Fulminant Myocarditis: Epidemiology, Pathogenesis, Diagnosis, and Management

Fulminant myocarditis (FM) is a rare, distinct form of myocarditis that has been difficult to classify. Since 1991, the definition of FM has evolved, and it is currently considered an acute illness with hemodynamic derangement and arrhythmias due to a severe inflammatory process requiring support of cardiac pump function and/or urgent management of serious arrhythmias. Diagnosis is aided through use of biomarkers and cardiac imaging, but endocardial biopsy remains the gold standard. Recent evidence has revealed that patients with FM are significantly more likely to die or require heart transplantation than those with the nonfulminant form, refuting previous studies proposing a paradoxically low mortality in patients with FM. Acute hemodynamic derangement is managed by intensive contemporary pharmacologic and interventional approaches, whereas the role of immunosuppressive therapy has not been clarified. Early recognition and aggressive management are essential for favorable outcomes. In conclusion, FM is an inflammatory process requiring intensive support, and it causes a higher morbidity and mortality than acute nonfulminant myocarditis.