A Unique Esophageal Motor Pattern That Involves Longitudinal Muscles Is Responsible for Emptying in Achalasia Esophagus
ABSTRACT Achalasia esophagus is characterized by loss of peristalsis and incomplete esophagogastric junction (EGJ) relaxation. We studied mechanisms of esophageal emptying in patients with achalasia using simultaneous high-resolution manometry, multiple intraluminal impedance, and high-frequency intraluminal ultrasonography image recordings.
Achalasia was categorized into 3 subtypes, based on the esophageal response to swallows: types 1 and 2 were defined by simultaneous pressure waves of <30 mm Hg and >30 mm Hg, respectively, and type 3 was defined by spastic simultaneous esophageal contractions.
Based on high-resolution manometry, the predominant achalasia pattern of type 2 was characterized by a unique motor pattern that consisted of upper esophageal sphincter contraction, simultaneous esophageal pressure (pan-esophageal pressurization), and EGJ contraction following swallows. High-frequency intraluminal ultrasonography identified longitudinal muscle contraction of the distal esophagus as the cause of pan-esophageal pressurization in type 2 achalasia. Multiple intraluminal impedance revealed that esophageal emptying occurred intermittently (36% swallows) during periods of pan-esophageal pressurization. Patients with achalasia of types 1 and 3 had no emptying or relatively normal emptying during most swallows, respectively.
In achalasia, esophageal emptying results from swallow-induced longitudinal muscle contraction of the distal esophagus, which increases esophageal pressure and allows flow across the nonrelaxed EGJ.
[Show abstract] [Hide abstract]
ABSTRACT: Background Esophageal motor disorders are a heterogeneous group of conditions identified by esophageal manometry that lead to esophageal dysfunction. The aim of this study was to assess the clinical utility of endoscopic ultrasound (EUS) in the further evaluation of patients with esophageal motor disorders categorized using the updated Chicago Classification.Methods We performed a retrospective, single center study of 62 patients with esophageal motor disorders categorized according to the Chicago Classification. All patients underwent standard radial endosonography to assess for extra-esophageal findings or alternative explanations for esophageal outflow obstruction. Secondary outcomes included esophageal wall thickness among the different patient subsets within the Chicago Classification.Key ResultsEUS identified 9/62 (15%) clinically relevant findings that altered patient management and explained the etiology of esophageal outflow obstruction. We further identified substantial variability in esophageal wall thickness in a proportion of patients including some with a significantly thickened non-muscular layer.Conclusions & InferencesEUS findings are clinically relevant in a significant number of patients with motor disorders and can alter clinical management. Variability in esophageal wall thickness of the muscularis propria and non-muscular layers identified by EUS may also explain the observed variability in response to standard therapies for achalasia.Neurogastroenterology and Motility 08/2014; 26(8). DOI:10.1111/nmo.12379 · 2.94 Impact Factor
Article: Esophageal Function TestingGastrointestinal Endoscopy Clinics of North America 10/2014; 24(4):667-685. DOI:10.1016/j.giec.2014.06.006
[Show abstract] [Hide abstract]
ABSTRACT: Achalasia is a primary neurodegenerative disorder of the esophagus characterized by loss of function of the lower esophageal sphincter (LES) and of esophageal peristalsis, which causes symptoms such as dysphagia, regurgitation, weight loss, and chest pain. Esophageal manometry is the gold standard for the diagnosis of achalasia. The typical manometric features are incomplete relaxation of a frequently hypertensive LES and lack of peristalsis in the tubular esophagus. High-resolution manometry using catheters with 36 solid-state sensors spaced 1cm apart has more and more replaced water-perfused and pull-through manometry. However, the main innovation of this method is the conversion of pressure data into a topographical plot. The data can be modified using interpolation to generate high-resolution esophageal pressure topography (HREPT). HREPT is more sensitive, provides more detailed information, and is easier to perform than conventional manometry. Introduction of HREPT had an impact especially on the diagnosis and management of achalasia. A clinically relevant impact was achieved by the identification of 3 clinical subtypes which seem to predict treatment outcomes. This review analyzes the progress made in the diagnosis and management of achalasia since the recent introduction of HREPT.