Infections of the heart can be acute or subacute, depending on host susceptibility, the cause and associated virulence, early diagnosis, and effective therapy. The following review will discuss the causes, clinical manifestations, diagnosis, and medical or surgical management of infective endocarditis, prosthetic valve endocarditis, myocarditis, and pericarditis. Nursing considerations emphasize understanding the pathogenesis, early recognition of signs and symptoms, and appropriate prevention and intervention.