INCOMPLETE MYOTOMY DUE TO EXTRAMUSCULAR DISSECTION DURING THE POEM: DESCRIPTION AND DETECTION OF A PROCEDURE FAILURE

Aims:

Incomplete myotomy is rare during the POEM for achalasia. An extramuscular dissection can lead to this technique failure. We present a videocase and analyze the images for its detection.

Methods:

Video review of a case of failed POEM in a patient with type 2 achalasia.

Results:

During the tunneling phase of POEM, intense spasticity was observed in the lower esophageal sphincter area. It hindered the mobilization of the endoscope and entailed an increased risk of mucosal tear. Therefore, the myotomy was started without completing the tunnel, in order to partially relax this spasticity. Within the spastic area, a complete myotomy was observed. Dissection was continued observing an open space, similar to the subcardial area, but with abundant fatty tissue, vascularization and friability. The procedure was terminated although doubts about complete myotomy were raised. Clinical follow-up was suggestive of uncomplete myotomy. Revision of the video recording detected unintentional extramuscular dissection and incomplete myotomy. The observation of the margins of the myotomy is critical to detect this incidence.

Conclusions:

1. Myotomy prior to complete tunneling of the submucosa may increase the risk of an extramuscular dissection.

2. Extramuscular dissection images can be misinterpreted as a complete myotomy.

3. The observation of the myotomy edges facilitates the detection of the extramuscular dissection.

4. Video documentation of all cases and revision of failed cases is crucial to analyzed failed POEM procedures.