Heartburn, also known as acid indigestion, is a burning sensation in the central chest or upper central abdomen. The discomfort often rises in the chest and may radiate to the neck, throat, or angle of the jaw. Heartburn is usually due to regurgitation of gastric acid (gastric reflux) into the esophagus and is the major symptom of gastroesophageal reflux disease (GERD). In about 0.6% of cases it is a symptom of ischemic heart disease.
Eating spicy foods, such as pizza, may cause a person to feel heartburn. Although the name may imply the heart, heartburn has nothing to do with the heart itself. Heartburn is pain felt in the chest by a burning sensation in the esophagus, which is located close to where the heart is.
Here you can see the pizza passing from the mouth to the esophagus and on to the stomach. At junction between the stomach and esophagus is the lower esophageal sphincter. This muscular sphincter acts as a valve that normally keeps food and stomach acid in the stomach and prevents the stomach's contents from regurgitating back into the esophagus.
However, certain foods may affect the lower esophageal sphincter, making it less effective. That's how heartburn begins. The stomach produces hydrochloric acid to digest food. The stomach has a mucous lining that protects it from hydrochloric acid, but the esophagus does not.
So, when food and stomach acid regurgitate back into the esophagus, a burning feeling is felt near the heart. This feeling is known as heartburn. Antacids may be used to relieve heartburn by making stomach juices less acidic, therefore reducing the burning feeling felt in the esophagus. If heartburn becomes frequent or prolonged, medical intervention may be necessary to correct the problem.
The terms indigestion includes heartburn along with a number of other symptoms. Indigestion is sometimes 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.
Differential diagnosis
Heart attack symptoms and esophageal symptoms can be very similar, as the heart and esophagus use the same nerve supply.
Because of the dangers inherent in an overlooked diagnosis of heart attack, cardiac disease should be considered first in people with unexplained chest pain. People with chest pain related to GERD are difficult to distinguish from those with chest pain due to cardiac conditions. Each condition can mimic the signs and symptomatic findings of the other. Further medical investigation, such as imaging, is often necessary.
GERD Gastroesophageal reflux disease is the most common cause of heartburn. In this condition acid reflux has led to inflammation of the esophagus.
Functional heartburn is heartburn of unknown cause. It is associated with other functional gastrointestinal disorder like irritable bowel syndrome and is the primary cause of lack of improvement post treatment with proton pump inhibitors (PPIs). PPIs are however still the primary treatment with response rates in about 50% of people. The diagnosis is one of elimination, based upon the Rome III criteria: 1) burning retrosternal discomfort; 2) elimination of heart attack and GERD as the cause; and 3) no esophageal motility disorders.
Diagnostic approach:
Heartburn can be caused by several conditions and a preliminary diagnosis of GERD is based on additional signs and symptoms. The chest pain caused by GERD has a distinct 'burning' sensation, occurs after eating or at night, and worsens when a person lies down or bends over. It also is common in pregnant women, and may be triggered by consuming food in large quantities, or specific foods containing certain spices, high fat content, or high acid content. If the chest pain is suspected to be heartburn, patients may undergo an upper GI series to confirm the presence of acid reflux. Heartburn or chest pain after eating or drinking and combined with difficulty swallowing may indicate esophageal spasms.
Treatment
Antacids such as calcium carbonate are often taken to treat the immediate problem, with further treatments depending on the underlying cause. Medicines such as H2 receptor antagonists or proton pump inhibitors are effective for gastritis and GERD, the two most common causes of heartburn. Antibiotics are used if H. pylori is present.
Manometry: in this test, a pressure sensor (manometer) is passed via the mouth into the esophagus and measures the pressure of the lower esophageal sphincter directly.
Endoscopy: the esophageal mucosa can be visualized directly by passing a thin, lighted tube with a tiny camera known as an endoscope attached through the mouth to examine the esophagus and stomach. In this way, evidence of esophageal inflammation can be detected, and biopsies taken if necessary.
Biopsy: a small sample of tissue from the esophagus is removed. It is then studied to check for inflammation, cancer, or other problems.
