Practical Approaches to Caused by Esophageal Motor Disorders Amindra S. Arora, MB BChir and Jeffrey L. Conklin, MD

Address nonspecific esophageal motor disorders (NSMD), diffuse Division of and , Mayo Clinic, (DES), nutcracker (NE), 200 First Street SW, Rochester, MN 55905, USA. hypertensive lower esophageal (hypertensive E-mail: [email protected] LES), and achalasia [1••,3,4••,5•,6]. Out of all of these Current Gastroenterology Reports 2001, 3:191–199 conditions, only achalasia can be recognized by Current Science Inc. ISSN 1522-8037 Copyright © 2001 by Current Science Inc. or radiology. In addition, only achalasia has been shown to have an underlying distinct pathologic basis. Recent data suggest that disorders of esophageal motor Dysphagia is a common symptom with which patients function (including LES incompetence) affect nearly present. This review focuses primarily on the esophageal 20% of people aged 60 years or over [7••]. However, the motor disorders that result in dysphagia. Following a brief most clearly defined disorder to date is achalasia. description of the normal mechanisms and the Several studies reinforce the fact that achalasia is a rare messengers involved, more specific motor abnormalities condition [8•,9]. However, no population-based studies are discussed. The importance of achalasia, as the only exist concerning the prevalence of most esophageal motor pathophysiologically defined esophageal motor disorder, disorders, and most estimates are derived from people with is discussed in some detail, including recent developments symptoms of chest and dysphagia. A recent review of in pathogenesis and treatment options. Other esophageal the epidemiologic studies of achalasia suggests that the spastic disorders are described, with relevant manometric worldwide incidence of this condition is between 0.03 and tracings included. In recent years, the importance of 1.1/105/year [9]. The prevalence of diffuse esophageal gastroesophageal reflux as a primary cause of esophageal spasm is similar to that of achalasia, whereas other dysmotility has been recognized, and this is also discussed. disorders (eg, and nonspecific eso- In addition, the motility disturbances that develop after phageal motility disorders) are more common [1••,4••]. surgical fundoplication are reviewed. This review focuses on the normal mechanism whereby the esophagus contracts. The various motility disorders are then discussed, followed by disorders of swallowing caused Introduction by gastroesophageal reflux disease (GERD) and the The esophagus and its serve to transport surgical treatments used for GERD. boluses from the to the and to protect the upper aerodisgestive tract from the reflux on noxious gastric contents. The act of swallowing is comprised of an Esophageal Motility elaborately timed series of events requiring intact central, Central neural stimulation studies clearly demonstrate that autonomic, and enteric nervous systems as well as a set of the motor nuclei providing innervation to the muscles functional striated and smooth muscles [1••,2,3,4••]. Any used in swallowing are located in the . However, interference with these precise mechanisms will result in the neural circuitry is complex, as direct stimulation of dysphagia (dys = abnormal, phagia = swallow). This article these motor nuclei does not produce swallowing directly concentrates on the esophageal motor disorders that result [7••,10,11•]. The following section describes the in dysphagia. In addition, the various forms of therapy and electrical physiology of the esophagus. available to treat these problems are discussed. Disorders of esophageal motility have been described Anatomy and physiology of the esophagus for centuries. Furthermore, disordered esophageal motility The elastic pharyngeal layer becomes the muscularis has been linked to various “chest spasms” as well as dys- mucosa of the esophagus at the level of the cricoid carti- phagia. Only recently, in the latter half of the twentieth lage. In humans, the muscularis mucosa is a thin muscular century, has the technology to monitor the esophageal layer that is positioned just beneath the mucosa. Although motor response been applied regularly to patients. Using it is the innermost component of the neuromuscular appa- esophageal manometric equipment, a number of motor ratus of the esophagus, it plays little role in the esophageal disorders have been described. These conditions include, motor function [12]. The is located deep in the 192 Esophagus muscularis mucosa, and is covered by the inner circular Esophageal is a stereotyped event. It starts and outer longitudinal fibers of the muscularis externa. with the longitudinal muscles of the esophagus contracting Striated muscle comprises the proximal 5% of the muscu- in sequence to produce a shortening of the esophagus. A laris externa; the next 40% is a mixture of smooth and ring-like contraction of the circular muscles then sweeps striated muscles in varying proportions, and the distal 55% along the esophagus to propel the to the stomach. to 60% is comprised solely of [12]. The The primary peristaltic wave is thought to arise from an myenteric of Auberbach is a flat neural network of initial hyperpolarization of the circular smooth muscle ganglia and interconnecting fibers located between down the length of the smooth muscle. This wave of hyper- the longitudinal and circular layers of the esophagus. The polarization is triggered by swallowing, starts nearly simul- nerve cells of the receive inputs from taneously at all levels of the smooth muscle esophagus, and other within the plexus and from the central ner- results from the release of (NO) from myenteric vous system (CNS). Myenteric neurons send to the neurons innervating the circular smooth muscle cells. It smooth muscle of the esophagus and other neurons within is quickly followed by a depolarization that generates a the plexus. The density of nerve fibers innervating the rebound contraction of the smooth muscle. The peristaltic smooth muscle esophagus is highest at the proximal edge contraction wave is generated because the duration of the of the smooth muscle segment and decreases substantially hyperpolarization increases along the length of the before reaching the gastroesophageal junction. In addi- esophagus. Secondary peristalsis is formed by esophageal tion, some ganglia are found in the striated portion of the contractions that arise in the absence of a swallow and is an esophagus, the function of which is still unknown. There is entirely intramural event during which the is no of Meissner in the esophagus, inactive [16]. Tertiary peristalsis (or autonomous perist- unlike the rest of the gastrointestinal (GI) tract [12,13••]. alsis) occurs in the extrinsically denervated esophagus. The striated muscles of the pharynx and esophagus Before leaving our discussion of the neuromuscular receive their extrinsic innervation from vagal neurons, the function of the various regions of the esophagus, it is cell bodies of which are located in the ambiguus of important to mention that the motor output from both the the brainstem. These axons innervate the striated muscle vagus nerve and the sympathetic can fibers in the form of motor endplates [10,11•]. On the other be modulated by the sensory innervation arising within , the extrinsic nerve supply to the smooth muscle of the the esophagus. In the cervical esophagus, sensory afferents esophagus is derived from the dorsal motor nucleus of the travel to the CNS with the , whereas vagus. These parasympathetic preganglionic fibers travel the more distal esophageal sensory information is carried down the vagus and form a on neurons within the by the recurrent laryngeal nerve or esophageal branches of plexus of Auberbach. Modulation of the neural activity of the the vagus. Recent studies demonstrate that a number of plexus of Auerbach is further enhanced by sympathetic fibers esophageal motor disorders are associated with a variety of originating from the superior cervical ganglion (from T4 to neural defects involved in the central processing of infor- T6) and traveling with the vagal fibers [10,11•,12]. mation. For instance, patients with diffuse esophageal The coordinated activity of the neuromuscular apparatus spasm and nutcracker esophagus have abnormal cortical produces a peristaltic wave within the esophagus. The evoked potentials in response to esophageal stimulation as primary peristaltic wave is triggered in the CNS, as bilateral well as abnormal esophageal motor evoked potentials in vagotomies will abolish it. The progression of the peristaltic response to cerebral stimulation [17•]. wave down the esophagus follows an innate pathway. The The lower esophageal sphincter is defined manometric- striated muscles within the upper esophagus only receive an ally as a zone of high pressure between the esophagus and excitatory input from the medullary swallowing center via stomach that relaxes with swallowing. The circular muscles the vagus nerve [10,11•,12,13••,14,15]. The patterned acti- of the LES, unlike the rest of the esophagus, are tonically vation of these neurons in the swallowing center results in contracted. Relaxation of the LES produced by swallowing the sequential activation of striated muscles to produce is mediated by the vagal activation of inhibitory myenteric peristalsis. The programming of peristalsis in the smooth- neurons that supply the LES muscle. Whereas these muscle esophagus is more complex and depends upon a pre- neurons contain both vasoactive intestinal peptide (VIP) cise interplay among the CNS, the myenteric plexus, and the and nitric oxide synthase (NOS), NO is the primary media- smooth muscle of the esophagus. In the smooth-muscle tor of swallow-induced LES relaxation [7••,18]. In addi- esophagus, the behaves as a switch tion, gastric dilation or pharyngeal stimulation triggers a that initiates a peripheral program in the myenteric plexus second form of LES relaxation, so-called transient LES and smooth muscle to produce peristalsis. The smooth relaxation. The role of transient LES relaxation is probably muscle of the esophagus receives both excitatory (primarily to relieve the pressure build-up during gastric distention. cholinergic) and inhibitory (primarily nitric oxide) inputs The transient LES relaxation depends upon both the CNS from the myenteric plexus. The interplay of these inputs with (swallowing center) and , but the the smooth muscle controls the amplitude and timing of the details of the neural circuitry are incompletely understood. peristaltic wave. The CNS may reflexively modulate these The esophagus undergoes relatively minor structural characteristics of the primary peristaltic wave. and functional changes with aging. Some studies have Dysphagia in Esophageal Motor Disorders • Arora and Conklin 193

Figure 1. A typical esophageal motility tracing in a healthy individual. The LES pressure is 22 mm Hg, with relaxation to the baseline with the wet swallow (WS). In addition, peristaltic waves are seen. The scale for the esophageal leads is 100 mm Hg.

demonstrated a decrease in the number of ganglion cells in luminal pressures. Achalasia is remarkably similar to Chagas’ the plexus of Auerbach, and motility studies have shown disease, although infective causes of achalasia remain specula- decrease in peristaltic amplitudes only [7••]. Primary tive at present. Robertson et al. [19] have demonstrated an peristalsisis was normal in healthy elderly volunteers, but increased frequency of varicella-zoster virus (VZV) DNA in secondary peristalsis was less frequent. Most of the the myenteric neurons of patients with achalasia. This finding swallowing difficulties encountered in older patients is tantalizing because VZV is a neurotropic virus. However, the involves problems in initiating the swallow. primary pathologic finding of degeneration of the myenteric neurons in achalasia is unexplained. In addition, autoanti- bodies that recognize a 62-kD protein expressed on the myen- Disorders in Esophageal Motor Function teric plexus have been demonstrated in 60% of patients with Abnormalities in the motility of the smooth and striated achalasia, although it is unclear whether this represents a muscles of the esophagus can lead to symptoms of chest direct neurotoxic effect or an epiphenomenon that occurs pain and dysphagia. From the outset, it should be once achalasia develops [19,20]. noted that esophageal motility disorders are defined The esophagi of patients with achalasia, however, manometrically (occasionally radiologic evaluations can be demonstrate a number of common findings: 1) decreased used in determining motility disorders). Furthermore, myenteric neurons; 2) near absence of inhibitory motor symptoms are poorly correlated with the presence of eso- neurons containing vasoactive intestinal polypeptide (VIP) phageal motor disturbance, and the interpretation of motil- and NOS; and 3) alteration to varying degrees of excitatory ity data is subjective. Figure 1 shows a normal esophageal motor neurons containing and tachykinins manometric tracing with esophageal peristalsis and relax- [21•]. These findings suggest that achalasia involves a ation of the LES. No ideal classification exists for most of inhibitory neurons predominantly with esophageal motor disorders; only achalasia, , preservation of the cholinergic motor neurons in the and Chagas’ disease are defined by identifiable histopatho- esophagus and LES to some degree. The loss of the inhibi- logic changes. The remaining motor disorders (DES, NE, tory innervation results in impaired LES relaxation and a hypertensive LES, and NSMD) do not have an identifiable loss of peristalsis, whereas NO donors actually relax the etiology or . The modern classification of LES in achalasia. Histopathologic findings have led to esophageal motility disorders is outlined in Table 1. clearer understanding of achalasia and different treatment paradigms. The enteric nervous system abnormalities seen Achalasia in achalasia are located not only in the LES and esophagus Etiology but also involve the gastric fundus and occasionally Achalasia (a = without, chalus = relaxation) is a disease of the small bowel. unknown etiology that is characterized by an absence of peri- stalsis in the smooth-muscle esophagus and failed or incom- Clinical features plete LES relaxation. It is frequently associated with a tonically The manifestations of primary achalasia are protean. Often contracted LES that generates greater than normal intra- symptoms are present for several years before the patient 194 Esophagus

Table 1. Classification of esophageal symptoms, radiologic and manometric, of achalasia. Apart motility disorders from identifying a dilated esophagus with retained food/ fluid, endoscopy is not sensitive in diagnosing achalasia. Achalasia An endoscopic clue to the presence of pseudoachalasia is Absence of peristalsis in the smooth muscle component an increased resistance to passage of the endoscope across of the esophagus Elevated intra-esophageal baseline pressure (compared the LES, rather than the gentle passage across the LES that to gastric baseline) is seen in primary achalasia. Other imaging modalities Incomplete LES relaxation (can be normal in 30% of cases) may be necessary to rule out pseudoachalasia, including Elevated LES pressure (not always seen) CT scan of the chest and , and possible endo- scopic ultrasound (EUS). However, reports conflict with Simultaneous contraction in the smooth muscle portion regard to the normal appearance of the lower esophagus of the esophagus (>3/10 wet swallows) Periods of normal peristalsis on EUS in patients with primary achalasia [22]. An impor- Occasional spontaneous/repetitive contractions tant but rare complication of primary achalasia is the Prolonged duration of some contractions (>6 seconds) development of a squamous-cell of the esopha- Nutcracker esophagus gus. Consequently, the onset of dysphagia following treat- Mean distal esophageal amplitude >180 mm Hg ment of primary achalasia should prompt a thorough Occasional repetitive prolonged contractions search for malignant transformation. However, the actual Hypertensive lower esophageal sphincter risk of developing is still low, and surveillance Elevated resting LES >40 mm Hg Normal LES relaxation with wet swallows endoscopy is not advocated. Normal peristalsis Nonspecific motility disorder Therapy Abnormal peristalsis that does not meet the criteria for The underlying cause of primary achalasia is a loss of other motor disorders inhibitory myenteric neurons in the plexus of Auerbach. Reduced amplitude (ineffective esophageal peristalsis) There is no treatment to reverse or halt this degeneration <30 mm Hg and loss [23,24•]. However, treatment regimens are aimed Triple peaked contraction waves Prolonged/spontaneous/simultaneous contractions at reducing the functional obstruction that is caused by the contraction of the LES, thereby enabling gravity to compensate for the lack of peristalsis and LES relaxation comes to medical attention [1••]. The major symptoms [25]. Success is monitored by improvement in symptoms, include dysphagia to both solids and liquids, regurgitation, although functional improvement can be measured mano- recurrent pneumonia, (from fermentation of metrically as a decrease in LES tone and radiographically as retained food in the esophagus), weight loss, and foul more rapid passage of barium into the stomach. breath. Often patients will have devised maneuvers to help Until recently, the most effective therapies for treating the food down (eg, stretching during meals, water primary achalasia involved a mechanical disruption of the with each bite). Often is a major feature in the LES, either by forceful pneumatic dilatation or a Heller patient symptom complex, although its underlying cause is myotomy. Regular dilation of the esophagus with standard unknown; chest pain may be caused by the chronic stimu- polyvinyl bougies is of limited benefit, although no con- lation of in the myenteric plexus [8•]. trolled trials substantiate this observation [4••]. Forceful dilation along with pneumatic dilation is thought to work Diagnosis by causing a more complete tearing of the LES muscle The diagnosis of primary achalasia is based on three layer, although, again, no studies document this belief. criteria: 1) appropriate manometric evidence; 2) character- There is no standard way in which pneumatic dilation is istic radiographic findings; and 3) absence of a malignancy performed, and studies differ with regard to the size of affecting the gastroesophageal junction or cardia. The dilator, the maximum inflation pressure, the rate of infla- manometric parameters used to diagnose achalasia are tion, and the duration of maximal inflation. Notwith- aperistalsis of the esophagus, simultaneous isobaric waves standing these methodologic problems, most studies consistent with a common-cavity phenomenon, failure of report good to excellent response rates (as measured LES relaxation (however, 30% of patients have LES relax- by symptoms). However, it is clear that nearly half the ation), and elevated LES pressure (not necessary in all patients will require further dilation after 4 to 5 years and cases). An example of a typical manometric tracing in that further dilations are less effective. The consensus holds achalasia is shown in Figure 2. The radiographic features of that 50% of patients with primary achalasia treated with achalasia can demonstrate a dilated esophagus with an air- pneumatic dilation will require retreatment in 5 years but fluid level, or a “bird-beak” appearance of the distal eso- are unlikely to respond fully. Several factors seem to pre- phagus, representing the tapered, contracted LES. Endo- dict whether patients will respond well to pneumatic scopic evaluation in achalasia is performed to exclude dilation. Poor responders seem to be younger patients secondary (usually malignant) disorders that mimic the (under 40 years) and those with a post-dilation LES Dysphagia in Esophageal Motor Disorders • Arora and Conklin 195

Figure 2. A typical manometric tracing of a patient with achalasia. The vertical scale is set at 10 mm Hg increments (to a maximum of 50 mm Hg). Note the elevated LES pressure (about 40 mm Hg) that does not relax with the wet swallow (WS). In addition, there is no esophageal body peristalsis. The waves seen are superimposable (so-called “isobaric waves”) upon each other and represent a common cavity phenomenon.

pressure greater than 20 mm Hg [4••,26]. In contrast, the severe side effects associated with nitrates (mainly duration of symptoms, gender, size of balloon dilator, and headaches) and tachyphylaxis have limited their effective- esophageal diameter are not predictors of a poor response ness. In contrast, the calcium-channel antagonists are [4••]. Mortality following pneumatic dilation is uncom- thought to act as direct LES relaxants, although the success mon (<0.5%), although the risk of perforation is higher of these (mainly nifedipine, verapamil, and (2% to 6%), and about 2% to 3% of patients will develop diltiazem) has been variable [30]. to treat gastroesophageal reflux (GER). achalasia is “inconvenient, often ineffective and frequently Surgical myotomy is the alternative to balloon dilation. associated with side-effects,” according to Bassotti and Most surgeons perform a modified using Annesse [31]. A recent study of , a type 5 (cyclic a laparoscopic procedure. To prevent GER, a loose fun- GMP) phosphodiesterase inhibitor, suggests that it may doplication is often performed (270-degree wrap or Toupet have some short-term efficacy in the treatment of achalasia procedure). Surgical myotomy results in excellent symp- [32•]. The rationale for its use is that sildenafil, like NO, tom relief, with mortality rates similar to those with increases cellular concentrations of cyclic GMP to produce balloon dilation [27,28]. Using the laparoscopic method relaxation of the LES smooth muscle. for the myotomy shortens the hospital stay considerably Another pharmacologic therapy has concentrated (when compared with the open surgical method), and on diminishing the effects of acetylcholine at the LES rather patients are often back to work within 2 to 4 weeks. Retro- than boosting the levels of NO. is an spective reviews comparing surgical myotomy with extremely potent poison that inhibits the release of acetyl- balloon dilation either demonstrate equivalence between at the presynaptic terminals. This toxin rapidly the two methods or surgical superiority for both short-term binds to presynaptic cholinergic terminals, becomes inter- and long-term relief of symptoms [27]. nalized, and inhibits the release of acetylcholine by interact- The medical therapy available for achalasia was ing with a synaptosomal protein (SNAP-25). This decreases disappointing until the introduction of botulinum toxin A the excitatory input from acetylcholine, and the LES pressure (BTX). Nitrates, both long and short acting, as well as falls by over 30% [23,24•]. Since 1995, when Pasricha calcium-channel antagonists, have been used to relax the demonstrated the effectiveness of locally injected BTX into smooth muscle of the esophagus and LES. Several reports the lower esophagus, several other studies have defined its have demonstrated varying efficacy with these medications use more clearly. The effect of BTX is short acting, as new in achalasia. For example, studies have shown that 5 to 10 are formed and repeated injections are required mg of administered sublingually may [23,24•,27,31]. Ultimately, it loses its effectiveness because improve dysphagia in up to 70% of patients with achalasia antibodies are formed against it. In view of its cost and short [29••]. The mechanism by which nitrates are thought to duration of action, BTX should be used to treat patients who exert their influence is by acting as NO donors. However, are too frail to undergo a more definitive disruption of the 196 Esophagus

LES by dilation or surgery. As a note of caution, prior BTX The etiology of spastic esophageal disorders is unclear can interfere with subsequent surgical myotomy because because of an incomplete relationship between symptoms tissue reaction to this agent leads to a loss of definition in and manometric findings. Indeed, it is clear that several the fascial planes predisposing to the mucosal perforations patients with chest have normal esophageal motility that have been reported. However, BTX has shown us that tracings, whereas a number of patients with abnormal the paradigm for treating achalasia can be changed, and that manometries are asymptomatic (Fig. 3). Esophageal symp- in the future mechanical disruption may not be the only toms correlate poorly with manometric diagnoses of non- treatment for primary achalasia. specific spastic disorders. Up to a third of morbidly obese individuals have abnormal esophageal traces yet have no Gastroesophageal reflux disease symptoms, whereas diabetic patients demonstrate a high Etiology frequency of abnormal esophageal motility irrespective of Gastroesophageal reflux is a physiologic event that occurs in autonomic dysfunction [36•]. Clearly, the etiology is more most people. However, gastroesophageal reflux disease is complex than autonomic dysfunction, and visceral hyper- defined as exposure of the distal esophagus to for greater sensitivity may be intimately involved in the pathogenesis than 4% to 5% of the time in a 24-hour period. The develop- of symptomatic spastic esophageal motor disorders. ment of GERD involves a number of factors: 1) excess tran- Furthermore, neuromodulators such as antidepressants sient LES relaxations (TLESR); 2) decreased esophageal have proved to be useful in treating patients with these clearance; 3) poor LES tone; and 4) gastric distention spastic disorders. Handa et al. [37••] recently showed that [33,34]. In healthy subjects, primary esophageal peristalsis is low-dose tricyclic antidepressants are effective in treating the initial response to acid reflux. However, in the supine patients with diffuse esophageal spasm and pain for at position and during sleep, secondary peristalsis accounts for least several months. Using another strategy, symptom- most esophageal reflux clearance [33]. Patients with GERD based therapy, studies have shown that low-dose antide- have impaired esophageal motor responses to clear the pressants can be effective in treating patients with non- refluxate, reflected by fewer peristaltic responses, increased cardiac chest pain regardless of their underlying esoph- intervals between peristalsis, and fewer secondary peristaltic ageal disorder [37••,38]. More recently, the role of GERD waves. These developments have two confounding influ- in patients with non-cardiac chest pain and spastic esoph- ences on the development of symptoms and esophageal ageal disorders has become more intriguing. Seventy . First, the abnormal esophageal motor response percent of patients with nutcracker esophagus were subse- fails to clear the refluxate, thereby increasing contact time quently diagnosed with GERD (either by an abnormal between the esophagus and injurious acid or . Second, upper endoscopy or an abnormal 24-hour ambulatory pH poor esophageal motility may not transport neutralizing study), and most of them derived significant symptom down the esophagus efficiently. The corollary is also relief with antacid therapy [38]. This was seen despite the true, in that esophageal peristalsis (both primary and second- fact that their manometry remained abnormal. ary) is improved after treatment of reflux . No controlled studies have demonstrated a significant The current paradigm for treating GERD involves acid improvement in symptoms of diffuse esophageal spasm neutralization rather than trying to improve esophageal following pneumatic dilation or even surgical myotomy. peristalsis. The use of cisapride (no longer available in the With respect to muscle relaxant therapies, most reports are United States) may have led to improved esophageal anecdotal. The only randomized, controlled crossover trial motor response as well as gastric emptying. In a recent demonstrated no effect of diltiazem in the treatment of development, the modulation of TLESR has been described diffuse esophageal spasm. In summary, the evidence in dogs and humans. It is now recognized that these events supports the use of tricyclic antidepressants (low-dose may be paramount in development of GERD. Baclofen, a trazodone, 50 mg at night, increasing by 25 mg every 2 to 3 gamma aminobutyric acid (GABA) antagonist, has been weeks up to a maximum dose of 125 to 150 mg at night) or shown to decrease the number of TLESR produced [35]. aggressive treatment of underlying GERD.

Esophageal spastic disorders Post-fundoplication motor disorders Even now, the etiology of the various esophageal spastic Nissen described fundoplication for the treatment of disorders is poorly understood. Rate et al. [17•] showed GERD in the 1950s. Early on, it became clear that a major that spastic esophageal motor disorders are characterized side effect was the development of dysphagia that was by a number of abnormalities in esophageal neuro- usually transient. Dysphagia occurs in the majority of muscular physiology that do not correlate with mano- patients immediately after surgery, but after a year, the metric findings. The inconclusive and poorly defined proportion of patients complaining of dysphagia is quite abnormalities within the central processing units of the small [39,40]. Studies of the traditional open fundopli- CNS as well as the esophageal receptors demonstrate the cation suggest that there may be increases in LES pressure vagueness of spastic esophageal disorders. The diagnostic and the amplitude of the distal esophageal pressure waves criteria for these disorders are delineated in Table 1. following surgery. Improvement was seen in those patients Dysphagia in Esophageal Motor Disorders • Arora and Conklin 197

Figure 3. Motility tracings in esophageal spastic disorders. A, Tracing of diffuse esophageal spasm. Note the simultaneous triple peaked esophageal waves that are prolonged in duration (>7 seconds) in the second section. This is preceded with a near normal peristaltic tracing. B, Tracing of nutcracker esophagus. Note the high amplitude (250 mm Hg) esophageal peristaltic waves. WS—wet swallow.

undergoing a complete procedure (360-degree wrap), more troublesome than those who feel more in control of compared with those who had looser wraps [40,41••]. Few their own situation. Psychological testing and support may studies have compared open procedures with laparoscopic improve dysphagia after fundoplication in this group fundoplications, but no significant differences were noted [43••,44]. In the majority of patients, dysphagia after fun- between the LES pressure and esophageal amplitudes in doplication is treated by dilation (balloon or bougie). the two interventions. One earlier study by Ireland et al. [42] suggests that fundoplication (open procedure) reduced TLESR, but further work is needed to confirm this Conclusions observation. More recent publications indicate that Esophageal motor disorders are common. However, to patients who are more introspective and fatalistic may per- date only achalasia has a well-defined histopathologic cor- ceive swallowing difficulties after fundoplication as being relation. The other spastic motor disorders can be assoc- 198 Esophagus

Figure 4. A practical approach to diagnosing esophageal motor disorders

iated with symptoms, although it is clear that visceral 4.•• Spechler SJ: AGA technical review on treatment of patients hypersensitivity may play a more important role in symp- with dysphagia caused by benign disorders of the distal esophagus. Gastroenterology 1999, 117:233–254. tom production. The importance of GERD in the symptom The technical and official view that evaluates the various treatment complex of patients with spastic esophageal motor disor- options available for the dysphagic patient. Very thorough and ders should not be overlooked. Results to date do not sup- up-to-date article. The section on achalasia is comprehensive and should serve as a reference to us all. port the treatment of asymptomatic esophageal motility 5.• DiMarino AJ, Allen ML, Lynn RB, et al.: Clinical value of disorders (except for achalasia). It is also clear that GERD esophageal motility testing. Dig Dis Sci 1998, 16:198–204. itself can produce a motor disorder that is often correctable Clearly written treatise on the uses for esophageal motility testing. The authors discuss the utility of motility testing in patients with after treatment. A practical approach to diagnosing esoph- dysphagia as well as GERD and non-cardiac chest pain. ageal motor problems is shown in Figure 4. 6. Pirtniecks A, Smith LF, Thorpe JAC: Autonomic dysfunction in non-specific disorders of oesophageal motility. Eur J Cardiothorac Surg 2000, 17:101–105. 7.•• Plant RL: Anatomy and physiology of swallowing in adults References and Recommended Reading and geriatrics. Otolaryngol Clin North Am 1998, 31 : 477–488. Papers of particular interest, published recently, have been This article includes an excellent section on the normal physiology highlighted as: of swallowing. The author clearly explains the mechanics of • Of importance swallowing as well as the neural integration. •• Of major importance 8.• Howard PJ, Maher L, Pryde A, et al.: Five year prospective study of the incidence, clinical features and diagnosis 1.•• Kahrilas PJ: Esophageal motility disorders: current concepts of achalasia in Edinburgh. Gut 1992, 33:1011–1015. of pathogenesis and treatment. Can J Gastroenterology One of the earlier studies to determine the frequency of achalasia. 2000, 3:221–231. 9. Podas T, Eaden J, Mayberry M, et al.: Achalasia: a critical A very clear standard description of motor disorders in the esophagus. review of epidemiological studies. Am J Gastroenterol 2. Pouderoux P, Lin S, Kharilas PJ: Timing, propagation, 1998, 93:2345–2347. coordination, and the effect of esophageal shortening 10. Mujica VR, Conklin J: When it is hard to swallow. Postgrad Med during peristalsis. Gastroenterology 1988, 94:73–80. 1999, 105:131–145. 3. Hudson HM, Daubert CR, Mills RH: The interdependancy 11 . • M i l e r A J : The search for the central swallowing pathway: of protein-malnutrition, aging and dysphagia. Dysphagia the quest for clarity. Dysphagia 1993, 8:185–194. 2000, 15:31–38. The central control of swallowing is difficult to explain. This article does a good job with clear diagrams. 12. Biancani P, Behar J: Esophageal motor function. In Textbook of Gastroenterology, edn 2. Edited by Yamada T. Philadelphia: Lippincott Williams & Wilkins; 1995:158-179. Dysphagia in Esophageal Motor Disorders • Arora and Conklin 199

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