Aim: To investigate the nature and origin of cardiac mucosa (CM).
Methods: Biopsy samples from sixty-one individuals were included in this study. The specimens were taken "at", "just below", or "just above" the gastroesophageal junction, including the histologic squamocolumnar junction. Clinical data were obtained by reviewing electronic medical records for each patient. Patients with a history of stomach adenoma or carcinoma and esophageal carcinoma were excluded, and cases that were endoscopically suspicious of Barrett's esophagus or a polyp were also ruled out. Histologic and endoscopic reviews were performed blinded to the patient's clinical data. Histologic evaluation was conducted by two pathologists, and endoscopic review was performed by a endoscopist with wide experience in the field. Histologically, the columnar epithelium of squamocolumnar junction, presence and severity of acute and chronic inflammation, atrophy, intestinal metaplasia, and presence of carditis were evaluated. Endoscopically, reflux esophagitis was evaluated by Los Angeles (LA) classification, hiatal hernias were classified by Hill grade, and gastroesophageal flap valves were assessed.
Results: Fifty-nine of the 61 (96.7%) patients were Korean; 65.6% (40/61) of the patients underwent endoscopy according to the schedule of the National Health Insurance Program as a screening inspection. Of these, only 20.0% (8/40) of cases had reflux symptoms. CM was present in 41/61 (67.2%) individuals, and its presence was associated with older age compared to oxyntocardiac mucosa/oxyntic mucosa (60.59 ± 2.02 years vs 51.55 ± 3.35 years; P = 0.018). The presence of CM was associated with endoscopic diagnosis of esophagitis according to the LA classification (P = 0.022). CM was associated with mononuclear cell infiltration and neutrophilic infiltration, which were statistically significant (P = 0.001, and P = 0.004, respectively). The inflammation of CM, "carditis", showed a statistically significant association with endoscopic diagnosis of reflux esophagitis according to the LA classification (P = 0.008).
Conclusion: CM at the gastroesophageal junction is a common histologic finding in biopsy specimens, though not always present, and associated with gastroesophageal reflux disease and carditis severity.
Keywords: Cardiac mucosa; Carditis; Gastroesophageal junction; Gastroesophageal reflux disease; Histopathology.