Clinical Review & Education
Review
Achalasia A Systematic Review John E. Pandolfino, MD, MSCI; Andrew J. Gawron, MD, PhD, MS
IMPORTANCE Achalasia significantly affects patients’ quality of life and can be difficult to
Author Audio Interview at jama.com
diagnose and treat.
JAMAPatient Page page 1876
OBJECTIVE To review the diagnosis and management of achalasia, with a focus on phenotypic
Supplemental content at jama.com
classification pertinent to therapeutic outcomes. EVIDENCE REVIEW Literature review and MEDLINE search of articles from January 2004 to
February 2015. A total of 93 articles were included in the final literature review addressing facets of achalasia epidemiology, pathophysiology, diagnosis, treatment, and outcomes. Nine randomized controlled trials focusing on endoscopic or surgical therapy for achalasia were included (734 total patients). FINDINGS A diagnosis of achalasia should be considered when patients present with dysphagia, chest pain, and refractory reflux symptoms after an endoscopy does not reveal a mechanical obstruction or an inflammatory cause of esophageal symptoms. Manometry should be performed if achalasia is suspected. Randomized controlled trials support treatments focused on disrupting the lower esophageal sphincter with pneumatic dilation (70%-90% effective) or laparoscopic myotomy (88%-95% effective). Patients with achalasia have a variable prognosis after endoscopic or surgical myotomy based on subtypes, with type II (absent peristalsis with abnormal pan-esophageal high-pressure patterns) having a very favorable outcome (96%) and type I (absent peristalsis without abnormal pressure) having an intermediate prognosis (81%) that is inversely associated with the degree of esophageal dilatation. In contrast, type III (absent peristalsis with distal esophageal spastic contractions) is a spastic variant with less favorable outcomes (66%) after treatment of the lower esophageal sphincter. CONCLUSIONS AND RELEVANCE Achalasia should be considered when dysphagia is present and not explained by an obstruction or inflammatory process. Responses to treatment vary based on which achalasia subtype is present. JAMA. 2015;313(18):1841-1852. doi:10.1001/jama.2015.2996
T
he constellation of dysphagia (difficulty swallowing), chest pain, and reflux symptoms may be caused by a variety of diseases of the esophagus such as gastroesophageal reflux disease, malignancy, mechanical obstruction (strictures, rings, or diverticula), and achalasia and other motility disorders. Achalasia is derived from the Greek khalasis, translated as “not loosening or relaxing.” A common historical definition of achalasia is the inability of the lower esophageal sphincter to relax in the setting of absent peristalsis. An initial trial of acid suppression (6-8 weeks) is reasonable, but when dysphagia symptoms persist or are dominated by the report of dysphagia, endoscopy should be performed to evaluate for mechanical obstruction or inflammatory processes. When these are not found, achalasia should be considered, especially in the setting of dysphagia primarily to liquids. Liquids can pool and accumulate above a tight, “unrelaxing” lower esophageal jama.com
CME Quiz at jamanetworkcme.com and CME Questions page 1859
Author Affiliations: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois (Pandolfino); Division of Gastroenterology, Hepatology, and Nutrition, University of Utah, Salt Lake City (Gawron). Corresponding Author: John E. Pandolfino, MD, MSCI, Division of Gastroenterology and Hepatology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 676 N St Clair St, Ste 1409, Chicago, IL 60611 (j-pandolfino @northwestern.edu). Section Editor: Mary McGrae McDermott, MD, Senior Editor.
sphincter, whereas they are usually less of an issue in the setting of structural causes of dysphagia. Recent advances in diagnostic testing for achalasia, especially high-resolution esophageal manometry, have provided new insights into the pathogenesis and clinical manifestation of this disorder. The purpose of this review is to highlight the epidemiology, pathogenesis, and clinical approach to patients with achalasia, emphasizing published evidence pertinent to both primary care clinicians and specialist physicians.
Evidence Acquisition and Synthesis The literature was reviewed based on an initial broad MEDLINE search using the terms ((((esophageal motility) OR achalasia) OR high (Reprinted) JAMA May 12, 2015 Volume 313, Number 18
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
1841
Clinical Review & Education Review
Achalasia
Figure 1. Anatomy and Innervation of the Esophagus A Anatomy of the esophagus
and relationship to adjacent structures
C
Cricoid cartilage Upper esophageal sphincter (UES)
Esophageal wall Myenteric plexus ganglion with postganglionic neurons
Longitudinal muscle (reflected) Striated muscle
Myenteric plexus Circular muscle
Transition zone
Esophageal plexus Adventitia
Esophagus Smooth muscle Diaphragm (cut) Lower esophageal sphincter (LES)
B
Muscularis propria
Esophagogastric junction Submucosal plexus
Stomach ESOPHAGUS
Stratified squamous epithelium
Level of section
Circular muscle
Submucosa
Muscularis mucosa
Mucosa
Lumen
Longitudinal muscle Crural diaphragm
Esophagogastric junction LES Crural diaphragm Proximal gastric cardia LES
STOMACH
resolution manometry) OR Chicago classification) OR esophageal peristalsis. Articles published from January 2004 to February 2015 in English were included. This search yielded 6194 references, of which 5788 were in English. Case reports (n = 521) and review articles (n = 899) were excluded. Articles were further searched using terms specific for epidemiology, genetics, diagnosis, manometry, surgery, pneumatic dilation, botulinum toxin, and per-oral endoscopic myotomy. Other pertinent articles and guidelines were obtained through citations or were known to the authors. We reviewed titles and abstracts to determine relevance to the article sections and ultimately included 93 articles in the review (n = 4276 excluded). A total of 9 randomized controlled trials were included when evaluating endoscopic and surgical treatment modalities (comprising 734 total patients). Details are shown in the eFigure in the Supplement.
Structure and Normal Function of the Esophagus The esophagus is an 18- to 26-cm muscular hollow tube that transports food from the oropharynx into the stomach (Figure 1). There are 4 primary layers of esophageal tissue—the mucosa, sub1842
mucosa, muscularis propria, and adventitia. The esophagus originates at the level of the cricoid cartilage and normally terminates below the hiatus in the right crura of the diaphragm. The muscularis propria gradually changes from predominant skeletal muscle in the upper esophagus to predominantly smooth muscle in the distal esophagus, with mixing of muscle types along the length of the esophagus (Figure 1). Both circular and longitudinal muscle layers are present, and within the diaphragmatic hiatus there exists a 2- to 4-cm thickened circular muscle layer, the lower esophageal sphincter. Esophageal innervation consists of both parasympathetic and sympathetic nerves, with peristalsis regulated via the parasympathetic pathway from the vagus nerve and the intrinsic enteric nervous system. Despite the seemingly simple task of food transport, the mechanism and control of esophageal function is complex, largely owing to the neural coordination required with the oropharynx and transition through different anatomical domains with mixed muscle types. Once a food or liquid bolus enters the esophagus, primary peristalsis strips the food bolus down the length of the esophagus. Peristaltic contraction in the striated muscle esophagus is dependent on central mechanisms that involve sequential activation of excitatory activity of lower motor neurons in the vagal nucleus am-
JAMA May 12, 2015 Volume 313, Number 18 (Reprinted)
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
jama.com
Achalasia
Review Clinical Review & Education
Figure 2. Neural Control of Esophageal Motility and Plot From High-Resolution Esophageal Manometry, With Anatomical Correlates A Parasympathetic esophageal innervation
B Esophageal pressure topography (EPT) plot from high
C Anatomical correlation with EPT plot
resolution manometry (normal study) POSTERIOR
ANTERIOR
0 Dorsal motor nucleus of vagus Rostral Caudal
30
Color pressure scale, mm Hg 60 90 120 150
180
PONS
Esophagus
Cricoid cartilage
Nucleus ambiguus
Vagus nerve
UES Striated muscle
Cervical esophagus
Transition zone
Thoracic esophagus Smooth muscle
Striated muscle innervation Parasympathetic efferent Neuromuscular junction Smooth muscle innervation Preganglionic excitatory neuron Preganglionic inhibitory neuron Postganglionic excitatory neuron cell body Postganglionic inhibitory neuron cell body
Diaphragm (cut) LES
Abdominal esophagus
UES
LES
0
3 Swallow
6
9
12
Time, s
Schematic representation of esophageal motor activity during a swallow A, The esophagus is controlled by both centrally mediated and peripheral intrinsic processes that are compartmentalized based on location in the esophagus and muscle type. B, Output from high-resolution manometry, displayed as esophageal pressure topography (Clouse plot), showing esophageal pressures over time after a single swallow. The x-axis indicates time; the y-axis indicates location from the oropharynx to the stomach, as shown in panel C. Pressure is displayed on a color scale instead of the conventional tracings; thus, a seamless dynamic representation of motor activity is displayed
that provides anatomical representation of the pressure profile. The striated muscle esophagus can be distinguished from the smooth muscle esophagus, as there is a pressure gap at the transition zone that demarcates the introduction of smooth muscle activity. The sphincters are distinguished by the 2 areas of high pressure between the striated and smooth muscle esophagus. LES indicates lower esophageal sphincter; UES, upper esophageal sphincter. Esophageal pressure topography plot reproduced with permission from the Esophageal Center at Northwestern Medicine.
biguus (Figure 2).1 This promotes peristaltic propagation through a sequenced top-to-bottom excitation mediated by release of acetylcholine at the motor end plates (Figure 2).1 Primary peristalsis in esophageal smooth muscle is preceded by inhibition, which stops a progressing peristaltic wave when another swallow is initiated.2,3 This involves patterned activation of preganglionic neurons in the dorsal motor nucleus of the vagus that project onto inhibitory and excitatory neurons in the esophageal myenteric plexus (Figure 2). Under normal circumstances, the inhibitory pathway is activated first to relax the esophagus to promote filling and transport through the esophagus. The inhibitory neu-
rons activated by the preganglionic neurons from the caudal dorsal motor neuron release nitric oxide to promote deglutitive inhibition. This is followed by sequential activation of excitatory neurons, which releases acetylcholine in response to activation by preganglionic neurons arising from the rostral dorsal motor nucleus. The direction and rate of propagation is modulated by the increasing inhibitory influence in the distal esophagus, called the latency gradient.2,3 This essentially delays contractions in the distal esophagus and allows propagation to proceed in an aboral direction. Secondary peristalsis related to distention of the esophagus will elicit a local reflex independent of the vagal input from the dorsal
jama.com
(Reprinted) JAMA May 12, 2015 Volume 313, Number 18
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
1843
Clinical Review & Education Review
Achalasia
Box. Symptoms Suggestive of Achalasia That May Prompt Referral for Esophageal Motility Testinga Esophageal Symptoms
Dysphagia (90% of patients) Heartburn (75% of patients) Regurgitation or vomiting (45% of patients) Noncardiac chest pain (20% of patients) Epigastric pain (15% of patients) Odynophagia (50% of swallows are effective without criteria for spasm or jackhammer esophagus
Yes
Modified from Kahrilas et al.50 Classification algorithm based on results of high-resolution manometry with ten 5-mL water swallows. Note that achalasia should be considered in patients presenting with esophagogastric junction outflow obstruction and absent contractility. Failed peristalsis denotes swallows with a distal contractile integral (DCI) less than 100 mm Hg·sec·cm (the DCI quantifies the distal contractile pressure exceeding 20 mm Hg from the transition zone to the proximal aspect of the lower esophageal sphincter [LES] [amplitude × time × length in units of mm Hg·sec·cm]).Panesophageal pressurization denotes uniform pressurization greater than 30 mm Hg extending from the upper esophageal sphincter to the esophagogastric junction. Contractile vigor denotes the strength of distal contraction as defined
topic concluded that using modern technique the risk was less than 1%, comparable to the risk of unrecognized perforation during Heller myotomy.69 Pneumatic dilation should be performed by experienced physicians, and surgical backup is required. Studies using pneumatic dilation as the initial treatment of achalasia have reported excellent long-term symptom control. A third of patients will relapse in 4 to 6 years and may require repeat dilation. Response to therapy may be related to preprocedural clinical parameters, such as age (favorable if >45 years), sex (more favorable among females than males),70 esophageal diameter (inversely related to response), and achalasia subtype (type II better than I and III).52,71 Although surgical myotomy has a greater response rate than a single pneumatic dilation, it appears that a series of dilations is a reasonable alternative to surgery. A recent randomized trial compared this type of graded strategy with surgical myotomy and found it to be noninferior in efficacy (Table 3).55 Addition of botulinum toxin injection does not appear to improve outcomes.62 1848
Normal esophageal motor function a
by the DCI. Ineffective esophageal motility (IEM) is diagnosed when a patient exhibits greater than 50% ineffective swallows (ineffective swallows are either failed [DCI
Review
Achalasia A Systematic Review John E. Pandolfino, MD, MSCI; Andrew J. Gawron, MD, PhD, MS
IMPORTANCE Achalasia significantly affects patients’ quality of life and can be difficult to
Author Audio Interview at jama.com
diagnose and treat.
JAMAPatient Page page 1876
OBJECTIVE To review the diagnosis and management of achalasia, with a focus on phenotypic
Supplemental content at jama.com
classification pertinent to therapeutic outcomes. EVIDENCE REVIEW Literature review and MEDLINE search of articles from January 2004 to
February 2015. A total of 93 articles were included in the final literature review addressing facets of achalasia epidemiology, pathophysiology, diagnosis, treatment, and outcomes. Nine randomized controlled trials focusing on endoscopic or surgical therapy for achalasia were included (734 total patients). FINDINGS A diagnosis of achalasia should be considered when patients present with dysphagia, chest pain, and refractory reflux symptoms after an endoscopy does not reveal a mechanical obstruction or an inflammatory cause of esophageal symptoms. Manometry should be performed if achalasia is suspected. Randomized controlled trials support treatments focused on disrupting the lower esophageal sphincter with pneumatic dilation (70%-90% effective) or laparoscopic myotomy (88%-95% effective). Patients with achalasia have a variable prognosis after endoscopic or surgical myotomy based on subtypes, with type II (absent peristalsis with abnormal pan-esophageal high-pressure patterns) having a very favorable outcome (96%) and type I (absent peristalsis without abnormal pressure) having an intermediate prognosis (81%) that is inversely associated with the degree of esophageal dilatation. In contrast, type III (absent peristalsis with distal esophageal spastic contractions) is a spastic variant with less favorable outcomes (66%) after treatment of the lower esophageal sphincter. CONCLUSIONS AND RELEVANCE Achalasia should be considered when dysphagia is present and not explained by an obstruction or inflammatory process. Responses to treatment vary based on which achalasia subtype is present. JAMA. 2015;313(18):1841-1852. doi:10.1001/jama.2015.2996
T
he constellation of dysphagia (difficulty swallowing), chest pain, and reflux symptoms may be caused by a variety of diseases of the esophagus such as gastroesophageal reflux disease, malignancy, mechanical obstruction (strictures, rings, or diverticula), and achalasia and other motility disorders. Achalasia is derived from the Greek khalasis, translated as “not loosening or relaxing.” A common historical definition of achalasia is the inability of the lower esophageal sphincter to relax in the setting of absent peristalsis. An initial trial of acid suppression (6-8 weeks) is reasonable, but when dysphagia symptoms persist or are dominated by the report of dysphagia, endoscopy should be performed to evaluate for mechanical obstruction or inflammatory processes. When these are not found, achalasia should be considered, especially in the setting of dysphagia primarily to liquids. Liquids can pool and accumulate above a tight, “unrelaxing” lower esophageal jama.com
CME Quiz at jamanetworkcme.com and CME Questions page 1859
Author Affiliations: Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois (Pandolfino); Division of Gastroenterology, Hepatology, and Nutrition, University of Utah, Salt Lake City (Gawron). Corresponding Author: John E. Pandolfino, MD, MSCI, Division of Gastroenterology and Hepatology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 676 N St Clair St, Ste 1409, Chicago, IL 60611 (j-pandolfino @northwestern.edu). Section Editor: Mary McGrae McDermott, MD, Senior Editor.
sphincter, whereas they are usually less of an issue in the setting of structural causes of dysphagia. Recent advances in diagnostic testing for achalasia, especially high-resolution esophageal manometry, have provided new insights into the pathogenesis and clinical manifestation of this disorder. The purpose of this review is to highlight the epidemiology, pathogenesis, and clinical approach to patients with achalasia, emphasizing published evidence pertinent to both primary care clinicians and specialist physicians.
Evidence Acquisition and Synthesis The literature was reviewed based on an initial broad MEDLINE search using the terms ((((esophageal motility) OR achalasia) OR high (Reprinted) JAMA May 12, 2015 Volume 313, Number 18
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
1841
Clinical Review & Education Review
Achalasia
Figure 1. Anatomy and Innervation of the Esophagus A Anatomy of the esophagus
and relationship to adjacent structures
C
Cricoid cartilage Upper esophageal sphincter (UES)
Esophageal wall Myenteric plexus ganglion with postganglionic neurons
Longitudinal muscle (reflected) Striated muscle
Myenteric plexus Circular muscle
Transition zone
Esophageal plexus Adventitia
Esophagus Smooth muscle Diaphragm (cut) Lower esophageal sphincter (LES)
B
Muscularis propria
Esophagogastric junction Submucosal plexus
Stomach ESOPHAGUS
Stratified squamous epithelium
Level of section
Circular muscle
Submucosa
Muscularis mucosa
Mucosa
Lumen
Longitudinal muscle Crural diaphragm
Esophagogastric junction LES Crural diaphragm Proximal gastric cardia LES
STOMACH
resolution manometry) OR Chicago classification) OR esophageal peristalsis. Articles published from January 2004 to February 2015 in English were included. This search yielded 6194 references, of which 5788 were in English. Case reports (n = 521) and review articles (n = 899) were excluded. Articles were further searched using terms specific for epidemiology, genetics, diagnosis, manometry, surgery, pneumatic dilation, botulinum toxin, and per-oral endoscopic myotomy. Other pertinent articles and guidelines were obtained through citations or were known to the authors. We reviewed titles and abstracts to determine relevance to the article sections and ultimately included 93 articles in the review (n = 4276 excluded). A total of 9 randomized controlled trials were included when evaluating endoscopic and surgical treatment modalities (comprising 734 total patients). Details are shown in the eFigure in the Supplement.
Structure and Normal Function of the Esophagus The esophagus is an 18- to 26-cm muscular hollow tube that transports food from the oropharynx into the stomach (Figure 1). There are 4 primary layers of esophageal tissue—the mucosa, sub1842
mucosa, muscularis propria, and adventitia. The esophagus originates at the level of the cricoid cartilage and normally terminates below the hiatus in the right crura of the diaphragm. The muscularis propria gradually changes from predominant skeletal muscle in the upper esophagus to predominantly smooth muscle in the distal esophagus, with mixing of muscle types along the length of the esophagus (Figure 1). Both circular and longitudinal muscle layers are present, and within the diaphragmatic hiatus there exists a 2- to 4-cm thickened circular muscle layer, the lower esophageal sphincter. Esophageal innervation consists of both parasympathetic and sympathetic nerves, with peristalsis regulated via the parasympathetic pathway from the vagus nerve and the intrinsic enteric nervous system. Despite the seemingly simple task of food transport, the mechanism and control of esophageal function is complex, largely owing to the neural coordination required with the oropharynx and transition through different anatomical domains with mixed muscle types. Once a food or liquid bolus enters the esophagus, primary peristalsis strips the food bolus down the length of the esophagus. Peristaltic contraction in the striated muscle esophagus is dependent on central mechanisms that involve sequential activation of excitatory activity of lower motor neurons in the vagal nucleus am-
JAMA May 12, 2015 Volume 313, Number 18 (Reprinted)
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
jama.com
Achalasia
Review Clinical Review & Education
Figure 2. Neural Control of Esophageal Motility and Plot From High-Resolution Esophageal Manometry, With Anatomical Correlates A Parasympathetic esophageal innervation
B Esophageal pressure topography (EPT) plot from high
C Anatomical correlation with EPT plot
resolution manometry (normal study) POSTERIOR
ANTERIOR
0 Dorsal motor nucleus of vagus Rostral Caudal
30
Color pressure scale, mm Hg 60 90 120 150
180
PONS
Esophagus
Cricoid cartilage
Nucleus ambiguus
Vagus nerve
UES Striated muscle
Cervical esophagus
Transition zone
Thoracic esophagus Smooth muscle
Striated muscle innervation Parasympathetic efferent Neuromuscular junction Smooth muscle innervation Preganglionic excitatory neuron Preganglionic inhibitory neuron Postganglionic excitatory neuron cell body Postganglionic inhibitory neuron cell body
Diaphragm (cut) LES
Abdominal esophagus
UES
LES
0
3 Swallow
6
9
12
Time, s
Schematic representation of esophageal motor activity during a swallow A, The esophagus is controlled by both centrally mediated and peripheral intrinsic processes that are compartmentalized based on location in the esophagus and muscle type. B, Output from high-resolution manometry, displayed as esophageal pressure topography (Clouse plot), showing esophageal pressures over time after a single swallow. The x-axis indicates time; the y-axis indicates location from the oropharynx to the stomach, as shown in panel C. Pressure is displayed on a color scale instead of the conventional tracings; thus, a seamless dynamic representation of motor activity is displayed
that provides anatomical representation of the pressure profile. The striated muscle esophagus can be distinguished from the smooth muscle esophagus, as there is a pressure gap at the transition zone that demarcates the introduction of smooth muscle activity. The sphincters are distinguished by the 2 areas of high pressure between the striated and smooth muscle esophagus. LES indicates lower esophageal sphincter; UES, upper esophageal sphincter. Esophageal pressure topography plot reproduced with permission from the Esophageal Center at Northwestern Medicine.
biguus (Figure 2).1 This promotes peristaltic propagation through a sequenced top-to-bottom excitation mediated by release of acetylcholine at the motor end plates (Figure 2).1 Primary peristalsis in esophageal smooth muscle is preceded by inhibition, which stops a progressing peristaltic wave when another swallow is initiated.2,3 This involves patterned activation of preganglionic neurons in the dorsal motor nucleus of the vagus that project onto inhibitory and excitatory neurons in the esophageal myenteric plexus (Figure 2). Under normal circumstances, the inhibitory pathway is activated first to relax the esophagus to promote filling and transport through the esophagus. The inhibitory neu-
rons activated by the preganglionic neurons from the caudal dorsal motor neuron release nitric oxide to promote deglutitive inhibition. This is followed by sequential activation of excitatory neurons, which releases acetylcholine in response to activation by preganglionic neurons arising from the rostral dorsal motor nucleus. The direction and rate of propagation is modulated by the increasing inhibitory influence in the distal esophagus, called the latency gradient.2,3 This essentially delays contractions in the distal esophagus and allows propagation to proceed in an aboral direction. Secondary peristalsis related to distention of the esophagus will elicit a local reflex independent of the vagal input from the dorsal
jama.com
(Reprinted) JAMA May 12, 2015 Volume 313, Number 18
Copyright 2015 American Medical Association. All rights reserved.
Downloaded From: by a Göteborgs Universitet User on 12/23/2017
1843
Clinical Review & Education Review
Achalasia
Box. Symptoms Suggestive of Achalasia That May Prompt Referral for Esophageal Motility Testinga Esophageal Symptoms
Dysphagia (90% of patients) Heartburn (75% of patients) Regurgitation or vomiting (45% of patients) Noncardiac chest pain (20% of patients) Epigastric pain (15% of patients) Odynophagia (50% of swallows are effective without criteria for spasm or jackhammer esophagus
Yes
Modified from Kahrilas et al.50 Classification algorithm based on results of high-resolution manometry with ten 5-mL water swallows. Note that achalasia should be considered in patients presenting with esophagogastric junction outflow obstruction and absent contractility. Failed peristalsis denotes swallows with a distal contractile integral (DCI) less than 100 mm Hg·sec·cm (the DCI quantifies the distal contractile pressure exceeding 20 mm Hg from the transition zone to the proximal aspect of the lower esophageal sphincter [LES] [amplitude × time × length in units of mm Hg·sec·cm]).Panesophageal pressurization denotes uniform pressurization greater than 30 mm Hg extending from the upper esophageal sphincter to the esophagogastric junction. Contractile vigor denotes the strength of distal contraction as defined
topic concluded that using modern technique the risk was less than 1%, comparable to the risk of unrecognized perforation during Heller myotomy.69 Pneumatic dilation should be performed by experienced physicians, and surgical backup is required. Studies using pneumatic dilation as the initial treatment of achalasia have reported excellent long-term symptom control. A third of patients will relapse in 4 to 6 years and may require repeat dilation. Response to therapy may be related to preprocedural clinical parameters, such as age (favorable if >45 years), sex (more favorable among females than males),70 esophageal diameter (inversely related to response), and achalasia subtype (type II better than I and III).52,71 Although surgical myotomy has a greater response rate than a single pneumatic dilation, it appears that a series of dilations is a reasonable alternative to surgery. A recent randomized trial compared this type of graded strategy with surgical myotomy and found it to be noninferior in efficacy (Table 3).55 Addition of botulinum toxin injection does not appear to improve outcomes.62 1848
Normal esophageal motor function a
by the DCI. Ineffective esophageal motility (IEM) is diagnosed when a patient exhibits greater than 50% ineffective swallows (ineffective swallows are either failed [DCI
