目的:评估贲门失弛缓症(achalasia，AC)治疗失效患者行经口内镜下肌切开术(peroral endoscopic myotomy，POEM)的围手术期及远期疗效。方法:回顾性分析2010年8月—2014年12月在复旦大学附属中山医院内镜中心接受POEM治疗，并完成随访的849例AC患者。对比观察既往有治疗患者(既往治疗组，n＝245)与既往无治疗患者(既往未治疗组，n＝604)的POEM疗效差异，并分析出现围手术期严重并发症、术后临床反流和临床治疗失败的风险因素。结果:两组共34例(4.0%，34/849)患者出现气胸、胸腔积液、延迟出血等围手术期严重并发症，但2组间发生率差异无统计学意义[4.5%(11/245)比3.8%(23/604), n χ2＝0.21，n P＝0.65]。多因素Logistic回归分析发现手术持续时间≥60 min(n OR＝3.82，95%n CI：1.81～8.08，n P100例(n OR＝0.23，95%n CI：0.07～0.76，n P<0.05)是避免发生围手术期严重并发症的独立保护因素。23个月(1～71个月)的中位随访期间，有203例(23.9%，203/849)出现临床反流，有94例(11.1%，94/849)临床治疗失败。既往治疗组的临床反流率为26.9%(66/245)，既往未治疗组为22.7%(137/604)，2组间差异无统计学意义(n P＝0.19)。多因素Logistic回归分析发现全层肌切开术(n OR＝1.49，95%n CI：0.98～2.29，n P＝0.07)是随访期间发生临床反流的独立危险因素。既往治疗组POEM术后5年临床治疗失败率为18.0%(44/245)，既往未治疗组为8.3%(50/604)，2组间差异有统计学意义(n P<0.05)。多因素Cox回归分析发现病程≥10年(n HR＝1.62，95%n CI：1.04～2.52，n P＝0.03)、有既往治疗(n HR＝1.90，95%n CI：1.26～2.88，n P<0.05)是随访期间临床治疗失败的独立危险因素。n 结论:POEM具有较低的围手术期严重并发症发生率，并且具有较好的中长期疗效，对于AC治疗失败的患者POEM仍可作为一种安全有效的补救治疗方法。虽然既往治疗不会明显增加围手术期严重并发症和临床反流的发生，但是会显著增加POEM临床治疗失败的发生。“,”Objective:To evaluate the effect of peroral endoscopic myotomy (POEM) on perioperative and follow-up outcomes of achalasia patients undergoing unsuccessful prior treatment.Methods:A retrospective analysis was performed on 849 patients with achalasia who underwent POEM and completed follow-up at endoscopy center, Zhongshan Hospital, Fudan University, from August 2010 to December 2014. The effect of POEM was compared between patients with prior treatment (n=245) and those without (n=604). Risk factors for perioperative major adverse events, postoperative clinical reflux and failure were analyzed.Results:A total of 34 patients (4.0%, 34/849) experienced major adverse events, such as pneumothorax, hydrothorax, delayed bleeding. No statistical difference in major adverse events was found between the two groups [4.5% (11/245) VS 3.8% (23/604), n χ2=0.21, n P=0.65]. Multivariate logistic regression analysis demonstrated that procedure duration ≥60 min was the independent risk factor for perioperative major adverse events (n OR=3.82, 95%n CI: 1.81-8.08, n P100 cases was the independent protective factor for major adverse events (n OR=0.23, 95%n CI: 0.07-0.76, n P<0.05). During a median follow-up of 23 months (ranging 1-71 months), clinical reflux occurred in 203 patients (23.9%, 203/849), and clinical failure occurred in 94 patients (11.1%, 94/849). Patients with prior treatment had a clinical reflux rate of 26.9% (66/245), which was comparable with those without (22.7%, 137/604) (n P=0.19). Multivariate logistic regression analysis demonstrated that Heller myotomy was the independent risk factor for clinical reflux (n OR=1.49, 95%n CI: 0.98-2.29, n P=0.07). Clinical failure rate in patients with prior treatment at 5 years after POEM was 18.0% (44/245), and that in those without was 8.3% (50/604) (n P<0.05). Multivariate cox analysis revealed that disease duration ≥10 years (n HR=1.62, 95%n CI: 1.04-2.52, n P=0.03) and prior treatment (n HR=1.90, 95%n CI: 1.26-2.88, n P<0.05) were independent risk factors for clinical failure.n Conclusion:POEM is an effective and safe rescue for patients who underwent unsuccessful prior treatment, with a low rate of perioperative major adverse events and good long-term effects. Prior treatment may increase the risk for clinical failure of POEM, it may not significantly increase severe perioperative complications or clinical reflux though.