Peroral Endoscopic Myotomy (POEM) For Achalasia Patients With Prior Endoscopic Therapy

Background and Aims Peroral endoscopic myotomy(POEM) as a recently developed treatment method for Achalasia(AC) is outstanding and recognized. In clinical work, a portion of AC patients received other endoscopic therapy for AC (such as botulinum toxin injection, pneumatic balloon dilation) or even POEM or LHM before receiving POEM.This study aimed to explore safety and efficacy of patients with AC who underwent POEM with previous endoscopic treatment history and find out the potential factor relating to safety and efficacy of POEM for AC by the large volume cases. Methods Clinical data of 439 AC patients who had a treatment of POEM in our endoscopy center from december 2010 to december 2015 were retrospectively analyzed. The patients were divided into four groups:the botulinum toxin injection group (subgroup:once group,?twice group),dilation group (subgroup:once group,?twice group), botulinum toxin injection & dilation group and einitial treatment group,according to the prior endoscopic treatment for AC. Analyzed the influences of the prior endoscopic treatment to the clinical efficacy and safety of POEM and selected the factors about the prognosis of POEM by the large volume cases.Results A total of 439 patients were enrolled, the median age was 47 years(range 13 to 77 years),sex ratio(male:female)1:1.15, procedure time was 43±17.5 (17?132) min,the total complication rate was 28.7%(126/439).To December 2015, treatment success (Eckardt score<3) with a follow-up for 1?48 months (median 6 months) was achieved in 94.5% of 364 cases.The Eckardt score of patients declined from 6.7±1.5(2?10) to 1.2±1.1(0?5)(P<0.05).After POEM,135 patients reviewed the highresolution manometry (HRM),compared with the preoperative,the remission rate of LESP was 91.1%(123/135),the average extent of decline was 50.3%,the remission rate of LESRP was 92.6%(125/135),the average extent of decline was 47.8%.Six patients exhibited partial esophageal body vermiculation recovery.There were 38 cases in botulinum toxin injection group (subgroup:once group 21 cases,?twice group 17 cases),65 cases in dilation group (subgroup:once group 51 cases,?twice group 14 cases),8 cases in botulinum toxin injection & dilation group and 325 cases in einitial treatment group.Because of the limited sample size,we merged the groups with prior endoscopic treatment into the retreatment group(total 111 cases).The success rates of POEM in two groups were 100% (111/111) and 99.4%(328/330), with no significant difference(P=1.0000). Twenty cases were found scar or synechia,the incidence rate of the retreatment group was significantly greater than that of einitial treatment group (9.9%,11/111 vs 2.7%,9/328, P=0.0018).The the total complication rates of POEM in two groups were (27.9%,31/111vs 29.0%,95/328), with no significant difference(P=0.8349). The statistic differences of Eckardt score among the groups and subgroups were not significant(P>0.05).Prior endoscopic treatment for AC before POEM did not impact on the decline of the low esophageal sphincter pressure(LESP) and low esophageal sphincter residual pressure (LESRP) after POEM(P>0.05).Logistic regression revealed that year of POEM[referring to 2015,before 2011 odds ratio(OR)=9.454,95%CI 2.499?35.76;2012 OR=2.177,95% CI 0.794?5.974;2013 OR=3.975,95% CI 1.904-8.298;2014 OR=1.079,95% CI 0.601?1.940]and approach of entry incision (referring to longitudinal entry incision,inverted T entry incision OR=0.369,95% CI 0.165?0.824;transverse entry incision OR=0.456,95% CI 0.242? 0.859) were the factors of complications.Approach of myotomy (referring to full-thickness muscle myotomy in combination with indwelling an anti-reflux belt,gradual full-thickness muscle myotomy OR=0.363,95% CI 0.059?2.250;circular muscle myotomy OR=2.137,95% CI?0.440?10.378;circular muscle myotomy in combination with balloon shaping OR=4.385,95% CI?0.820 ? 23.438;the recurrence rate of full-thickness muscle myotomy was 0)was the factor of symptomatic relapse.Conclusion AC relapsing patients who received botulinum toxin injection and/or dilation treatments for AC before POEM can also undergo POEM safely and availably.Complication rate of POEM were gradually declining over time,inverted T entry incision was the best choice in terms of control complications.Gradually full-thickness muscle myotomy was excellent in respects of relapse,procedure time and the incidence of reflux esophagitis.