Despite theoretical preferences for either the anterior or the posterior approach to peroral endoscopic myotomy (POEM) in patients with achalasia, a new study has found no significant difference between the two in regard to clinical success or safety.
“Both approaches are equivalently safe when performed by experienced operators,” wrote Mouen A. Khashab, MD, of Johns Hopkins Medicine in Baltimore and coauthors, adding that the most notable difference was “closure was rated as easier during the posterior approach,” and fewer clips were needed. The study was published in Gastrointestinal Endoscopy.
To analyze and compare the efficacy of the two POEM approaches, the researchers conducted a multicenter controlled clinical trial of 150 patients with achalasia. They were randomized into two groups: those receiving POEM with the anterior approach (n = 73) or the posterior approach (n = 77). Of those patients, 148 received POEM and 138 completed 1-year follow-up. At 3, 6, and 12 months’ follow-up by phone call, patients were evaluated via outcomes that included Eckardt and dysphagia scores, quality of life scales, and gastroesophageal reflux disease questionnaire score.
Technical success was achieved in all 77 patients in the posterior group compared with 71 patients (97.3%) in the anterior group (P = .23). Both groups had a median length of hospital stay post procedure of 2 days. Adverse events occurred in seven patients (9%) in the posterior group and in eight patients (11%) in the anterior group (P = .703).
Though no significant differences were found between the two groups in time to perform mucosal incision, submucosal tunneling, myotomy, or closure, the median difficulty of closure in the posterior group was lower than in the anterior group (P = .002). In addition, fewer clips were needed during closure in the posterior approach.
After per-protocol analysis, clinical success at 1 year was achieved in 89% of patients in the posterior group (95% confidence interval, 81%-96%) and 90% of patients in the anterior group (95% CI, 82%-97%). At 1-year follow-up, both groups had an Eckardt score of 0 (P = .994) and their median gastroesophageal reflux disease score was 6 (P = .73). All patients who completed quality of life questionnaires reported improvements, with a median change in pain of 23 in the anterior group and 34 in the posterior group (P = .49). The posterior group also reported a greater median change in social functioning (50 vs. 38; P = .02).
The authors noted their study’s potential limitations, including relying on the Eckardt scoring system – one that was recently questioned in terms of validity – to determine clinical success. However, they also offered an argument in favor of clinical scoring because of “the importance of symptom improvement from the patient perspective.” Also, because of the lack of prestudy data comparing the anterior and posterior approaches, they chose 15% as the noninferiority margin for clinical efficacy, which could be regarded as a limitation as well.
Four of the authors reported potential conflicts of interest, including serving as consultants for various medical companies, serving on medical advisory boards, and receiving research support and personal fees. The other authors reported no conflicts of interest.
SOURCE: Khashab MA et al. Gastrointest Endosc. 2019 Aug 10. doi: 10.1016/j.gie.2019.07.034.
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