Training in esophageal peroral endoscopic myotomy (POEM) on an ex vivo porcine model: learning curve study and training strategy.

Abstract

Peroral endoscopic myotomy (POEM) is a very effective treatment for achalasia. However, training remains non-standardized. We evaluated a training curriculum, including ex vivo cases, followed by patients' cases under expert supervision. The objective was to establish a learning curve of POEM. Four operators having completed advanced endoscopy fellowship were involved. They had already observed > 30 cases performed by experts. They performed 30 POEMs standardized (tunnel and myotomy lengths) procedures on ex vivo porcine model. Procedural times, number/volume of injections, mucosal and serous perforations, and myotomy length were collected. The learning curve was assessed using dissection speed (DS) and a dedicated performance score (PS), including learning rate (LR) and learning plateau (LP). The operators completed all cases within 4months (median of 3.5 cases/week). The mean procedural time was 43.3min ± 14.4. Mean myotomy length was 70.0mm ± 15.6mm. Dissection speed averaged 1.78mm/min ± 0.78. Using DS and PS as parameter, the LR was reached after 12.2 cases (DS = 2.0mm/min) and 10.4 cases, respectively. When comparing the LP and the plateau phase, the DS was slower (1.3 ± 0.5mm/min versus 2.1 ± 0.54mm/min, p < 0.005) and perforations were decreased: 0.35 ± 0.82 in LP vs. 0.16 ± 0.44 in PP. Following this training, all operators performed 10 supervised cases and are competent in POEM. The association of observed cases and supervised ex vivo model training is effective for starting POEM on patients. The learning curve is 12 cases to reach a plateau.