Q. A 63-year-old woman presents to the clinic with a six-month history of progressively worsening difficulty swallowing, initially with solid foods and now with liquids. She reports a history of heartburn but no significant weight loss, coughing, or choking while eating, and describes a sensation of food 'sticking' in her mid-chest area. Her medical history includes hypertension, for which she is currently medicated. She does not smoke or consume alcohol. Her vitals are normal and the physical examination is unremarkable. What is the most appropriate next step in her management?