'Heartburn' is a painful or burning sensation in the esophagus, just below the breastbone caused by regurgitation of gastric acid. The pain often rises in the chest and may radiate to the neck, throat, or angle of the jaw. Heartburn is also identified as one of the causes of chronic cough, and may even mimic asthma. Heartburn actually has nothing to do with the heart. It is so called because of a burning sensation of the breastbone where the heart is located although some heart problems do have a similar sensation to heartburn.