Heartburn, also known as pyrosis, cardialgia, or acid indigestion is a burning sensation in the chest, just behind the breastbone or in the epigastrium. The pain often rises in the chest and may radiate to the neck, throat, or angle of the jaw. Heartburn is usually associated with regurgitation of gastric acid (gastric reflux) which is the major symptom of gastroesophageal reflux disease (GERD). It however may also be a symptom of ischemic heart disease, though this is true for only 0.6% of those experiencing heartburn. The terms dyspepsia and indigestion are often used interchangeably with heartburn, though some sources emphasize a distinction. Dyspepsia is defined as a combination of epigastric pain and heartburn. Heartburn is commonly used interchangeably with gastroesophageal reflux disease rather than just to describe a symptom of burning in one's chest. Cardiac and esophageal causes may share similar symptoms as these two structures have the same nerve supply. Cardiac disease is one of the first conditions that must be excluded in patients with unexplained chest pain given that patients with chest pain related to GERD cannot be distinguished from those with chest pain due to
Contributions by Ichibani, Lee J Haywood, and Hu12.