Application of the newly developed stents in the treatment of benign cardia stricture: an experimental comparative study.

Abstract

BACKGROUND: Retrievable temporary stent placement has recently been suggested as a potential treatment for benign esophageal stricture. OBJECTIVE: To assess the efficacy of a newly designed cardia stent for the treatment of benign cardia stricture in a canine model compared with groups that received pneumatic dilation or standard esophageal stent insertion. DESIGN: Basic experimental study. SETTING: GI interventional center. PATIENTS: Forty-eight dog models were randomly divided into a control group (no stent insertion) (n=12), a pneumatic dilation group (PDG) (n=12), a standard esophageal stent group (SESG) (n=12), and a novel cardia stent group (NCSG) (n=12). INTERVENTIONS: Pneumatic dilation, standard esophagus stent, cardia stent. MAIN OUTCOME MEASUREMENTS: Lower esophageal sphincter pressures and the 5-minute barium height were assessed before and immediately after the procedure, after 1 week, and at 1-, 3-, and 6-month follow-up. Three dogs in each group were killed for histological examination. RESULTS: Stent insertion was tolerated by all dogs, with a lower migration rate in the NCSG (0% vs 41.7% in the SESG; P=.0373). At the 6-month follow-up, the lower esophageal sphincter pressure and 5-minute barium height values in the NCSG were still stable compared with those in the PDG and SESG (P<.05). Immunohistochemistry for mouse anti-proliferating cell nuclear antigen and &#x3b1;-smooth muscle actin revealed a stronger inflammatory reaction peak in the PDG than in the SESG and NCSG (P<.05). Collagen proliferation was most severe after 6 months in the PDG (P<.05). LIMITATIONS: Longer follow-up studies are required to assess whether the recurrence rate is lower because of less inflammation and scarring. CONCLUSIONS: The novel cardia stent was more effective than pneumatic dilation or a standard stent in this canine model.