Per-oral endoscopic myotomy for achalasia: An American perspective

Table 1 Per-oral endoscopic myotomy equipment

High-definition diagnostic gastroscope

Transparent 4 mm distal cap attachment

Electrosurgical device for injection of saline, incision and cautery ( T-type HK hybrid knife- with Erbe jet pump)

Electrosurgical device for incision and cautery (Triangle tip knife) and injection of saline with Injector force Max 4 mm, 23-gauge injection needle

Electrosurgical high frequency generator (e.g., ERBE VIO 300D)

Coagulation 5 mm grasper (Olympus)

Endoscopic clips (Boston-Scientific, Olympus, Wilson-Cook)

Needle or trocar for potential decompression of capnoperitoneum (angiocatheter, Veress needle 120 mm)

Endoscopic dilating balloons- CRE balloon dilator (5.5 cm, 10-11-12 mm) multiple manufacturers (rarely required)

Submucosal injection: Methylene blue or indigo carmine diluted in saline

CRE: Controlled radial expansion.

Table 2 Evolution of per-oral endoscopic myotomy: A single center experience

Initial	Subsequent	Rationale
Performed in operating room with surgeon present	Performed in endoscopy suite with surgeon available	Demonstrated to be a predictable and safe procedure. Moderate procedural time
Selected patients had no prior achalasia intervention	Selected patients include those with prior intervention (BTI, PD, HM)	POEM results here and elsewhere
Use of dilation balloons to dissect submucosal tunnel	No or little use of balloon. Evolution from needle knife to IT knife and now hybrid knife	Experience. More reliable dissection with knives. Hybrid knife with flushing capability
Variable orientation of initial incision site	Preference for 5 o’clock position	Improved dysphagia relief
Short myotomy-less than 6 cm	Myotomy tailored to manometry findings and components of Eckardt score	POEM results here and elsewhere
Partial LES myotomy of circular muscle only	Preference for complete myotomy unless low LESP on manometry	Concern for POEM efficacy. Post-POEM GERD usually manageable with medication

POEM: Per-oral endoscopic myotomy; BTI: Botulinum (Botox) injection; LESP: Lower esophageal sphincter pressure; PD: Pneumatic dilation; HM: Heller myotomy; GERD: Gastroesophageal reflux disease.

Table 3 Per-oral endoscopic myotomy experience: Series data

No. of patients

No. of completed POEMs

Age (mean, yr)

Achalasia by HRM subtype

I

II

III

Esophageal dilation > 6 cm or sigmoid

Percent of patients who failed prior conventional achalasia treatment (Endoscopic balloon dilation, Botulinum toxin injection, Heller myotomy)

Pre/Post eckardt score (mean)

Percent of patients with clinical success at 3 mo (Eckardt score £ 3)

Myotomy length (mean, centimeter)

Percent of technical errors

Minor mucosal perforations requiring clip closure

Needle decompression of capnoperitoneum

Percent of adverse events

Surgical intervention/conversion

ICU or step down unit stay

Prolonged hospital stay > 5 d

Significant blood loss or blood transfusion

POEM related readmission

POEM: Per-oral endoscopic myotomy; HRM: High resolution manometry; ICU: Intensive care unit.