Introduction: Dysphagia lusoria is a rare disorder found in only a small percentage of individuals with an anomalous right subclavian artery causing extrinsic compression of the esophagus. Diagnosis often requires a comprehensive evaluation of dysphagia and a high index of suspicion. We present a case of dysphagia lusoria followed by a review of the pathogenesis, clinical presentation, and management of this rare condition. Case Description/Methods: A 36-year-old female was admitted to our hospital with severe sepsis secondary to a UTI. During her hospitalization, she complained of progressive dysphagia to solids for approximately 6 months. She reported intermittent globus sensation and reflux for many years. An upper endoscopy was performed and revealed a pulsatile narrowing of the proximal esophagus. Gastric and esophageal biopsies were negative. CT angiogram identified possible extrinsic esophageal compression by an aberrant right subclavian artery (ARSA). High-resolution manometry demonstrated impression at the level of the upper esophagus with an increased pressure band likely due to the ARSA. Overall impedance to solids and liquids was normal and no underlying dysmotility was identified. A diagnosis of dysphagia lusoria was made based on these findings. Unfortunately, dietary modifications and maximal medical therapy proved ineffective. Due to the severity of her symptoms, surgical repair of the aberrant vessel was ultimately recommended. Discussion: Involution of the fourth vascular arch during embryogenesis leads to the formation of the ARSA from the persisting dorsal aortic arch distal to the left subclavian artery. Because the vessel most commonly crosses between the esophagus and vertebral column, retroesophageal compression can occur. However, dysphagia lusoria is an exceedingly rare cause of dysphagia in adults. A thorough evaluation of dysphagia with endoscopic, radiologic, and manometric testing is necessary to rule out other potential etiologies before the diagnosis can be made. Patients often complain of solid-food dysphagia (most common), regurgitation, postprandial bloating, chest pain, and coughing. Treatment strategies depend on the severity of symptoms, response to conservative therapies, and candidacy for surgical intervention. Mild symptoms can often be managed using a combination of dietary and lifestyle modifications and medical therapy. Surgical evaluation for repair of the aberrant vessel is indicated for severe or refractory symptoms.Figure 1.: Figure A. Upper endoscopy demonstrating extrinsic compression of the proximal esophagus. The narrowed segment was measured at 18 cm from the incisors and had a pulsatile appearance. Figures B & C. Computed tomography angiogram of the chest (axial and coronal cuts) demonstrating the aberrant right subclavian artery (yellow arrows) with its origin from the distal aortic arch. Figure D. High-resolution manometry study demonstrating impression with an increased pressure band in the upper to mid esophagus caused by the aberrant right subclavian artery. Overall impedance to solids and liquids was within normal limits (90% complete clearance of liquid bolus swallows) with normal esophageal motility (9/10 swallows had normal contraction pattern with a mean DCI of 3127 mmHg-s-cm).