Blown-out myotomy: an adverse event of laparoscopic Heller myotomy and peroral endoscopic myotomy for achalasia

• Published in: Gastrointestinal endoscopy Vol. 93; no. 4; pp. 861 - 868.e1
• Main Authors: Triggs, Joseph R., Krause, Amanda J., Carlson, Dustin A., Donnan, Erica N., Campagna, Ryan A.J., Jain, Anand S., Kahrilas, Peter J., Hungness, Eric S., Pandolfino, John E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2021
• Subjects: Esophageal Achalasia - surgery; Esophageal Sphincter, Lower - surgery; Heller Myotomy - adverse effects; Humans; Laparoscopy; Myotomy; Natural Orifice Endoscopic Surgery - adverse effects; Treatment Outcome; LHM; BOM; HRM; POEM; IRP; EGJ; DCI; IQR; LES; ES; BMI
• ISSN: 0016-5107; 1097-6779
• DOI: 10.1016/j.gie.2020.07.041

Although laparoscopic Heller myotomy (LHM) or peroral endoscopic myotomy (POEM) is highly effective, 10% to 20% of patients with achalasia remain symptomatic after treatment. In evaluating such patients, we have observed a pattern of failure associated with a pseudodiverticulum, or blown-out myotomy (BOM), in the distal esophagus. We aimed to assess risk factors and patient-reported outcomes associated with a BOM. We reviewed our manometry database for patients with achalasia previously treated with LHM or POEM. We included patients who had a post-treatment esophagram within 1 year of their follow-up manometry. A BOM was defined radiographically as a wide-mouthed outpouching (>50% increase in esophageal diameter) in the area of the myotomy. One hundred twenty-nine patients with achalasia who underwent treatment were included; 23 (17.8%) had a BOM. Comparing patients with a BOM with those without, post-treatment Eckardt scores were significantly greater (5 vs 2, P = .002), type III achalasia was more common (39.1% vs 14.2%, P = .005), and LHM was more common than POEM (73.9% vs 26.1%, P = .013). The integrated relaxation pressure was also significantly greater in the BOM group (15.0 mm Hg vs 11.0 mm Hg, P = .025). BOM is a common adverse event after myotomy for achalasia but is not seen after pneumatic dilation. Pretreatment type III achalasia, LHM as opposed to POEM, and a greater post-treatment integrated relaxation pressure were risk factors for developing a BOM. We speculate that esophageal wall strain in the area weakened by myotomy, whether from residual spastic contractility or continued esophageal outflow obstruction, may be the underlying mechanism of BOM development.