3. Heartburn / W.G. Thompson  

Pyrosis. 

Heartburn is a burning sensation experienced behind the sternum. It characteristically occurs or is worsened when the subject is bending over, straining or lying down, especially after a meal. It is aggravated by certain foods (acidic drinks, chocolate, coffee), obesity or anxiety. Unlike angina, it is not usually worsened by exercise or exertion. 

Heartburn may be associated with a sensation of reflux into the gullet, or even actual regurgitation into the mouth (with the risk of aspiration). It should be distinguished from rumination, in which the subject regurgitates meals routinely and then swallows them again, usually with no consequence beyond disgust in the observer. 

Heartburn is associated with reflux of gastric contents (usually acidic) into the esophagus. The mechanism is complex. Decreased tone or inappropriate relaxation of the lower esophageal sphincter favors reflux. Anatomic disturbances such as obesity or hiatus hernia may also be important. In diseases in which peristalsis of the esophagus is disturbed (e.g., scleroderma) any acid that does reflux into the esophagus will not be adequately cleared. 

Contrary to popular opinion, the presence of a hiatus hernia has a minor role in the genesis of heartburn (Figure 1). Both hiatus hernia and heartburn occur in approximately one-third of subjects (not necessarily the same third). Thus, individual cases may have heartburn without hiatus hernia and vice versa. 

The mechanism of the pain is obscure. There appear to be no nerve endings for pain in the esophageal mucosa. Severe esophagitis may exist in the absence of heartburn or indeed of any symptoms. Conversely, individuals with heartburn may have an apparently normal esophagus. This gives rise to the suspicion that gastroesophageal reflux may be associated with a disturbance in esophageal motility that is responsible for the sensation of heartburn. 

When heartburn is suspected, one should determine the effect of position, food, stress and exercise on the discomfort. The interviewer should carefully exclude such symptoms as dysphagia, odynophagia, weight loss, bleeding and anemia, which indicate complications of reflux or more serious esophageal disease. 

There are no physical findings that can be associated with heartburn. The presence of substernal or costochondral tenderness suggests a musculoskeletal origin for the symptom. 

The presence of heartburn implies that the individual has gastroesophageal reflux disease (GERD). If the burning retrosternal sensation is aggravated by bending and relieved by antacids, then no further investigation is necessary. Some, however, have a retrosternal sensation that cannot be distinguished from that of angina pectoris, particularly if it is in some way related to effort, relieved by nitroglycerin and associated with other features of heart disease. As discussed in the chapter on the esophagus, esophageal spasm may be responsible for chest pain. However, it is often difficult to prove this relationship even with sophisticated motility equipment. Musculoskeletal disturbances such as costochondritis may be responsible for chest pain; they are characterized by local tenderness. 
 

One-third of adults have experienced heartburn and one in ten suffer heartburn at least once per week. If the heartburn is not incapacitating and is unaccompanied by dysphagia or anemia, then a trial of therapy is a reasonable first approach. Foods that delay gastric emptying (e.g., fat) or that weaken the lower esophageal sphincter (e.g., chocolate, onions) should be avoided. Antacids or alginate compounds such as Gaviscon® are usually successful in relieving the symptoms or even preventing them. Having small meals, fasting before bedtime, elevating the head of the bed and avoiding bending or exertion on a full stomach may be beneficial as well. 

In the event that such simple management fails to relieve heartburn, or that dysphagia, anemia or bleeding occurs, then some investigation is necessary. An endoscopy provides the most information, since it allows the degree of inflammation of the esophagus to be assessed. This permits the physician to plan treatment on the basis of its security. Generally speaking, mild esophagitis may be successfully managed with an H₂ blocker, while severe (grade 3 or 4) esophagitis will require a proton-pump inhibitor. In either case, long-term treatment is usually required. If a stricture is present, it should be biopsied. If the stricture proves to be nonmalignant, dilation may be carried out. A more detailed discussion of pharmacologic therapy for gastroesophageal reflux disease is found in Chapter 5, "The Esophagus."