APA Dictionary of Psychology

an anxiety state identified in soldiers during the American Civil War (1861–1865) in which heart palpitations were the most prominent symptom. It is now recognized as a form of panic disorder observed in soldiers during the stress of combat and marked by fatigue, heart palpitations, chest pain, and breathing difficulty. See also combat stress reaction; effort syndrome. [Jacob Méndes Da Costa (1833–1900), U.S. surgeon]