Cardiac sarcoidosis is an underdiagnosed disease that may be present in as many as 25% of patients with systemic sarcoidosis. Although most commonly recognized in patients with other manifestations of sarcoidosis, it may occur in isolation and its presence is often not appreciated. Cardiac sarcoidosis may present as asymptomatic left ventricular dysfunction, congestive heart failure, atrioventricular block, atrial or ventricular arrhythmia and sudden death. Although untested in clinical trials, early use of high-dose steroid therapy may halt or reverse cardiac damage. This article reviews the clinical manifestations, diagnosis and treatment of sarcoidosis, with an emphasis on new imaging techniques and therapies.