Evaluation of outcome after cardiomyotomy for achalasia using the Chicago classification

Background: Achalasia can be subdivided into manometric subtypes according to the Chicago classification. These subtypes are proposed to predict outcome after treatment. This hypothesis was tested using a database of patients who underwent laparoscopic Heller's cardiomyotomy with anterior fundoplication.

Methods: All patients who underwent Heller's cardiomyotomy for achalasia between June 1993 and March 2015 were identified from an institutional database. Manometry tracings were retrieved and re-reported according the Chicago classification. Outcome was assessed by a postal questionnaire, and designated a success if the modified Eckardt score was 3 or less, and the patient had not undergone subsequent surgery or pneumatic dilatation. Difference in outcome after cardiomyotomy was analysed with a mixed-effects logistic regression model.

Results: Sixty, 111 and 24 patients had type I, II and II achalasia respectively. Patients with type III achalasia were more likely to be older than those with type I or II (mean age 63 versus 50 and 49 years respectively; P = 0·001). Some 176 of 195 patients returned questionnaires after surgery. Type III achalasia was less likely to have a successful outcome than type II (odds ratio (OR) 0·38, 95 per cent c.i. 0·15 to 0·94; P = 0·035). There was no significant difference in outcome between types I and II achalasia (II versus I: OR 0·87, 0·47 to 1·60; P 0·663). The success rate at 3-year follow-up was 69 per cent (22 of 32) for type I, 66 per cent (33 of 50) for type II and 31 per cent (4 of 13) for type III.

Conclusion: Type III achalasia is a predictor of poor outcome after cardiomyotomy. There was no difference in outcome between types I and II achalasia.