Heartburn is due to reflux (backflow) of gastric acid and sometimes bile into the stomach. This can be temporary and of no significance if it is merely associated with overindulgence. If heartburn occurs regularly over time, however, it may indicate the presence of a serious medical condition called Gastro-esophageal Reflux Disease (GERD).
Patients with GERD have abnormal function of the esophageal sphincter, allowing acid from the stomach (and sometimes bile from the duodenum) to regurgitate back into the stomach, causing heartburn.
Complications of GERD are as follows:
1. Erosion of the lining of the distal esophagus that can lead to an ulcer with pain and bleeding
2. Scarring and narrowing of the esophagus, called esophageal stricture
3. Precancerous change involving the distal esophageal epithelium (Barrett’s Esophagus)
4. Esophageal cancer
The major medical concern in GERD is the effect of the acid over time on the lining cells of the distal esophagus. The cells are irritated and may undergo pre-cancerous change and, rarely, progress to esophageal cancer. Therefore, patients with severe GERD are monitored by upper GI Endoscopy (inserting a scope into the esophagus, stomach and duodenum) with biopsy of abnormal areas.
GERD is treated with antacids, stronger medications, elevation of the head of the bed, avoidance of food and drink before bedtime and, in severe cases, surgery.
Here are two organs other than the stomach that are affected by heartburn:
1. Esophagus: See above
2. Teeth and tissues in the mouth: During sleep, patients with severe reflux often end up with gastric fluids in the mouth. This can cause painful tongue and oral tissues in general, plus alteration of tooth enamel and ultimate dental decay.
The reference gives an excellent overall review of GERD including symptoms, causes, risk factors, complications, tests and treatment.