Significant morbidity can be associated with its use. Several authors have documented the use of ventricular assist devices (VADs) for support and have suggested only these devices effectively decompress the left ventricle and hence allow for myocardial remodeling and recovery (5–7,10–13). Concern remains regarding the ability of ECLS to effectively decompress the left ventricle in these patients and provide for myocardial recovery (12,13). A growing body of literature suggests some patients may experience myocardial recovery such that ECLS can actually represent a definitive therapy (14–17). With this in mind, we review our patient series treating acute decompensatory myocarditis using ECLS and the role of ECLS for myocardial recovery.