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Hiatal Hernia

Last Updated: December 29, 2004

Synonyms and related keywords: gastroesophageal reflux disease, GERD, gastric volvulus, hernias, hiatus hernia, paraesophageal hernias, paraesophageal hiatal hernia, Schatzki ring, phrenoesophageal ligament, esophagitis, Cameron ulcers, sliding hiatal hernia, regurgitation

Background: A hiatal hernia occurs when a portion of the stomach prolapses through the diaphragmatic esophageal hiatus. Although the existence of hiatal hernia has been described in earlier medical literature, it has come under scrutiny only in the last century or so because of its association with gastroesophageal reflux disease (GERD) and its complications. By far, most hiatal hernias are asymptomatic and are discovered incidentally. On rare occasion, a life-threatening complication, such as gastric volvulus or strangulation, may present acutely.

Pathophysiology: The esophagus passes through the diaphragmatic hiatus in the crural part of the diaphragm to reach the stomach. The diaphragmatic hiatus itself is approximately 2 cm in length and chiefly consists of musculotendinous slips of the right and left diaphragmatic crura arising from either side of the spine and passing around the esophagus before inserting into the central tendon of the diaphragm. The size of the hiatus is not fixed, but narrows whenever intra-abdominal pressure rises, such as when lifting weights or coughing.

The lower esophageal sphincter (LES) is an area of smooth muscle approximately 2.5-4.5 cm in length. The upper part of the sphincter normally lies within the diaphragmatic hiatus, while the lower section normally is intra-abdominal. At this level, the visceral peritoneum and the phrenoesophageal ligament cover the esophagus. The phrenoesophageal ligament is a fibrous layer of connective tissue arising from the crura, and it maintains the LES within the abdominal cavity. The A-ring is an indentation sometimes seen on barium studies, and it marks the upper part of the LES. Just below this is a slightly dilated part of the esophagus, forming the vestibule. A second ring, the B-ring, may be seen just distal to the vestibule, and it approximates the Z-line or squamocolumnar junction. The presence of a B-ring confirms the diagnosis of a hiatal hernia. Occasionally, the B-ring also is called the Schatzki ring.

Any sudden increase in intra-abdominal pressure also acts on the portion of the LES below the diaphragm to increase the sphincter pressure. An acute angle, the angle of His, is formed between the cardia of the stomach and the distal esophagus and functions as a flap at the gastroesophageal junction and helps prevent reflux of gastric contents into the esophagus (see Image 1). The gastroesophageal junction acts as a barrier to prevent reflux of contents from the stomach into the esophagus by a combination of mechanisms forming the antireflux barrier. The components of this barrier include the diaphragmatic crura, the LES baseline pressure and intra-abdominal segment, and the angle of His.

Frequency:

• In the US: Hiatal hernias are more common in Western countries. The frequency of hiatus hernia increases with age, from 10% in patients younger than 40 years to 70% in patients older than 70 years.

• Internationally: Burkitt et al suggest that the Western, fiber-depleted diet leads to a state of chronic constipation and straining during bowel movement, which could explain the higher incidence of this condition in Western countries.

Mortality/Morbidity: Paraesophageal hernias generally tend to enlarge with time, and sometimes the entire stomach is found within the chest. The risk of these hernias becoming incarcerated, leading to strangulation or perforation, is approximately 5%. This complication is potentially lethal, and surgical intervention is necessary. Because of the high mortality associated with this condition, elective repair often is advised wherever a paraesophageal hernia is found.

Sex: Hiatal hernias are more common in women than in men. This might relate to the intra-abdominal forces exerted in pregnancy.

Age: Muscle weakening and loss of elasticity as people age is thought to predispose to hiatus hernia, based on the increasing prevalence in older people. With decreasing tissue elasticity, the gastric cardia may not return to its normal position below the diaphragmatic hiatus following a normal swallow. Loss of muscle tone around the diaphragmatic opening also may make it more patulous.

History: Hiatal hernias are relatively common and, in themselves, do not cause symptoms. For this reason, most people with hiatal hernias are asymptomatic. Hiatal hernias may predispose to reflux or worsen existing reflux in a minority of individuals. Physicians should resist the temptation to label hiatal hernia as a disease.

Patients can have reflux without a demonstrable hiatal hernia. When a hernia is present in a patient with symptomatic GERD, the hernia may worsen symptoms for several reasons, including the hiatal hernia acting as a fluid trap for gastric reflux and increasing the acid contact time in the esophagus. In addition, with a hiatal hernia, episodes of transient relaxation of the LES are more frequent and the length of the high-pressure zone is reduced. The main symptoms of a sliding hiatal hernia are those associated with reflux and its complications.

No clear correlation exists between the size of a hiatal hernia and the severity of the symptoms. A very large hiatal hernia may be present with no symptoms at all. Some complications are specific for a hiatal hernia.

• Esophageal complications

• By far, the majority of hiatal hernias are asymptomatic.

• Often, patients are left with the impression that they have a disease when a hiatal hernia is diagnosed.

• In rare cases, however, a hiatal hernia may be responsible for intermittent bleeding from associated esophagitis, erosions (Cameron ulcers), or a discrete esophageal ulcer, leading to iron-deficiency anemia. This particular complication is more likely in patients who are bed-bound or those who take nonsteroidal anti-inflammatory drugs. Massive bleeding is rare.

• Nonesophageal complications

• Incarceration of a hiatal hernia is rare and is observed only with paraesophageal hernia.

• When this occurs, it can present abruptly, with a sudden onset of vomiting and pain, sometimes requiring immediate operative intervention.

Physical: The physical examination usually is unhelpful. Certain conditions predispose to the development of hiatus hernia. These include obesity, pregnancy, and ascites.

Causes:

• Predisposing factors include the following:

• Muscle weakening and loss of elasticity as people age is thought to predispose to hiatus hernia, based on the increasing prevalence in older people. With decreasing tissue elasticity, the gastric cardia may not return to its normal position below the diaphragmatic hiatus following a normal swallow. Loss of muscle tone around the diaphragmatic opening also may make it more patulous.

• Hiatal hernias are more common in women. This may relate to the intra-abdominal forces exerted in pregnancy.

• Burkitt et al suggest that the Western, fiber-depleted diet leads to a state of chronic constipation and straining during bowel movement, which might explain the higher incidence of this condition in Western countries.

• Obesity predisposes to hiatus hernia because of increased abdominal pressure.

• Conditions such as chronic esophagitis may cause shortening of the esophagus by causing fibrosis of the longitudinal muscles and, therefore, predispose to hiatal hernia. However, which comes first, the hiatal hernia worsening the reflux or the reflux-induced shortening of the esophagus, remains unknown.

• The presence of abdominal ascites also is associated with hiatal hernias.

• Diaphragmatic hernias may be congenital or acquired. Acquired hiatal hernias are divided further into nontraumatic and traumatic hernias. The most common types of hernias are those acquired in a nontraumatic fashion. Hernias acquired in a nontraumatic fashion are divided into 2 types, (1) sliding hiatal hernia and (2) paraesophageal hiatal hernia. A mixed variety with coexisting sliding and paraesophageal components is possible.

• Sliding hiatal hernia by far is the most common type of hiatal hernia. It occurs when the gastroesophageal junction, along with a portion of the stomach, migrates into the mediastinum through the esophageal hiatus (see Image 1). The majority of patients with demonstrated hiatal hernias are asymptomatic. This type of hernia interferes with the reflux barrier mechanism in several ways. As the LES moves into the chest, it no longer is exposed to positive intra-abdominal pressure and, therefore, is less effective as a sphincter. In fact, the sphincter moves into an area of low pressure, which interferes with the sphincter activity. In addition, the widening hiatus affects the competence of the diaphragmatic crura. The angle of His is lost, making regurgitation of gastric contents more likely. These changes not only predispose to reflux of gastric contents into the esophagus, but also prolong the acid contact time with the epithelium of the esophagus.

• In paraesophageal hernia, also called rolling-type hiatal hernia, the widened hiatus permits the fundus of the stomach to protrude into the chest, anterior and lateral to the body of the esophagus; however, the gastroesophageal junction remains below the diaphragm (see figure 3 of Image 1). This causes the stomach to rotate in a counter-clockwise direction. As the hiatus widens, increasing amounts of the greater curvature of the stomach and, sometimes, the gastric-colic omentum, follow. The fundus eventually comes to lie above the gastroesophageal junction, with the pylorus being pulled towards the diaphragmatic hiatus. In this type of hernia, the anatomic relation of the stomach to the lower end of the esophagus (angle of His) tends to remain unchanged, so gross acid reflux does not occur.

Other Problems to be Considered:

A mass lesion in the central chest could be confused with a hiatal hernia.

Lab Studies:

• The typical reasons for evaluation are symptoms of GERD or a chest radiograph suggesting a paraesophageal hernia.

Imaging Studies:

• Barium upper gastrointestinal series

• Although a chest radiograph may reveal a large hiatal hernia (see Image 2), and many incidentally diagnosed hiatal hernias are discovered in this manner, a barium study of the esophagus helps establish the diagnosis with greater accuracy (see Image 3).

• Typical findings include an outpouching of barium at the lower end of the esophagus, a wide hiatus through which gastric folds are seen in continuum with those in the stomach, and, occasionally, free reflux of barium.

• A barium study helps distinguish a sliding from a paraesophageal hernia (see Images 4-6). In rare cases, the entire stomach may herniate into the chest (see Image 7). The stomach may then undergo volvulus (see Image 8) and subsequent incarceration and strangulation.

Procedures:

• Endoscopy

• Hiatal hernia is diagnosed easily using upper gastrointestinal endoscopy.

• The diagnosis of a hiatal hernia actually is incidental, and endoscopy is used to diagnose complications such as erosive esophagitis, ulcers in the hiatal hernia, Barrett esophagus, or tumor.

• A hiatal hernia is confirmed when the endoscope is about to enter the stomach or on retrograde view once inside the stomach (see Image 9). If any doubt remains, the patient may be asked to sniff through the nose, which causes the diaphragmatic crura to approximate, seen as a pinch, closing the lumen.

• Endoscopy also permits biopsy of any abnormal or suspicious area.

Medical Care: When hiatal hernias are symptomatic, acid reflux usually produces the symptoms. If the hernia itself is causing chest discomfort or other symptoms, surgery may be necessary.

• When symptoms are due to GERD, the goals of treatment include prevention of reflux of gastric contents, improved esophageal clearance, and reduction in acid production. This is achieved in the majority of patients by a combination of the following:

• Modifying lifestyle factors

• Neutralizing acid or inhibiting acid production

• Enhancing esophageal and gastric motility

• The treatment of GERD is beyond the scope of this article and is discussed in Gastroesophageal Reflux Disease.

Surgical Care: A patient with a large hiatal hernia may experience vague intermittent chest discomfort or pain. The paraesophageal hernia may strangulate and frequently is operated on prophylactically to prevent this complication.

Surgery is necessary only in the minority of patients with complications of GERD despite aggressive treatment with proton pump inhibitors (PPIs). Because only a minority of patients with hiatal hernia have any problems, this represents a very small proportion of patients with sliding hiatal hernia; most patients with problems are managed medically.

By far, the majority of patients who would have undergone surgery in the past are managed successfully today with PPIs. However, young patients with severe or recurrent complications of GERD, such as strictures, ulcers, and bleeding, who cannot afford lifelong PPI treatment or would prefer to avoid taking medications long term, may be surgical candidates.

Another group of patients who are surgical candidates are those with pulmonary complications, in particular, asthma, recurrent aspiration pneumonia, chronic cough, or hoarseness linked to reflux disease.

Three major types of surgical procedures correct gastroesophageal reflux and repair the hernia in the process. They can be performed by open laparotomy or with laparoscopic approaches, which currently are being employed more frequently.

• Nissen fundoplication

• The Nissen fundoplication performed laparoscopically has gained popularity because of its lower morbidity and shorter hospital stay compared to the open procedure performed previously. Although a relatively high incidence of postoperative complications, such as dysphagia and gas bloating, are reported, DeMeester and Peters have shown that placing a larger bougie in the esophagus during this procedure, along with a shorter wrap and more complete mobilization of the stomach, have markedly reduced postoperative complications.

• This procedure involves a 360° fundic wrap around the gastroesophageal junction. The diaphragmatic hiatus also is repaired.

• A transthoracic approach may be used in patients who have had a previous Nissen wrap or those who have an irreducible hernia.

• The Toupet procedure is a variant of the Nissen wrap and involves a 180° wrap in an attempt to lessen the likelihood of postoperative dysphagia.

• Belsey (mark IV) fundoplication: This operation involves a 270° wrap in an attempt to reduce the incidence of gas bloating and postoperative dysphagia. It also is preferred when minimal esophageal dysmotility is suspected. To complete this operation, the left and right crura of the diaphragm are approximated.

• Hill repair: In this procedure, the cardia of the stomach is anchored to the posterior abdominal areas, such as the medial arcuate ligament. This also has the effect of augmenting the angle of His and thus strengthening the antireflux mechanism.

• The antireflux procedures discussed above offer relief of symptoms in 80-90% of patients. In most cases, the procedure of choice is the one with which the surgeon is most familiar. These procedures carry low mortality and morbidity rates, lower than 15-20%. DeMeester et al found the Nissen procedure superior to the Belsey and Hill repairs with regard to symptom relief and prevention of reflux postoperatively (as judged by pH monitoring). Good long-term results have been reported for antireflux surgery, with adequate control of reflux in the range of 80% at 10 years.

• Most patients with a paraesophageal hernia remain asymptomatic. In this type of hernia, symptoms from acid reflux usually do not occur. Instead, the most common symptom is epigastric or substernal pain. Some patients complain of substernal fullness, nausea, and dysphagia.

• A significant proportion of patients with this type of hernia develop incarceration of the hernia and possible gastric volvulus, which can lead to perforation.

• If perforation occurs, the mortality rate is high. Because of this, many surgeons advise elective repair when the diagnosis is made.

• The goal of surgery is to remove the hernia sac and close the abnormally wide esophageal hiatus.

• Some surgeons then tack the stomach down in the abdomen to prevent it from migrating upwards again, or, they perform a temporary gastrostomy to help decompress the stomach and anchor it in place in the abdominal cavity.

Diet:

• An appropriate diet maintains an ideal body mass index. Obesity predisposes to reflux disease.

• Burkitt et al suggest that the Western, fiber-depleted diet leads to a state of chronic constipation and straining during bowel movement, which would explain the higher incidence of this condition in Western countries.

Symptomatic acid reflux can be treated medically, either by neutralizing acid with antacids or blocking acid secretion with H2-receptor blocking drugs or the more potent PPIs. The treatment of GERD is discussed in Gastroesophageal Reflux Disease. Hiatal hernias, per se, only require attention if they are causing symptoms because of their size or if the patient is at risk of strangulation, in which case surgery may be indicated.

Patient Education:

• Raise awareness of the potential for complications of each type of hernia.

• Complications of the hernia itself: Paraesophageal hernia may strangulate.

• Complications from reflux disease: Heartburn, strictures, Barrett esophagus, and esophageal cancer may occur in a minority of patients with hiatal hernias.

• Instruct patients to seek medical attention if new symptoms develop or if GERD symptoms are poorly controlled.

• For excellent patient education resources, visit eMedicine's Esophagus, Stomach, and Intestine Center. Also, see eMedicine's patient education article Hiatal Hernia.

Medical/Legal Pitfalls:

• Failure to recognize cardiac disease, chronic lung disease, Barrett esophagus, strictures, and asthma

• Failure to distinguish the more common and benign sliding hernia from the paraesophageal type

Caption: Picture 1. Hiatal Hernia: Figure 1 shows the normal relationship of the gastroesophageal junction, stomach, esophagus, and diaphragm. Figure 2 shows a sliding hiatal hernia where the stomach immediately below the gastroesophageal junction is seen to prolapse through the diaphragmatic hiatus into the chest. Figure 3 shows a paraesophageal hernia in which the cardia or fundus of the stomach prolapses through the diaphragmatic hiatus, leaving the gastroesophageal junction within the esophageal cavity. Picture Type: Image

Caption: Picture 2. Figures 4 and 5 are anteroposterior and lateral views on chest radiograph showing a large hiatal hernia. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 3. Barium study shows a sliding hiatal hernia: The gastric folds can be seen extending above the diaphragm. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 4. A paraesophageal hernia is seen on an upper gastrointestinal series. Note that the gastroesophageal junction remains below the diaphragm. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 5. Paraesophageal hernia is seen on barium upper gastrointestinal series. The mucosal folds are seen going up into the chest, next to the esophagus. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 6. Barium radiograph view of a large paraesophageal hernia. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 7. A large paraesophageal hernia in which the entire stomach is seen in the chest cavity. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 8. Barium studies show gastric volvulus as the herniated stomach undergoes rotation. This situation requires surgical intervention. Courtesy of David Y. Graham, MD. Picture Type: X-RAY

Caption: Picture 9. A retrograde view of a hiatal hernia seen at endoscopy shows the gastric folds to the left of the scope shaft extending up into the hernia. Courtesy of David Y. Graham, MD. Picture Type: Photo