Myocarditis is an inflammatory disease of the myocardium with a broad spectrum of clinical presentations, ranging from mild symptoms to severe heart failure. The course of patients with myocarditis is heterogeneous, varying from partial or full clinical recovery in few days to advanced low cardiac output syndrome requiring mechanical circulatory support or heart transplantation. Fulminant myocarditis (FM) is a peculiar clinical condition and is an acute form of myocarditis, whose main characteristic is a rapidly progressive clinical course with the need for hemodynamic support. Despite the common medical belief of the past decades, recent comprehensive data, including a recent registry that compared FM with acute non-FM, highlighted that FM has a poor inhospital outcome, often requires advanced hemodynamic support, and may result in residual left ventricular dysfunction in survivors. This review aimed to provide an updated practical definition of FM, including essentials in the diagnosis and management of the disease. Finally, the outcome of FM was critically revised according to the current published registries focusing on the topic.