hiatal hernia
Summary
Hiatal hernia occurs when part of the stomach protrudes through the esophageal hiatus of the diaphragm into the thoracic cavity. There are two main types: sliding (95%, most common) and paraesophageal (5%). Sliding hiatal hernias are strongly associated with GERD due to disruption of the lower esophageal sphincter's anti-reflux mechanism.
Detail
Pathophysiology: The esophageal hiatus is an opening in the diaphragm through which the esophagus normally passes to join the stomach. Weakening of the phrenoesophageal ligament and widening of the diaphragmatic hiatus allow gastric herniation. Risk factors include obesity, pregnancy, aging, chronic increased intra-abdominal pressure (coughing, straining), and connective tissue disorders.
Types: 1. Sliding hiatal hernia (Type I, ~95%): The gastroesophageal junction and proximal stomach slide upward through the hiatus into the thorax. This displaces the lower esophageal sphincter (LES) into the chest, impairing its function and the normal angle of His, predisposing to GERD. 2. Paraesophageal hernia (Type II-IV, ~5%): The gastroesophageal junction remains in normal position, but the gastric fundus herniates alongside the esophagus through the hiatus. This type carries higher risk of complications like gastric volvulus, strangulation, and ischemia, and often requires surgical repair even if asymptomatic due to these risks.
Clinical presentation: Many are asymptomatic and found incidentally on imaging. Symptomatic patients present with heartburn, regurgitation, dysphagia, chest pain, or early satiety. Paraesophageal hernias may present with postprandial pain, vomiting, or signs of obstruction/strangulation (surgical emergency).
Diagnosis: Barium swallow study is classic for visualizing the hernia; upper endoscopy can also identify it and assess for esophagitis, Barrett's esophagus, or other complications. CT imaging may be used, especially for paraesophageal hernias.
Management: Sliding hernias with GERD symptoms are managed medically first with lifestyle modifications (weight loss, avoiding late meals, elevating head of bed) and PPIs/H2 blockers. Surgical management (Nissen fundoplication) is considered for refractory GERD or large hernias. Paraesophageal hernias, given their complication risk, often warrant surgical repair regardless of symptoms, especially if large or symptomatic.
High-yield associations: Hiatal hernia is a major risk factor for GERD, which can progress to esophagitis, Barrett's esophagus, and esophageal adenocarcinoma. Boerhaave syndrome (esophageal rupture) is a differential to consider in acute presentations, though distinct from hiatal hernia complications.
Sources
- First Aid for the USMLE Step 1
- Robbins Basic Pathology
- UpToDate: Hiatal hernia
- Sabiston Textbook of Surgery
Reviewed by AnkiBoss editorial — medical student review. Information here is for study reference only and is not medical advice. Spotted an error? Let us know.