What is a hiatal hernia?
A hiatal hernia occurs when part of the stomach, which normally resides in the abdomen moves upward through an enlarged opening in the diaphragm into the chest cavity. This type of hiatal hernia is called a sliding hiatal hernia. While there are other types of hiatal hernia, this is the type most commonly associated with GERD and is the focus of this article.
The esophagus normally passes through a rather small opening in the diaphragm (the muscular structure separating the chest or thorax from the abdomen) to join the stomach in the abdomen. If this opening, which is called the hiatus, enlarges or dilates, it becomes large enough to allow a small or even large part of the stomach to pass through it into the chest. This can represent only a tiny amount of the upper stomach (as little as 2 or 3 centimeters-less than 1 inch), or a larger portion of the upper stomach; in extreme cases, almost the entire stomach comes to reside in the chest cavity instead of the abdomen where it belongs.
How hiatal hernia is diagnosed?
A hiatal hernia is diagnosed by tests that look at anatomy such as upper endoscopy or barium UGI studies. The diagnosis of GERD usually requires tests that look at the amount of acid reaching the esophagus, such as a pH study.
What you should know if you’ve been diagnosed with a hiatal hernia
Several things are essential to know about hiatal hernias in order to interpret and clarify what you may have been told by your physician or even read elsewhere.
- The term hiatal hernia and hiatus hernia are used interchangeably and mean exactly the same thing.
- Hiatal hernias are extremely common. In fact, by age 50, about 50% of individuals have at least a small hiatal hernia.
- Hiatal hernias, particularly small ones are usually asymptomatic and you would never know you have one.
- The presence of a hiatal hernia does not necessarily mean you have gastroesophageal reflux (GERD). However, a significant misunderstanding often occurs over this terminology. If you tell a physician that you have heartburn, the reply is often, “You may have a hiatal hernia.” They use the words hiatal hernia to mean GERD. This is incorrect and often creates confusion and a misunderstanding on the part of a patient. The reply should be that “You may have GERD.” The terms GERD and hiatal hernia are used in a way that suggests they are the same thing. Not all patients with GERD have a hiatal hernia and not all patients with a hiatal hernia have GERD! A hiatal hernia simply describes a very common anatomic abnormality, often with no consequences.
What is the relationship between hiatal hernia and GERD?
Hiatal hernia as a consequence of longstanding GERD
GERD is a disease that progresses through various stages over periods of years, and a hiatal hernia can be a consequence of longstanding GERD. As the disease progresses, the lower esophageal sphincter (LES) loses its function. It cannot “squeeze” and function as a barrier to reflux. As this happens, the lower esophagus at the site of the LES dilates and the shape of the upper stomach is altered. The result is the enlargement of the opening in the diaphragm discussed above, leaving room for the top of the stomach to move upward into the chest. In this case, a hiatal hernia is a consequence of longstanding GERD. In addition, due to the difference in pressure between the chest cavity and the abdomen, movement of the stomach and lower esophagus upward causes an already poorly functioning LES to get even worse. The hernia makes the preexisting “bad” valve worse and consequently GERD symptoms worsen.
The hiatal hernia itself causes symptoms of GERD
Another situation is also seen. If a person has a large hiatal hernia, they can have symptoms of GERD such as heartburn, but they can also have symptoms just from the distorted anatomy in having the wrong organ (stomach) in the wrong place (chest instead of abdomen). These symptoms can include chest pressure and pain, back pain, quickly getting full while eating, and others. The hernia itself, rather than GERD (which may or may not be present), causes these symptoms.
Hiatal hernia without GERD
There are several other causes of a hiatal hernia, but if the LES is functioning normally, there is no GERD. “Normal” anatomy is altered (hernia), but there is no disease (GERD).
Hiatal hernia is not synonymous with GERD
Although it is present in many patients with GERD and often makes GERD symptoms worse, a hiatal hernia is not synonymous with GERD. Small hiatal hernias are extremely common and are usually asymptomatic. “Mechanical” symptoms can be caused by a large hernia, which may or may not be accompanied by GERD symptoms. How a hiatal hernia is treated depends largely on which of the above situations exist.