Symptoms and Quality of Life in Patients With Heterotopic Gastric Mucosa (HGM)

Inclusion Criteria: * Planned upper gastrointestinal endoscopy (gastroscopy) for clinical reasons (any indication) * Age ≥ 18 years * Written informed consent * Ability to complete the study questionnaires prior to endoscopy Exclusion Criteria: * Previously known heterotopic gastric mucosa (HGM) * Previously diagnosed dysphagia with prior therapeutic intervention (including pre-established diet modification, partial oral/enteral nutrition, steroid therapy, botulinum toxin injection, etc.) * Mechanical ventilation * Presence of a tracheostomy * Inadequate endoscopic assessability of the proximal esophagus, including: * General condition insufficient for careful endoscopic inspection (investigator's judgement) * Increased risk of aspiration * Inadequate visibility during the procedure (e.g., bleeding, food residue) * Complications preventing careful inspection of the proximal esophagus * History of surgery involving the pharynx or esophagus * Relevant severe neurological disorder (e.g., ALS, stroke) * Severe dementia * Severe depressive disorder * Lack of cooperation / inability to comply with study procedures * Planned PEG placement * Emergency endoscopy