Jackhammer esophagus with and without esophagogastric junction outflow obstruction demonstrates altered neural control resembling type 3 achalasia

Background: Esophageal hypercontractility can manifest with and without esophagogastric junction (EGJ) outflow obstruction. We investigated clinical presentations and motility patterns in patients with esophageal hypercontractile disorders. Methods: Esophageal HRM studies fulfilling Chicago Classification 3.0 criteria for jackhammer esophagus (distal contractile integral, DCI >8000mmHg.cm.s in≥20% swallows) with (n=30) and without (n=83) EGJ obstruction (integrated relaxation pressure, IRP>15mmHg) were retrospectively reviewed from five centers (4 in Europe, 1 in US). Single swallows (SS) and multiple rapid swallows (MRS) were analyzed using HRM software tools (IRP, DCI, distal latency, DL); MRS: SS DCI ratio >1 defined contraction reserve. Comparison groups were achalasia type 3 (n=72, positive control for abnormal inhibition and EGJ obstruction) and healthy controls (n=18). Symptoms, HRM metrics, and MRS contraction reserve were analyzed within jackhammer subgroups and comparison groups. Key Results: The esophageal smooth muscle was excessively stimulated at baseline in jackhammer subgroups, with lack of augmentation following MRS identified more often compared with controls (P=.003) and type 3 achalasia (P=.07). Consistently abnormal inhibition was identified in type 3 achalasia (47%), and to a lower extent in jackhammer with obstruction (37%, P=.33), jackhammer esophagus (28%, P=.01), and controls (11%, P&nbsp