The cardia is a part of the body's digestive system. Often called the cardiac section or heart of the stomach, it is the opening which provides a pathway for food to pass down into the stomach. Located near the top of the stomach, it connects the esophagus to the stomach. The esophagus is a tube made of muscle that allows food to travel from the mouth to the stomach to be digested.
Just above the cardia is a structure called the gastroesophageal sphincter, also known as the cardia sphincter. This valve-like muscle opening allows for food to pass through the esophagus and down to the stomach. Contraction of these muscles closes the top of the stomach and prevents the stomach contents from traveling back up. Problems can arise when this valve does not work properly.
When the gastroesophageal sphincter isn't working properly, acids from the stomach can move up into the esophagus. In the esophagus, stomach acid can irritate the lining, leading to pain and burning in the chest area, excessive saliva production, and nausea. This condition is known as gastroesophageal reflux syndrome (GERD), commonly referred to as heartburn or acid reflux. In chronic cases of heartburn, the lining becomes damaged. In extreme cases the upper portion of the stomach can protrude into the abdomen due to excessive fluid collection, causing what is known as a hiatal hernia.
Another problem which can arise from improper functioning of the cardia and gastroesophageal sphincter is called achalasia or cardiospasms. This occurs when the muscles cannot fully relax. Symptoms of achalasia include difficulty swallowing, chest pain, coughing, regurgitation, and aspiration. Aspiration is when food or liquids enter the lungs instead of the stomach.
The risk of esophageal cancer can increase with chronic GERD, which in turn can cause Barrett’s esophagus. This is a chronic irritation and change in the lining of the esophagus. Problems with esophageal cancer can occur if a tumor is blocking the entrance of the stomach. In extreme cases where removal of the tumor is unsuccessful, a surgical procedure called a cardiactomy is performed. This is where the cardia is removed.
If the structure is removed, an artificial one can be used. This is a method to maintain the opening between the esophagus and stomach, and assist in the functioning of the gastroesophageal sphincter. This can also be used to help prevent or fight GERD, esophageal cancer, and achalasia.