Peroral endoscopic myotomy for advanced achalasia with megaesophagus

Background The outcomes of peroral endoscopic myotomy for advanced achalasia are not well known. This study aimed to evaluate the outcomes of peroral endoscopic myotomy for achalasia with megaesophagus, which is one of the characteristics of advanced achalasia. Methods In total, 234 patients with achalasia who underwent peroral endoscopic myotomy in our hospital from April 2015 to March 2019 were included in this retrospective observational study. Megaesophagus was defined as a maximum esophageal diameter of 6 cm or more. Outcomes, including clinical success (Eckardt score ≤ 3 without retreatment) at the 1-year follow-up, technical success, and perioperative complications, were investigated and compared between patients with and without megaesophagus. Results Eleven patients (4.7%) were diagnosed with megaesophagus. The clinical success rate achieved was 63.6% in patients with megaesophagus, with a significant decrease in the Eckardt score (6 vs. 2, p = 0.003) and integrated relaxation pressure (28 mmHg vs. 9 mmHg, p = 0.028). The technical success rate was 100%. However, patients with megaesophagus had a significantly lower clinical success rate than those without megaesophagus (63.6% vs. 96.0%, p = 0.002). Furthermore, patients with megaesophagus had significantly higher rates of major adverse events than those without megaesophagus (18.2% vs. 2.7%, p = 0.048). Conclusions Peroral endoscopic myotomy improved achalasia-related symptoms, and this was technically feasible in patients with megaesophagus. However, the clinical success rate was somewhat low, and the rate of major adverse events was high. Therefore, peroral endoscopic myotomy should be carefully performed for advanced achalasia with megaesophagus.