Hospital GERD Center: Esophageal hiatal hernia (hiatus hernia) is a disease caused by the entry of intra-abdominal organs (mainly the stomach) into the thoracic cavity through the diaphragmatic esophageal hiatus. Esophageal hiatal hernia is the most common type of diaphragmatic hernia, accounting for about 90% or more of cases. The exact incidence of the disease is still unclear, as the symptoms are mild or absent, and the detection rate of upper gastrointestinal tract imaging is reported to be 0.8%-2.9%. The incidence is significantly higher in Western countries than in Asia. The incidence rate increases with age, from about 9% below the age of 40 to 69% above the age of 60. According to the location of the esophagogastric junction, esophageal hiatal hernia is divided into the following types 1. Sliding hernia: This type is the most common, accounting for about 75% to 90% of all esophageal hiatal hernia. The esophagogastric junction is herniated upward into the mediastinum through the esophageal hiatus, and the upper part of the stomach and the left gastric vessels and tissues may also be herniated. It usually appears when lying down and disappears when standing up. The sliding esophageal hiatus hernia does not have an intact hernia sac, the hernia is anterior to the peritoneum and posterior to the gastric wall. 2. Para-esophageal hernia: This type is less common and accounts for about 5% to 20% of hiatal hernias. A part of the stomach (fundus or body) enters the thoracic cavity through the esophageal hiatus (often located in the left anterior part of the hiatus), sometimes with herniation of the greater omentum, but the esophagogastric junction is still located under the diaphragm. Paraoesophageal hernia forms a complete hernia sac from the peritoneum, and because the pressure in the abdominal cavity is higher than that in the thoracic cavity, the hernia sac can gradually increase in size, and when more than 1/3 of the stomach herniates into the thoracic cavity, it is called a giant hiatal hernia. 3. Mixed hernia: it is the least common, accounting for less than 5%. Mixed hernia refers to the coexistence of sliding hernia and paraesophageal hernia, which mostly develops from paraesophageal hernia, often as a consequence of an oversized diaphragmatic esophageal hiatus. Because of the large hernia sac in this type, other organs such as omentum or colon are often herniated at the same time. 4. Short esophageal hiatal hernia: It is caused by the shortening of the esophagus (after esophagitis and other esophageal contractures or lower esophageal resection) pulling the gastric sac into the thoracic cavity, and behaves similarly to the sliding type, but the cardia is located on the diaphragm in either the prone or standing position. Sliding esophageal hiatal hernia may also appear as a “short esophagus” on barium x-ray or endoscopy, but this is due to the contraction of the longitudinal esophageal muscles as the cardia rises, and the esophagus may lengthen when standing, which is different from a true short esophagus. In addition, in congenital short esophagus, the esophagogastric junction is also located above the diaphragm, which should not be called a hiatal hernia, but is due to the fact that the lengthening of the esophagus stops in the thoracic cavity as the stomach migrates caudally during development. Congenital short esophagus can only be diagnosed if it is confirmed at surgery that the esophagogastric junction cannot descend below the diaphragm or that the blood supply to the stomach in the thoracic part should come directly from the aorta. Etiology and pathogenesis The occurrence of esophageal hiatal hernia is closely related to the anatomical structure in and around the esophagogastric junction. Under normal circumstances, the lower part of the esophagus is surrounded by an elastic fiber membrane, the diaphragmatic esophagus membrane, which is connected to the esophageal hiatus, forming a complete sealing ligament that prevents the esophageal antrum and cardia from prolapsing and prevents the cardia from being pulled to the diaphragm during deep inspiration or during strong contraction of the longitudinal esophageal muscles. The diaphragm. In addition, the lower esophagus and the esophagogastric junction are also secured to the esophageal hiatus by the upper and lower diaphragmatic esophageal ligaments and the gastrophrenic ligament, respectively. The main causes of esophageal hiatus hernia are as follows: (1) atrophy of the tissue around the hiatus and the elastic tissue of the diaphragmatic esophagus membrane, which causes relaxation and widening of the esophageal hiatus, and relaxation of the diaphragmatic esophagus membrane and/or the periesophageal ligaments, which lose their role in fixing the lower esophagus and cardia in their normal position. Most of the cases are due to aging or chronic diseases, and some are congenital dysplasia of the diaphragmatic foot or weakness of the diaphragmatic esophageal ligament. ②Increased intra-abdominal and intragastric pressure, such as obesity, ascites, pregnancy, habitual constipation, chronic cough, weight bearing, bending, violent vomiting, overeating and frequent eructation, etc., when the upper part of the stomach is easily pushed into the esophageal fissure and develops. Other less common causes include: thoracic and abdominal trauma or surgery that damages or tracts the tissues around the hiatal hernia, resulting in an enlarged hiatal hernia; long-term esophageal inflammation and ulceration that leads to fibrosis, and tumors of the lower esophagus that can cause acquired esophageal shortening (esophageal contracture), resulting in a tractional short esophageal hiatal hernia. In conclusion, for the development of esophageal hiatal hernia, relaxation and widening of the esophageal foramen is the basis for its formation, and increased intra-abdominal pressure is the most common causative factor. The main pathological changes that cause sliding esophageal hernia are relaxation of the diaphragmatic esophageal membrane, relaxation of the periesophageal ligament, weakening of the spring-like action of the diaphragmatic esophageal foramen and shortening of the esophagus due to various causes, while the main causes of paraesophageal hernia are widening of the esophageal foramen and increased intra-abdominal pressure. In paraoesophageal hernia (mainly sliding type), the esophagogastric junction is herniated into the thoracic cavity, causing the angle of the esophagogastric junction (His angle) to become blunt from the normal acute angle and the mucosa of the cardia to lose the anti-reflux barrier effect of the valve; at the same time, the lower esophageal sphincter (LES) is displaced into the thoracic cavity and loses its adaptive pressure-raising reflex in response to increased intra-abdominal pressure; the length of the abdominal segment of the esophagus is shortened, causing the pressure in the lumen of the entire segment to decrease. In addition, the spring-clamp-like effect of the diaphragmatic esophageal hiatus is weakened, which can lead to a weakened anti-reflux mechanism and pathological gastroesophageal reflux, which is the source of the main symptoms of a hiatal hernia. The hiatal hernia itself is often asymptomatic or only slightly uncomfortable, while the hernia sac may compress adjacent organs in the thoracic cavity when it is large. Paraesophageal hernia, because the fundus and body of the hernia sac are located on the diaphragm, the food and gastric acid inside it tend to accumulate due to poor drainage, resulting in impaired blood flow and stasis of the gastric mucosa inside the hernia, which can lead to serious consequences such as ulceration, bleeding, impaction, strangulation, and perforation. Mixed hernia has the characteristics of the first two types of hiatal hernia and can be complicated by complications of both types of hernia. Gastroesophageal reflux due to esophageal hiatal hernia can cause reflux esophagitis, which in turn can contribute to contraction of the longitudinal esophageal muscles and scarring contraction of the lower esophagus, leading to traction esophageal hiatal hernia. Therefore, reflux esophagitis and esophageal hiatal hernia are causal and mutually reinforcing. Clinical manifestations There are three main symptoms of esophageal hiatal hernia: symptoms of gastroesophageal reflux, symptoms of hernia sac compression and symptoms of complications. Different types of hiatal hernia have different clinical manifestations. Patients with sliding hiatal hernia are often asymptomatic and are only detected during barium x-ray imaging, while those with symptoms are mostly due to gastroesophageal reflux and, to a lesser extent, to the mechanical effects of the hernia; symptoms of paraesophageal hernia are mainly mechanical compression, which can be tolerated by patients for many years; symptoms of both can occur in mixed hernia. The severity of symptoms does not correspond exactly to the degree of esophagitis or the size of the hernia sac. (a) Gastroesophageal reflux symptoms manifest as pain in the cardiac fossa or retrosternal area, heartburn, acid reflux, regurgitation, epigastric fullness, belching, etc. The pain can be mild or severe, but in severe cases it is unbearable and can radiate to the neck, ear, upper chest, back, left shoulder and right shoulder. The symptoms may be triggered or aggravated by lying down, bending over, eating alcoholic and acidic foods, coughing, and satiety, and can be relieved by standing or belching. (2) Symptoms of hernia sac compression When the hernia sac is large, it compresses the heart, lungs and mediastinum, which may produce symptoms such as chest tightness, shortness of breath, palpitation, cough, cyanosis and even syncope. When compressing the esophagus, it may feel a feeling of eating stagnation or difficulty in swallowing behind the sternum. (C) Complication symptoms 1. Upper gastrointestinal bleeding: hiatal hernia with bleeding is mainly caused by esophagitis and hernia bursitis, mostly chronic with a small amount of oozing blood, manifested only as black stool, which can lead to anemia. In combination with severe esophagitis or esophageal or gastric ulcer, violent vomiting of blood may occur. 2. Perforation: In rare cases, the ulcer in the hernia sac may be perforated, manifesting as severe chest pain and shortness of breath, with a poor prognosis if it ruptures into the pleural or pericardial cavity. About 74% of gastric ulcers in diaphragmatic hernia are complicated by upper gastrointestinal bleeding, but perforation is rare, only about 7%. 3. Esophageal obstruction: The main manifestations are dysphagia, painful swallowing, and vomiting after eating, caused by esophagitis resulting in esophageal spasm or organic scarring stenosis. In patients with reflux symptoms, about 10-15% of organic esophageal strictures occur. 4. Hernia sac twisting and entrapment: rare. Larger paraesophageal hernias are prone to torsion or impaction because the fundus and body of the stomach herniate into the thoracic cavity, while the cardia of the stomach is below the diaphragm. It presents as sudden severe epigastric pain with vomiting, complete inability to swallow or simultaneous hemorrhage, and there is a risk of shock and death if not treated in time, and should be operated urgently. 5, esophageal coronary syndrome: the esophageal pain of this disease can stimulate the vagus nerve, reflexively cause the coronary artery supply is insufficient, the electrocardiogram shows myocardial ischemic changes, the patient may appear chest tightness, pressure in the precordial area, arrhythmia and other manifestations. The patient may experience chest tightness, pressure in the precordial region, and arrhythmia. The disease may be triggered or aggravated by pre-existing coronary heart disease. In the absence of complications, there are usually no special signs of esophageal hiatal hernia, and a bulbar and turbid zone can be percussed in the chest in giant hernias. Bowel sounds and splashing sounds can be heard in the chest after drinking or during vibration, and some patients have sternal or subxiphoid pressure pain. Patients with esophageal hiatal hernia are prone to develop symptoms associated with gallstone disease, chronic cholecystitis, peptic ulcer and intestinal diverticulosis. The coexistence of esophageal hiatal hernia, cholelithiasis and colonic diverticulum is called Saint’s triad, and the coexistence of hiatal hernia, gallbladder disease and peptic ulcer is called Casten’s triad. Auxiliary examination (a) Barium X-ray examination is an important tool for diagnosing esophageal hiatal hernia, and the diagnosis can be confirmed by this. 1. Supra-diaphragmatic hernia sac sign: On chest X-ray, a sac-like shadow can be seen on the left posterior side of the diaphragm and heart, which is round or oval in shape, usually with a diameter of >5cm, and can contain gas, and the liquid level can be seen in standing fashion. 2. Elevation and contraction of the lower esophageal sphincter ring (A-ring): the A-ring, which does not show on X-ray under normal circumstances, moves up and shows signs of contraction after the appearance of a hiatal hernia, which constitutes the upper end of the hernia sac and manifests as an annular contraction about 1 cm wide above the hernia sac, which helps to differentiate it from the diaphragmatic potbelly, because there is usually no restrictive annular contraction above the normal diaphragmatic potbelly. 3. A coarse and tortuous gastric mucosal wrinkled wall shadow is present within the supradiaphragmatic hernia sac and continues through the widened diaphragmatic esophageal fissure to the subdiaphragmatic gastric base. 4. The presence of an esophagogastric ring (B-ring, Schatski ring): a more characteristic sign of a sliding hiatal hernia. It is a symmetrical incision of varying depths on the wall of the hernia sac, formed by temporary contraction of the esophagogastric junction. The appearance of this ring indicates that the esophagogastric junction has moved up to the diaphragm, whereas in normal patients this ring is located below the diaphragm and is not easily revealed during barium examination. All of the above are the X-ray signs of sliding hiatal hernia. 5. Para-esophageal hernia: see incomplete image of gastric vesicle, part of which enters the diaphragm and is located in the left anterior part of the esophagus, which can cause a large indentation on the left anterior part of the lower end of the esophagus, while the cardia is still located under the diaphragm. 6. Mixed hiatal hernia: see the above two signs, the cardia is located on the diaphragm, the barium enters both the stomach under the diaphragm and the hernia sac on the diaphragm, the hernia sac is larger and can form an indentation on the esophagus. Sliding esophageal hiatal hernia, especially in mild cases, may not show the above-mentioned X-ray manifestations on routine examination, but it is also suggestive if the following indirect signs are present: ① widening of the diaphragmatic esophageal hiatus (>2 cm); ② barium reflux into the diaphragm; ③ blunting of the esophagogastric angle (His angle); ④ a pointed curtain in the gastroesophageal antrum. It is worth pointing out that since sliding hiatal hernia is not a fixed presence, a negative examination cannot exclude this disease; if there is a high clinical suspicion, the examination should be repeated several times and special positions should be adopted, and there are three commonly used ones: ① supine head-low-foot-high position while increasing abdominal pressure; ② prone position with a cushion under the upper abdomen and continuous administration of barium under gastric filling; ③ bending in lateral standing position after gastric filling. (b) Endoscopic examination Esophageal hiatal hernia mainly has the following manifestations under endoscopy: (i) retained fluid in the lumen of the esophagus; (ii) upward shift of the dentate line, which is often less than 38 cm from the incisors; (iii) enlargement and/or relaxation of the cardia opening; (iv) blunting of the His angle; (v) shallowing of the gastric fundus; (vi) indentation of the diaphragmatic esophageal hiatus, covered with congested, flushed gastric mucosa and sometimes erosive ulcers; (vii) often accompanied by reflux esophagitis. Endoscopy generally cannot directly observe hiatal hernia, so it is not used as a routine method to diagnose this disease, but complications such as reflux esophagitis and esophageal stricture can be observed and differentiated from other diseases accordingly. (iii) Esophageal kinetic examination Not necessary for diagnosis, but can be used as an auxiliary examination. Esophageal manometry may reveal pressure bimodality, upward shift of the LES, fluctuation of pressure at the gastroesophageal junction with sliding of the hernia, and a flat segment of elevated pressure when the manometry tube passes through the hernia sac. Esophageal pH monitoring at 24 h can indicate gastroesophageal reflux, which is of higher diagnostic value than X-ray examination. V. Treatment (a) Internal treatment Mainly anti-reflux and acid-reducing drugs are used for gastroesophageal reflux, while trying to eliminate factors favoring hernia formation. 1, life guidance low-fat diet, avoid eating too much, do not eat before bedtime, elevate the head of the bed during sleep, quit smoking and avoid alcohol and coffee, avoid bending and squatting, weight bearing, wearing tight clothes and other behaviors that increase abdominal pressure. 2, obese people should try to reduce weight, those with chronic cough, long-term constipation should try to treat; 3, anti-reflux drugs including prokinetic drugs (such as morpholine, cisapride), antacids, acid suppressants. Those with severe GERD symptoms should be treated with powerful acid suppressants – proton pump inhibitors (such as omeprazole) and combined with prokinetic drugs. (ii) Surgical treatment The following cases are suitable for surgical treatment: (i) those who have severe complicated esophagitis and the effect of medical treatment is not obvious; (ii) those who have complications of reflux esophagitis such as persistent gastrointestinal bleeding and esophageal stricture; (iii) those who have large hernia sacs with compression symptoms or frequent impaction; (iv) those who have acute impaction or even strangulation and other emergency conditions; (v) those who advocate surgical treatment for paraesophageal hiatal hernia once the diagnosis is established. The aim of surgical treatment is to repair the widened diaphragmatic esophageal hiatus and to reconstruct the anti-reflux mechanism in the gastroesophageal junction area to prevent hernia formation and correct gastroesophageal reflux. There are many types of surgical procedures, and the main methods are: (1) repair of the esophageal hiatus; (2) esophageal and cardia fixation; (3) gastric fixation with anterior fundoplication; and (4) highly selective vagotomy. Each of these procedures has its own advantages and disadvantages, and the overall results are not very satisfactory. At present, most scholars believe that the effectiveness of surgery depends on whether the LES function is restored to normal or not.