Functional esophagogastric junction obstruction with intact peristalsis: A heterogeneous syndrome sometimes akin to achalasia

Background: Some patients with suspected achalasia are found on manometry to have preserved peristalsis, thereby excluding that diagnosis. This study evaluated a series of such patients with functional esophagogastric junction (EGJ) obstruction. Methods: Among 1,000 consecutive high-resolution manometry studies, 16 patients had functional EGJ obstruction characterized by impaired EGJ relaxation and intact peristalsis. Eight patients with post-fundoplication dysphagia and similarly impaired EGJ relaxation were studied as a comparator group with mechanical obstruction. Intrabolus pressure (IBP) was measured 1 cm proximal to the EGJ. Sixty-eight normal controls were used to define normal IBP. Patients' clinical features were evaluated. Results: Functional EGJ obstruction patients presented with dysphagia (96%) and/or chest pain (42%). IBP was significantly elevated in idiopathic and post-fundoplication dysphagia patients versus controls. Among the idiopathic EGJ obstruction group treated with pneumatic dilation, BoTox^TM, or Heller myotomy, only the three treated with Heller myotomy responded well. Among the post-fundoplication dysphagia patients, three of four responded well to redo operations. Conclusion: Functional EGJ obstruction is characterized by pressure topography metrics demonstrating EGJ outflow obstruction of magnitude comparable to that seen with post-fundoplication dysphagia. Affected patients experience dysphagia and/or chest pain. In some cases, functional EGJ obstruction may represent an incomplete achalasia syndrome.