BACKGROUND Short-term outcomes of laparoscopic Heller myotomy (LHM) for achalasia have been excellent, although the long-term durability of this operation remains to be established. The aim of this study was to evaluate the long-term outcomes of LHM. METHODS A single-institution review of patients undergoing LHM between 1992 and 2003 with > or =5 years follow-up. Failure was defined as symptom recurrence requiring reoperation. Univariate and multiple regression analysis were performed to identify preoperative variables predictive of long-term success. RESULTS A total of 46 patients underwent LHM with Toupet (n = 42) or Dor (n = 4) fundoplication. At a mean follow-up of 6.4 years, 37 (80%) patients remained free from failure. Mean time to symptom recurrence in those failing LHM was 21.3 months (range, 0.5-77). Causes of failure included nonfunctioning end-stage esophagus (n = 4), fibrotic narrowing at the gastroesophageal junction (n = 4), and tight wrap (n = 1). Univariate analysis identified high preoperative lower esophageal sphincter pressure (LESP), no prior therapy, short duration of symptoms, and absence of sigmoidal esophagus as predictors of long-term success (P < or = .044 each). High LESP remained the only predictor of long-term durability in multiple regression analysis (P = .043). Reoperations included redo myotomy (n = 2), esophagectomy (n = 6), or both (n = 1). At final follow-up, 44 (96%) patients reported significant symptom improvement compared with pre-LHM severity. CONCLUSIONS LHM is associated with an 80% long-term success rate. Successful LHM may be predicted by high LESP, no prior therapy, short symptom duration, or absence of sigmoidal esophagus. In this series, failures of LHM underwent reoperation (redo myotomy or esophagectomy) with good results.