Hiatal Hernia

Definition

Hiatal hernias are defined as herniation of the stomach into the chest, as the stomach pushes up from the abdomen into the chest cavity. Herniation occurs through the diaphragmatic esophageal hiatus, which is an opening in the diaphragm through which the esophagus connects to the stomach.

There are four types of hiatal hernia:

• Type I hiatal hernia
• Type II (paraesophageal) hiatal hernia
• Type III hiatal hernia
• Type IV hiatal hernia

Type I hiatal hernia:  

Type I hiatal hernia is the most common type. It is also called a sliding hiatal hernia. This type accounts for about 95 percent of all hiatal hernias. In this type of hernia, the gastroesophageal junction is herniated into the chest cavity, as shown in the image below.

Type II (paraesophageal) hiatal hernia:

Type II hiatal hernia is also called a paraesophageal hiatal hernia, in which the stomach herniates through the diaphragmatic esophageal hiatus alongside the esophagus. In the type II or "pure" paraesophageal hernia, the gastroesophageal junction remains below the hiatus and the stomach rotates in front of the esophagus and herniates into the chest (see image below). If more than 30 percent of the stomach herniates into the chest, the condition is also called a giant paraesophageal hernia.

"Pure" type II paraesophageal hernia seldom occurs. Paraesophageal hiatal hernias make up less than 5 percent of all hiatal hernias, but account for most of the hiatal hernia complications.

Type III hiatal hernia:

Type III hiatal hernias are combined hernias in which the gastroesophageal junction is herniated above the diaphragm and the stomach is herniated alongside the esophagus. The majority of paraesophageal hernias are type III (see image below).

Type IV hiatal hernia:

In type IV hiatal hernias, other organs in addition to the stomach (colon, small intestine, spleen) also herniate into the chest (see image below).

Causes

The exact cause of hiatal hernias is unknown. They are mostly caused by weakening of the muscles of the diaphragm around the esophagus. Other causes that increase the intra-abdominal pressure such as pregnancy will contribute to formation of hiatal hernias.

Symptoms

Small sliding hiatal hernias (Type I hiatal hernia) can be asymptomatic (not causing any problem). The most common symptoms associated with symptomatic hiatal hernias are the following:

• Heartburn
• Regurgitation
• Difficulty swallowing
• Chest pain
• Anemia
• Chronic cough

Heartburn: Symptomatic patients with hiatal hernia present with reflux disease and complain of heartburn, mostly after eating or at night. About 80 percent of patients with a paraesophageal hiatal hernia (type II hiatal hernia) have heartburn and have an increased amount of acid detected on pH monitoring (studies that detect acid in the esophagus).

Regurgitation: Foods can remain in the hiatal hernia and return back into the mouth. Type II and type III hiatal hernia can result in mechanical obstruction of the lower part of the esophagus, causing regurgitation of the food into the mouth after eating. This can be associated with a bitter taste in the mouth in patients with reflux disease.

Dysphagia (difficulty swallowing): Hiatal hernias can cause obstruction and delay in emptying of the lower part of the esophagus and the stomach, resulting in dysphagia.

Chest pain: The chest pain commonly occurs postprandially (after eating) and is substernal (behind the breast bone) in location, giving rise to concern that the chest pain is cardiac in origin.

Anemia: Anemia is the most common laboratory finding in patients with paraesophageal (type II) hiatal hernia, and results from damage and ulceration to the lining of the stomach due to compression of the stomach at the level of esophageal hiatus (see image below).

Chronic cough: Chronic cough is caused by aspiration of acid particles in the airway. It is also known that the presence of acid in the esophagus can cause a reflex phenomenon in the airway and cause cough.

Diagnosis

CXR: A shadow behind the heart on a routine chest film is a common mode of discovery of paraesophageal hernia (see image below).

Videoesophagram: This study shows the anatomy of the gastroesophageal junction, the position of the stomach and the presence of other intra-abdominal organs in the chest. In addition, a videoesophagram reveals the esophageal emptying. A large paraesophageal hernia is shown on a barium esophagram in the image below.

Upper endoscopy: An upper endoscopy can reveal the presence of a hiatal hernia and allows an assessment of the damage to the lining of the esophagus and the stomach. The image below shows an endoscopic view of a sliding (type I) hiatal hernia.

The image below shows an endoscopic view of a type III hiatal hernia.

Esophageal motility study: This study measures the pressure in the lower esophageal sphincter (the valve between the esophagus and the stomach) and the function of the esophageal body.

Esophageal pH study: We routinely obtain a 24-hour esophageal pH study or a 48-hour Bravo capsule wireless pH study to detect the amount of acid in the esophagus in patients with symptomatic hiatal hernia and gastroesophageal reflux disease. We do not routinely perform a pH study in patients with large paraesophageal hernia, since the result will not change our management in symptomatic patients, and the placement of a catheter is challenging and uncomfortable for the patients.

Treatment

Patients with a small sliding hiatal hernia (type I hiatal hernia) who have no symptoms, do not require any treatment and can be observed closely. The treatment of large sliding hiatal hernia and paraesophageal hernias requires surgery to correct the anatomy, reduce the hernia and repair the opening in the diaphragm (crural opening).

Traditionally, large sliding hiatal hernias and paraesophageal hiatal hernias were repaired through a thoracotomy (incision in the chest) or laparotomy (a large incision in the abdomen) with a morbidity of 20 percent and a mortality of 2 percent. The development of laparoscopic surgery has led to the repair of these complicated hernias by a minimally invasive approach, with five small incisions. The procedure is called laparoscopic Nissen fundoplication and is routinely performed at the Memorial Hermann Southeast Esophageal Disease Center for the treatment of patients with gastroesophageal reflux disease.