BACKGROUND: Jackhammer esophagus is an hypercontractile esophageal disorder recently brought to light with the advent of high resolution manometry (HRM). As Jackhammer esophagus is purely a manometric diagnosis, little is known about its clinical expression. AIMS: We hypothesized that the extreme esophageal contractions encountered in this disease cause upper digestive symptoms such as dysphagia and chest pain. Thus, the aim of our study was to identify the clinical characteristics associated with this new motility disorder. METHODS: A retrospective observational study was conducted from January 2015 to September 2017 at the CHUM gastro-intestinal motility center. Among all the HRM performed, patients with a diagnosis of jackhammer esophagus were included. This diagnosis is made when at least 20% of the swallows being studied are hypercontractile, with a distal contractile integral (DCI) of >8000 mmHg.s.cm (Chicago classification). Each patient’s chart was reviewed to collect clinical data: age, sex, comorbidities, proton pump inhibitor use, along with manometry, upper digestive endoscopy, biopsies, pH-monitoring and barium swallow results. RESULTS: Among the 1046 HRM done during the study period, 34 patients with jackhammer esophagus were included (mean age 62 ± 13 years, 88% females). Their main symptoms were dysphagia (71%), pyrosis (44%), retrosternal chest pain (38%) and epigastralgia (32%). In half of the patients, at least 50% of swallows were hypercontractile. The mean DCI of the hypercontractile esophageal contractions was 11 600 ± 3600 mmHg.s.cm. Other HRM findings were hypertonia (26%) and/or inadequate relaxation (29%) of the lower esophageal sphincter. Upper digestive endoscopy results were available for 26 patients: 18 normal, 3 hiatal hernias, 2 esophageal dilatations, 2 lower esophageal sphincter hypertonia impressions and one with longitudinal striae. Among the 12 available biopsy results, 2 were abnormal: one lymphocytic exostosis and one esophagitis without eosinophilia. Pathological gastro-esophageal reflux was found in 3 of the 9 patients investigated with pH-monitoring. Among the 8 patients who had a barium swallow, 4 had a normal study, 3 had spastic contractions of the esophagus and one had an incomplete relaxation of the cricopharyngeal muscle. CONCLUSIONS: Jackhammer esophagus was diagnosed in 3% of the patients referred for a HRM to our gastro-intestinal motility center. A strong female predominance is found in this study. In more than two thirds of cases, the clinical presentation of jackhammer esophagus is dysphagia. Malfunctioning of the lower esophageal sphincter can be demonstrated during manometry. Upper digestive endoscopy and biopsies seem unhelpful in suspecting the diagnosis before HRM is performed. FUNDING AGENCIES: None