Zenker's peroral endoscopic myotomy (Z-POEM) for recurrent Zenker diverticulum: not so fast!

We congratulate Sanaei et al. for publishing their data on Z-POEM in 32 patients with recurrent Zenker diverticulum (ZD) [1]. We wish to discuss several observations.

First, Z-POEM involves cricopharyngeal myotomy with distal extension by 1 – 2 cm on the esophageal side to ensure complete dissection. This runs the risk of cutting the circular muscles of the esophagus, which has no longitudinal muscle layer or serosal lining, and therefore risks perforation. Indeed, serious adverse events occurred in 4/32 patients (12.5 %), including two leaks and two mucosotomies (perforations). These are potentially life-threatening complications, which seem disproportionate to the elective nature of these cases, performed mainly on patients with mild-to-moderate symptoms (dysphagia score, interquartile range 1 – 2).

Second, technical success was reported in 29 /30 patients. Given that two patients were excluded owing to technical failures, the success rate should be 29 /32 (90.6 %). Given that the median follow-up duration was 166 days, longer term outcome data remain warranted. This is because, unlike conventional septotomy, the mucosal bridge of the pouch is not dissected in Z-POEM, leaving behind a remnant pouch that can give rise to regurgitation symptoms in the long run.

Third, we recently found the Dysphagia, Regurgitation, Complication (DRC) score to be superior to the Dysphagia (Dakkak) score alone in ZD. Of note, regurgitation can be a particularly disabling symptom, even in the absence of dysphagia [2].

Finally, flexible endoscopic septal division (FESD) has been shown to effectively improve symptoms in recurrent ZD, with an excellent safety profile [2] [3] [4]. The recent ESGE guidelines still regard Z-POEM as experimental and recommend its use in a research setting for the time being [5].

We invite the authors’ views on the observations discussed above. Despite the promising data, we eagerly await the longer term safety and efficacy data before considering Z-POEM as the mainstream approach, even in recurrent ZD.

Publication History

Article published online:
24 June 2021

• References

• 1 Sanaei O, Ichkhanian Y, Mondragón OVH. et al. Impact of prior treatment on feasibility and outcomes of Zenker’s peroral endoscopic myotomy (Z-POEM). Endoscopy 2020; DOI: 10.1055/a-1276-0219.
• 2 Ishaq S, Siau K, Lee M. et al. Long-term success of flexible endoscopic septal division with the stag beetle knife for Zenker’s diverticulum: a tertiary center study. Dis Esophagus 2020; DOI: 10.1093/dote/doaa019.
• 3 Ishaq S, Hassan C, Antonello A. et al. Flexible endoscopic treatment for Zenker’s diverticulum: a systematic review and meta-analysis. Gastrointest Endosc 2016; 83: 1076-1089.e5
• 4 Ishaq S, Sultan H, Siau K. et al. New and emerging techniques for endoscopic treatment of Zenker’s diverticulum: State-of-the-art review. Dig Endosc 2018; 30: 449-460
• 5 Weusten BLAM, Barret M, Bredenoord A. et al. Endoscopic management of gastrointestinal motility disorders - part 2: European Society of Gastrointestinal Endoscopy (ESGE) Guideline. Endoscopy 2020; 52: 600-614