暂时性自膨胀贲门支架治疗犬贲门失弛缓症模型的实验研究

Temporary self-expanding cardia stents for the treatment of achalasia:an experimental study in dogs

目的评价应用暂时性可回收贲门覆膜支架(TRC-CS)治疗犬贲门失迟缓症模型的有效性并探讨理想的回收时间。方法 84条贲门失弛缓症模型犬随机分为7组(每组12条):对照组(CG;无支架置入)、标准支架置入组(NSCG;标准食管支架)和5组治疗组(TGs)置入(TRC-CS)。NSCG支架置入后4 d取出,5组TGs支架分别在4 d(4 d-TG)、2周(2 w-TG)、1个月(1 m-TG)、3个月(3 m-TG)和6个月(6m-TG)取出。支架置入前、支架取出后和1周,1、3和6个月随访时分别行食管下段括约肌压力(LESP)测试和时间-钡餐检查进行疗效评价。NSCG和4 d-TG组在每个随访点各处死3条犬行组织病理学检查评价支架置入后的炎症反应。结果支架置入和取出以及随访过程中所有犬均能很好耐受。在6个月随访结束时,2 w-TG和1 m-TG组表现出较低的支架移位率(n=2),而NSCG和3 m-TG组各有4只犬支架移位,6 m-TG组有6只犬支架移位。与建模后相比,2 w-TG和1m-TG组的LESP(P<0.05)和钡餐高度(P=0.014 4和0.040 9)都有明显的改善。增殖细胞核抗原(PCNA)和抗α-平滑肌动蛋白抗原免疫组化染色提示NSCG和4 d-TG组在各不同随访点的炎症反应没有明显差异。结论 TRC-CS置入可以有效治疗犬贲门失迟缓症模型。LESP和时间-钡餐检查提示理想的支架回收时间在2周～1个月。

Objective To assess the performance,efficiency and optimal removal time of a newly designed temporary retrievable cardia covered stent（TRC-CS） for the treatment of achalasia in a dog model.Methods Eighty-four achalasia-like dog models were randomly divided into seven groups of 12,a control group（CG;no stent insertion）,a standard stent control group（NSCG,standard esophageal stent） and five treatment groups（TG,TRC-CS）.Stents were retrieved at 4 days after insertion in the NSCG and at 4 days（4d-TG）,2 weeks（2w-TG）,1 month（1m-TG）,3 months（3m-TG）,and 6 months（6m-TG） in the TGs.lower esophageal sphincter pressure（LESP） and a timed barium esophagram were assessed before stent insertion,after stent retrieval,and at 1-week,1-,3-and 6-month follow-up.Three dogs in NSCG and 4d-TG were sacrificed for histological examination at each follow-up to investigate the inflammatory reaction after stent insertion.Results Stent insertion/removal and the follow-up procedures were well tolerated.At 6-month follow-up,the 2w-TG and 1m-TG demonstrated an acceptable stent migration（n = 2 in both TGs versus n = 4 in NSCG,n = 4 in 3m-TG,and n = 6 in 6m-TG）,improved LESP compared to after BAC injection（P 0.05）,and improved timed barium height（P = 0.014 4 and 0.040 9）.Mouse-proliferating cell nuclear antigen（PCNA）and α-smooth muscle actin staining revealed no inflam-matory reaction difference between the NSCG and 4d-TG at each follow-up.Conclusions the TRC-CS was effective in the treatment of achalasia in a dog model.LESP measurements,timed barium esophagram studies suggest an optimal stent retrieval time of between 2 w ～ 1 m.