1833 Utilization of EndoFLIP to Diagnose Achalasia in a Patient With Chronic Dysphagia Previously Attributed to Dysphagia Lusoria

INTRODUCTION: Dysphagia lusoria is a rare cause of dysphagia resulting from compression of the esophagus due to an aberrant right subclavian artery. Less than 2% of the population have this anatomic variant and the majority are asymptomatic. An aberrant right subclavian artery may not be clinically significant in a patient with concurrent esophageal pathology. CASE DESCRIPTION/METHODS: An 87-year-old woman with a twenty year history of chronic dysphagia complicated by recurrent food impactions presented with poor oral intake and weakness. Previously attributed to paraesophageal hernia, the dysphagia persisted despite partial fundoplication surgery. Prior CTA abdomen was suggestive of dysphagia lusoria, identifying an aberrant origin of the right subclavian artery traversing behind a dilated esophagus with associated mass effect. Achalasia was previously suspected but never confirmed as the patient could not tolerate the manometry procedure. EGD with EndoFLIP revealed a distensibility index of 0.6, a diameter of 5 mm, and a balloon pressure of 29 mm Hg with no appreciable peristalsis, consistent with type I achalasia. EUS revealed an aberrant right subclavian artery without extrinsic esophageal compression. EGD with pneumatic dilatation was performed after which the distensibility index was 6 with a diameter of 12.5 mm. The patient was placed on clear liquids and successfully transitioned to a pureed diet with significant symptomatic improvement. Outpatient follow up is pending. DISCUSSION: The EndoFLIP and EUS results confirmed the diagnosis of achalasia while simultaneously showing that the aberrant right subclavian artery represented an incidental finding rather than the true etiology of dysphagia. Moreover, it was the esophageal dilatation caused by achalasia that likely led to the discovery of the previously undetected aberrant subclavian vessel. Given the rarity of clinically significant dysphagia lusoria, it is important to consider alternative diagnoses in the evaluation of dysphagia. Molz G, Burri B. Aberrant subclavian artery (arteria lusoria): Sex differences in the prevalence of various forms of the malformations. Evaluation of 1378 observations. Virch Arch A Pathol Anat Histol 1978;380:303–15.