Surgical myotomy for achalasia

INTRODUCTION — 

Achalasia is a primary esophageal motility disorder characterized by aperistalsis and defective relaxation of the lower esophageal sphincter (LES) in response to swallowing. The goal of treatment is to eliminate the resistance of the abnormal LES, allowing passage of the ingested food from the esophagus into the stomach by gravity and pressurization of the esophagus by the pharynx [1]. (See "Achalasia: Pathogenesis, clinical manifestations, and diagnosis".)

Medical therapies, which are nonspecific and have inconsistent results and side effects, have a limited role in the treatment of achalasia [2]. Instead, three effective endoscopic or surgical treatment modalities are available today: pneumatic dilation, peroral endoscopic myotomy (POEM), and laparoscopic or robotic Heller myotomy with a partial fundoplication. Some controversy exists as to whether endoscopic or surgical therapy should be initiated first [3]; this is discussed elsewhere. (See "Overview of the treatment of achalasia".)

The preoperative evaluation, surgical techniques, and postoperative results of surgical myotomy will be reviewed here. Details of the other two procedures, pneumatic dilation and the POEM procedure, are discussed elsewhere. (See "Pneumatic dilation and botulinum toxin injection for achalasia" and "Peroral endoscopic myotomy (POEM)".)

EVALUATION OF MYOTOMY AS A TREATMENT FOR ACHALASIA — 

Myotomy simply means to disrupt a defective, and often hypertensive, low esophageal sphincter (LES) to allow food to pass from the esophagus to the stomach. The LES can be disrupted with either pneumatic dilation (which blindly breaks the fibers of the LES by inflation of a balloon), or surgical or endoscopic myotomy (which transects the circular fibers of the LES under direct vision).

●Pneumatic dilation – Pneumatic dilation is used for patients who prefer to avoid surgery, have undergone multiple prior abdominal operations, or would be unable to tolerate the pneumoperitoneum required to perform the procedure laparoscopically (eg, restrictive pulmonary disease, chronic heart failure). However, a network meta-analysis that included 16 studies and 590 patients found that patients undergoing laparoscopic Heller myotomy had superior short- and long-term efficacy compared with patients undergoing endoscopic balloon dilatation (odds ratio [OR] 2.2, 95% CI 1.2-4.19 at 12 months, and OR 29.8, 95% CI 34-224.7 at 60 months) [4]. (See "Pneumatic dilation and botulinum toxin injection for achalasia".)

●Surgical myotomy – Surgical myotomy was first described in 1913 by Ernest Heller, who performed both anterior and posterior incisions at the gastroesophageal junction [5]. His technique was modified to include only the anterior myotomy. The modified Heller myotomy is the most common operative procedure used to treat achalasia [6]. The operation can be performed using an open or a minimally invasive technique, and the esophagus can be approached through the abdomen or thorax [3,7-13]. With advances in minimally invasive surgery in the early 1990s, the thoracoscopic and laparoscopic approach, and later the robotic approach became popular [9-12,14]. There are advantages and disadvantages to each approach. The main disadvantages of a thoracoscopic approach compared with a laparoscopic/robotic esophageal myotomy include limited exposure of the distal LES and stomach and the technical challenges of performing a fundoplication. With regard to clinical outcomes, the thoracoscopic approach is associated with a higher rate of residual or recurrent dysphagia (because of the shorter gastric myotomy), gastroesophageal reflux, more postoperative pain, and a longer hospital stay [15]. In current practice, the laparoscopic or robotic Heller myotomy with fundoplication has become the standard surgical treatment for achalasia worldwide [16].

●Peroral endoscopy myotomy (POEM) – Alternatively, esophageal and gastric myotomy can be accomplished endoscopically with the POEM procedure at select centers as an alternative to Heller myotomy. POEM utilizes the principles of submucosal endoscopy to transform the submucosal layer in the esophagus and proximal stomach into a tunnel through which esophageal and gastric myotomy are carried out using a flexible endoscope. (See "Peroral endoscopic myotomy (POEM)".)

In a randomized trial, POEM achieved similar relief of dysphagia at two years compared with laparoscopic Heller myotomy with Dor fundoplication but much higher rates of gastroesophageal reflux disease (GERD)-related esophagitis at 3 (57 versus 20 percent) and 24 months (44 versus 29 percent) [17]. A subsequent meta-analysis including 20 retrospective observational studies with a total of 5139 patients demonstrated no differences in intraoperative or postoperative complications, reintervention rate, occurrence of GERD symptoms, use of proton inhibitors, or esophagitis between laparoscopic myotomy and POEM [18].

Thus, both laparoscopic or robotic Heller myotomy with partial fundoplication and POEM are first-line therapies for patients with a confirmed diagnosis of achalasia [2,19,20]. The choice can be made based on institutional expertise and resources. Additionally, some experts prefer POEM for type III (spastic) achalasia because of the possibility of a longer myotomy, and other experts prefer surgical myotomy for young patients to avoid potentially long-term proton pump inhibitor use. However, such preferences are based upon mostly expert opinion and limited data. These issues are discussed in detail in another topic (algorithm 1). (See "Overview of the treatment of achalasia".)

PREOPERATIVE EVALUATION — 

The diagnosis of achalasia is based upon the clinical history, barium swallow, upper endoscopy, and esophageal manometry. The key component for selecting appropriate patients for surgical management is to differentiate achalasia from other motility disorders and from pseudoachalasia, malignancy, and mechanical obstruction.

History and physical examination — The preoperative evaluation by the surgeon includes a history of patient symptoms as well as a review of previous studies and the results of medical therapies to alleviate symptoms. As an example, patients who are older than 50 years with symptoms of less than six months' duration and/or who have lost more than 10 pounds (4.5 kg) must be evaluated for esophageal cancer.

Pertinent details of the preoperative assessment include:

●Age

●History of weight loss

●Quality of symptoms (dysphagia, regurgitation, chest pain, etc)

●Duration of symptoms

●Physiologic studies of esophageal function

●Results of dilatations

●Botulinum toxin injections

●Biopsy results

●Previous intra-abdominal and intrathoracic surgery

●Comorbid illnesses

Diagnostic evaluation — Esophageal manometry, endoscopy, and a barium swallow study are essential to confirming the diagnosis of achalasia, and the studies should be personally reviewed by the surgeon before proceeding with an operation. (See "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'Diagnostic evaluation'.)

●Manometry – Manometry is the measurement of muscular function of the esophagus in three zones: the lower esophageal sphincter, esophageal body, and upper esophageal sphincter. High-resolution manometry (HRM) is preferred because it provides for a more accurate characterization of esophageal function compared with standard manometry (figure 1 and picture 1) [21]. HRM permits continuous recording of motor activity along the entire length of the esophagus and yields a more complete and detailed picture of esophageal motility. Manometry systems include a catheter with multiple pressure sensor channels, pressure transducers, and a recording device with a computer for analysis. The technique and the interpretation of the results are discussed elsewhere. (See "Overview of gastrointestinal motility testing", section on 'Esophagus' and "Oropharyngeal dysphagia: Clinical features, diagnosis, and management", section on 'Manometry' and "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'High-resolution manometry' and "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'Esophageal manometry'.)

●Endoscopy – Most patients undergo endoscopy to establish a diagnosis well in advance of consideration for surgery. It is important that the surgeon review the results to exclude other etiologies of the symptoms. It is not necessary to routinely repeat the endoscopy before every operative procedure, but the surgeon must have a low threshold to repeat endoscopy if concomitant or alternative upper gastrointestinal disease remains a consideration. (See "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'Upper endoscopy'.)

●Radiographic imaging – The barium swallow is the preferred initial study to define the esophageal anatomy (image 1). This study will show the extent of esophageal dilation, shape, and gastroesophageal junction obstruction. Absence of obstruction at the gastroesophageal junction, which is characterized by a column of barium with air-fluid levels, should make one question the diagnosis. Some groups have advocated performing a timed barium swallow to better assess achalasia [22].

Routine computed tomography (CT) scans of the chest and abdomen are not necessary, but if pseudoachalasia is suspected based on the clinical history, a CT scan or endoscopic ultrasound should be performed to ensure accuracy of diagnosis. A sigmoid esophagus is a complication of long-standing achalasia. The surgical approach to a sigmoid esophagus may be to limit the procedure to myotomy without fundoplication or an esophagectomy for patients with prior attempts at myotomy or megaesophagus. (See 'Sigmoid megaesophagus' below.)

Ambulatory pH monitoring is not necessary in the work-up of patients with achalasia. It should be performed only in patients with heartburn and dysphagia who are considered to have gastroesophageal reflux refractory to medical treatment. In these patients, this test will distinguish reflux from achalasia [23].

SURGICAL MYOTOMY — 

Heller described a surgical approach for the treatment of achalasia in 1913 [5,24]. The muscle fibers of the lower esophageal sphincter are incised without disrupting the mucosal lining of the esophagus. With the advancement of minimally invasive surgery and now peroral endoscopic myotomy, the open technique should rarely if ever be used. The thoracoscopic technique of myotomy for achalasia has also been replaced by the laparoscopic equivalent due to a higher incidence of postoperative reflux [15,25].

Laparoscopic technique — The following is a description of the key technical elements of performing a laparoscopic esophageal myotomy [1].

Patient position — Patients can be placed in a supine, split leg, or lithotomy position with padding, such as on a surgical bean bag. We prefer the split leg position for optimal ergonomics (surgeon stands between the legs) and access to the hiatus. The patient is positioned in a steep reverse Trendelenburg position, which allows the stomach and other organs to fall away from the esophageal hiatus.

Abdominal access and port placement — Abdominal access is obtained at the left upper quadrant just inferior to the costal margin by inserting a Veress needle followed by placement of an optical trocar after establishing pneumoperitoneum according to standard laparoscopic techniques. Four operative ports (two for the surgeon, one for the assistant, and one for the scope) are then placed under direct vision, and liver retraction is then achieved by any number of such devices on the market via an additional port site (figure 2). Other port configurations can also be used. (See "Abdominal access techniques used in laparoscopic surgery", section on 'Foregut surgery'.)

Mobilization of the gastric fundus — Based on the surgeon's preference, the initial dissection can begin on the right or left side of the esophageal hiatus. The steps to mobilize the gastric fundus include:

●Dividing the left phrenogastric ligaments by dividing the short gastric arteries, starting at the inferior pole of the spleen to the exposed left crus of the diaphragm.

●Incising the gastrohepatic ligament in an avascular plane.

●Preserving the nerve of Latarjet and avoiding injury to an accessory or replaced hepatic artery.

●Dividing the right anterior phrenoesophageal ligament and the peritoneum overlying the anterior abdominal esophagus.

●Preserving the anterior vagus nerve, which lies immediately posterior to the right anterior phrenoesophageal ligament.

●At this point, if a posterior partial (Toupet) fundoplication is performed, a posterior esophageal window is created. In creating this window, the posterior vagus nerve is identified and protected. If an anterior fundoplication (Dor) technique is used, a posterior esophageal window is unnecessary unless a hiatal hernia and/or a relatively short esophagus is encountered and there is a need for further mobilization to allow more intra-abdominal length in order to construct a proper fundoplication. (See 'Fundoplication' below and 'Role of a fundoplication' below.)  

Mobilization of the mediastinal esophagus — The distal portion of the mediastinal esophagus is mobilized to achieve sufficient length to perform a myotomy incision that divides the entire length of the lower esophageal sphincter and permits a tension-free fundoplication. A Penrose drain may be placed around the gastroesophageal junction to facilitate retraction of the esophagus but is not essential, especially if an anterior fundoplication is to be performed.

Myotomy — It is critical when performing the myotomy that visualization and exposure are adequate to prevent inadvertent mucosal injuries. The cardioesophageal fat pad and the anterior vagus nerve must be cleared from the esophagus and the gastroesophageal junction. A continuous myotomy is performed for 6 cm on the esophagus and 3 cm onto the stomach. (See 'Extent of gastric myotomy' below.)

The following principles are important when performing the myotomy:

●A suitable and stable platform is useful. Our preference is a lighted bougie dilator (50 Fr), which illuminates the esophagus and stretches the muscle fibers around the gastroesophageal junction, facilitating their division. An endoscope may be used instead of the lighted bougie dilator. The anterior surface of the esophagus is completely exposed, and slight tension is created by retracting caudally with a Babcock retractor or similar instrument.

●The incision may be started on either the stomach or the esophagus. We prefer starting on the stomach; while this is a more difficult submucosal plane to identify, we find it easier to proceed in a cephalad than caudal direction.

The use of electrocautery should be avoided unless critical when creating the myotomy. If bleeding is encountered, it should be controlled with pressure and patience since thermal injury can lead to an unrecognized or delayed perforation of the esophagus.

●The myotomy is performed by individually dividing the esophageal and gastric muscle fibers.

•The longitudinal muscles are divided first, which exposes the underlying circular muscles.

•Division of the circular layer reveals a bulging mucosal plane that should appear smooth and white (picture 2).

•The most critical and challenging factor is to create a 3 cm myotomy caudal to the gastroesophageal junction, where the tissue plane becomes less readily identifiable. An intervening sling of muscle fibers may blur the dissection, and the stomach mucosa is thinner and more prone to perforation (figure 3).

•The portion of the myotomy on the esophagus and stomach should be 6 and 3 cm in length, respectively. Thus, the total length of the entire myotomy is 9 cm.

●Endoscopic inspection of the mucosa and the myotomy is performed prior to proceeding to the next steps to identify and repair any mucosal perforations.

Fundoplication — If a fundoplication procedure is performed, it is typically a partial (eg, Toupet or Dor) and not a circumferential (Nissen) wrap. A Toupet fundoplication is a 270° posterior wrap of the fundus around the esophagus, while the Dor fundoplication is a 180° anterior wrap. (See 'Role of a fundoplication' below.)

●If a Toupet (posterior) fundoplication is being performed, a retroesophageal window is established along the lines of dissection (figure 4 and picture 3). The following is a brief description of the technique:

•The fundus is mobilized by dividing the short gastric vessels and all fundal attachments starting approximately at the inferior pole of the spleen, approximately 10 to 15 cm inferior to the angle of His.

•The retroesophageal window is developed by further dissection along the base of the left crus.

•Following mobilization of the mediastinal esophagus, the gastroesophageal hiatus is closed posteriorly with interrupted sutures if a large defect is present, but our preference is to leave laxity of the hiatus.

•The posterior aspect of the gastric fundus is passed through the retroesophageal window and secured to the right edge of the myotomy and right crus of the diaphragm with a coronal suture. Another interrupted suture is placed to secure the posterior fundus to the base of the right crus.

•The leading posterior edge of the fundus is secured to the right edge of the myotomy with interrupted sutures.

•Any redundancy of the fundus is removed from behind the esophagus, and the proximal, anterior aspect of the fundus is secured to the left side in a similar fashion.

●A Dor (anterior) fundoplication may be particularly useful to buttress the repair of an esophageal perforation that may occur. The greater curve of the fundus is grasped and placed anteriorly to the right side of the gastroesophageal hiatus. The following is a brief description of the technique:

•An inner row of interrupted sutures is used to secure the medial aspect of the fundus to the left side of the myotomy, which begins to recreate the angle of His.

•The anterior fundus is folded over the esophagus, and a coronal suture to the right crus and right side of the esophagus is performed.

•A second row of interrupted sutures is placed to fix the leading edge to the right side of the myotomy (picture 4). A final suture from the apex of the gastroesophageal hiatus to the fundus completes the fundoplication.

Robotic technique — An alternative to laparoscopic surgical myotomy is robotic-assisted minimally invasive surgery [26]. A meta-analysis of several small comparative series reported that the outcomes of robotic Heller myotomy were similar to those of laparoscopic Heller myotomy except that the incidence of intraoperative esophageal perforation was much lower (odds ratio [OR] 0.13, 95% CI 0.04-0.45) [27]. A subsequent meta-analysis of nine comparative studies also reported significantly fewer esophageal perforations (OR 0.36, 95% CI 0.15-0.83), in addition to fewer reinterventions (OR 0.18, 95% CI 0.07-0.47) for the robotic approach. The laparoscopic approach, however, had significantly shorter operative times [28]. However, the quality of evidence remains low and randomized controlled trials are needed to properly compare the two techniques.

TECHNICAL VARIANCES OF SURGICAL MYOTOMY — 

There are several technical variations for performing a laparoscopic or robotic Heller myotomy, reflecting areas of controversy. These include the length of the gastric component of the myotomy incision, optimal type of antireflux procedure [29], and management of a sigmoid megaesophagus.

Extent of gastric myotomy — The traditional esophageal myotomy includes a 1.5 to 2 cm extension of the incision onto the cardia of the stomach [30-32]. We perform an extended gastric myotomy, which is defined as a 3 cm myotomy incision onto the cardia of the stomach [33]. A 3 cm extension of the esophageal anterior myotomy incision onto the stomach provides long-term durable dysphagia relief due to disruption of both the clasp (semicircular) and sling (oblique) fibers [29-31]. The importance of the gastric sling fibers in the lower esophageal sphincter (LES) mechanism was recognized when transitioning from the thoracoscopic to laparoscopic approach (figure 3) [14].

A case series from a prospective database found that symptoms following the laparoscopic Heller myotomy were improved with an extended gastric myotomy [30]. Patients treated with a 3 cm extended gastric myotomy (n = 58) and a Toupet fundoplication had a significantly lower LES pressure (9.5 versus 15.8 mmHg), less frequent dysphagia (1.2 versus 2.1 percent), less severe dysphagia on visual analog scale pain score (3.2 versus 5.3), and fewer recurrences requiring dilatation (two versus nine patients) compared with patients treated with a standard 1.5 cm gastric myotomy and a Dor fundoplication (n = 52). Patients treated with the extended gastric myotomy had similar rates of heartburn (1.3 versus 1.7 percent), regurgitation (0.3 versus 0.8 percent), chest pain (0.3 versus 0.6 percent), and proximal (1.7 versus 2.3 percent) and distal (6.0 versus 5.9 percent) esophageal acid exposure. Up to a median follow-up of 63±10 months, there was no significant change over time in dysphagia severity for patients who underwent extended myotomy [31].

Role of a fundoplication — A fundoplication is included in most patients undergoing a laparoscopic or robotic myotomy. Both anterior (Dor) and posterior (Toupet) partial fundoplication techniques are used, neither increases the risk of postoperative dysphagia [34], and currently, there is no consensus on which procedure is superior:

●The Dor procedure avoids mobilization of the stomach during the initial dissection and is technically easier to perform. In addition, it is a useful technique to buttress the repair of an inadvertent esophageal perforation.

●The Toupet fundoplication splays the edges of the myotomy, which may decrease fibrosis at the incision site and reduce recurrence of dysphagia.

The Toupet and Dor fundoplications have been directly compared in the context of Heller myotomy [35-37]. No difference was found in either efficacy or complications [38]. Thus, the choice can be made based patient anatomy and surgeon training/preference.

Authors of this topic prefer to perform a Toupet partial fundoplication as we believe it reduces the risk of recurrent dysphagia by splaying open the edges of the myotomy, thus preventing scarring. In addition, it is a better antireflux procedure [39]. We only perform a Dor fundoplication to provide coverage of the primary repair when there is an esophageal perforation [40]. A circumferential complete fundoplication (Nissen) is usually not performed to avoid excessive constriction at the gastroesophageal junction. Nissen fundoplication has been shown to increase the risk of severe postoperative dysphagia [34,41].

While a fundoplication is routinely performed with a laparoscopic or robotic myotomy, there are several instances when a fundoplication is not performed. These settings include:

●The myotomy is performed with a left video-assisted thorascopic surgery approach without disruption of the phrenoesophageal ligament [42].

●Late-stage disease manifested by the presence of a sigmoid megaesophagus on the preoperative esophagogram. (See 'Sigmoid megaesophagus' below.)

Sigmoid megaesophagus — Sigmoid megaesophagus is an enlarged and atonic esophagus that results from long-standing increased LES pressure. Traditionally, a standard Heller myotomy was not performed on patients with a sigmoid megaesophagus, as the degree of esophageal dilation and relief of symptoms were not thought to improve with myotomy [43]. Hence, patients with a sigmoid esophagus were typically treated with an esophagectomy prior to the laparoscopic era [44]. However, esophagectomy is a morbid procedure. With the advent of minimally invasive Heller myotomy, the procedure is increasingly performed in patients with late-stage achalasia with varying, but generally positive, results:

●A review of 113 consecutive patients with achalasia who were treated with a laparoscopic Heller myotomy and Dor fundoplication [43]. The 12 patients with a sigmoid megaesophagus had an equivalent operating time, length of hospital stay, rate of postoperative complications, and relief of symptoms compared with patients without esophageal dilatation.

●A review of 51 patients with achalasia treated with a Heller myotomy and Dor fundoplication by laparoscopy or laparotomy found that the 14 patients with a sigmoid megaesophagus had postoperative changes in esophageal width, LES pressure, dysphagia score, and regurgitation score equivalent to those of the 37 patients without a megaesophagus [45].

●In contrast to the previous two studies, a retrospective review of 394 patients with achalasia undergoing a laparoscopic Heller myotomy found that sigmoid megaesophagus was an independent predictor for failure of a laparoscopic myotomy as the primary or secondary treatment of achalasia [46]. There were 13 patients with a megaesophagus in this study: five had a good outcome, and eight patients were considered surgical failures.

Currently, the majority of surgeons will initially offer patients with a sigmoid megaesophagus a minimally invasive Heller myotomy and, if this fails, a subsequent esophagectomy [47,48]. If a Heller myotomy is performed in patients with a sigmoid megaesophagus, one should be careful if adding a concomitant partial fundoplication, which has the potential to cause angulation and/or resistance in a megaesophagus. However, there are no short- or long-term studies on the efficacy of this procedure to improve symptoms and no high-quality data from randomized trials to suggest the best operative approach for management of sigmoid megaesophagus.

POSTOPERATIVE MANAGEMENT — 

The principal components of postoperative care for surgical myotomy include advancement of diet and control of nausea. The following is a summary of the major issues:

●While some advocate performing an upper gastrointestinal series prior to initiating a diet, we find this unnecessary if there has been good intraoperative visualization of the esophagus and stomach as well as intraoperative endoscopy. However, one should have a low threshold for obtaining an upper gastrointestinal series if a patient develops symptoms and signs suggestive of an esophageal or gastric perforation (eg, chest pain, epigastric pain, fever, tachycardia, subcutaneous or mediastinal emphysema, and/or otherwise unexplained leukocytosis).

●Clear liquids are typically started the night of the procedure following minimally invasive surgery. If no dysphagia occurs, the diet is advanced to a soft diet the following day. If episodes of dysphagia occur, patients are maintained on a full liquid diet for a longer period of time prior to advancing the diet.

●Aggressive treatment with antiemetics is provided for patients complaining of nausea to avoid emesis, which can lead to rupture of the repair. Medications can be administered in a crushed form until the patient is tolerating a regular diet.

●In patients undergoing Heller myotomy with partial fundoplication, antacids or proton pump inhibitors are used only if patients experience symptoms of heartburn and regurgitation and a pH monitoring study reveals gastroesophageal reflux. Antacids or proton pump inhibitors are typically recommended for patients undergoing a Heller myotomy alone. (See 'Role of a fundoplication' above.)

It should be noted that, in treated achalasia patients with acid reflux, the symptom correlation to abnormal pH study is unreliable, making objective postoperative testing important. The nuances relevant to accurate diagnosis of gastroesophageal reflux in such patients must be considered [49].

COMPLICATIONS — 

Following laparoscopic or robotic Heller myotomy, the morbidity rate ranges between 1 and 10 percent and the mortality rate is <0.1 percent in the 30-day perioperative period [28,31,46,50-56].

Intraoperative complications — The major intraoperative complications include perforation of the esophageal or gastric mucosa, pneumothorax, division or injury to the anterior vagus nerve, and splenic injury.

●Perforation – The risk of an esophageal or gastric perforation during surgical myotomy ranges from 10 to 16 percent [42,57]. Mucosal perforations are repaired with fine 4-0 and 5-0 absorbable monofilament suture. An advantage of the anterior (Dor) fundoplication is that it will buttress the repair.

●Pneumothorax – A pneumothorax can be caused by inadvertent injury to the pleura during mobilization of the mediastinal esophagus. If this occurs, the defect can be repaired with a primary suture closure or by inserting a chest drain if the patient develops intraoperative hypotension or hypoxia. Otherwise, neither a primary repair nor a chest tube is necessary in most patients.

●Division of vagus nerve – Using careful dissection and attention to detail, injury to the vagus nerves is rare. The anterior vagus nerve is at risk of injury during several technical steps of the operation, including the initial dissection of the esophagus, mobilizing the gastroesophageal fat pad, performing the myotomy, and performing the fundoplication [58]. The posterior vagus nerve is less likely to be injured. If an injury to only the anterior or posterior vagus nerve occurs, it is not repaired, as postvagotomy diarrhea, bloating, early satiety, and/or dumping syndrome rarely occur with a unilateral vagotomy [59]. Nevertheless, extra care should be taken to identify and preserve both nerves.

●Splenic injury – The risk of injury to the spleen ranges from <1 to 5 percent [60-62]. The higher rates are from reports when laparoscopic surgery was in the early stages of use. Management of an intraoperative splenic injury is discussed elsewhere. (See "Management of intra-abdominal, pelvic, and genitourinary complications of colorectal surgery", section on 'Splenic injury'.)

Postoperative complications — The most common complications following surgical myotomy with a fundoplication include perforation, recurrent dysphagia, and gastroesophageal reflux.

Perforation — The most common early postoperative complication is gastric or esophageal perforation, which occurs in 1 to 7 percent of patients [31,46,50-52]. Late perforations usually result from either direct mucosal injury that is not recognized during surgery or inadvertent thermal injury usually from misuse of electrocautery during myotomy. Perforations usually result in diffuse peritonitis and/or mediastinitis and may be life-threatening [63].

If a perforation is suspected, a water-soluble contrast radiograph should be obtained. Management of a late perforation requires diversion and a gastrostomy tube or an esophagectomy. (See "Esophageal perforation".)

Recurrent dysphagia — The Heller myotomy with a fundoplication results in effective symptom control in 90 to 97 percent of patients [42,46]. However, recurrent dysphagia is a late complication of a Heller myotomy and fundoplication. It can occur in approximately 3 to 10 percent of patients undergoing a Heller myotomy, with the onset of symptoms six months or later after surgery [31,46,51,64,65].

The most common cause is gastroesophageal reflux disease (GERD), which will cause inflammation or even a stricture in the distal esophagus. For GERD-related recurrent dysphagia, the first step should be to start acid suppression with a proton pump inhibitor and perform an endoscopy with dilation if a stricture is present. (See 'Gastroesophageal reflux' below.)

The next most common cause is an incomplete myotomy. This can occur with incomplete division of the clasp (semicircular) fibers on the esophagus or failure to divide the sling (oblique) fibers on the stomach at least 3 cm below the gastroesophageal junction. This was more common in patients who were managed with a thoracoscopic approach to myotomy [32]. In some cases, the incision was suboptimal, even with the laparoscopic approach; as a result, a repeat procedure may be warranted to extend the incision further into the stomach [30,31]. Other potential reasons for recurrent dysphagia include:

●Herniated fundoplication

●Scarring

●Peptic stricture

●Obstructing tumors

The approach to the patient with recurrent dysphagia is to identify the cause and rule out significant pathology, such as a malignancy, stricture, or hernia. The diagnostic evaluation typically begins with upper endoscopy or, if endoscopy is not available, a barium swallow. Manometry may be performed if recurrent achalasia is a possible cause of the dysphagia. (See "Approach to the evaluation of dysphagia in adults" and "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'Diagnostic evaluation'.)

For patients with persistent or recurrent symptoms of dysphagia after a surgical myotomy, surgical options include pneumatic dilation, peroral endoscopy myotomy (POEM), or redo laparoscopic or robotic surgical myotomy. The choice should be determined for individual patients [16]. Fit patients who have signs of late-stage achalasia (sigmoid megaesophagus) may require esophagectomy. (See 'Sigmoid megaesophagus' above.)

Gastroesophageal reflux — The rate of GERD developing in patients undergoing surgical myotomy with a partial fundoplication (Dor or Toupet) ranges from 2 to 26 percent in different series [29,31,66-68]. The rate of GERD for patients undergoing myotomy alone is much higher. This was demonstrated in a prospective randomized trial of 43 patients with achalasia in which patients undergoing a Heller myotomy with a Dor fundoplication had a significantly lower rate of pathologic GERD at six months after surgery compared with patients undergoing a Heller myotomy without a fundoplication (9 versus 48 percent) [29]. Thus, laparoscopic or robotic Heller myotomy is usually performed with a partial fundoplication. (See 'Role of a fundoplication' above.)

However, other myotomy procedures, including pneumatic dilation, POEM, and thoracoscopic myotomy, are performed without a fundoplication. As expected, the postoperative GERD rate is much higher after those procedures. As an example, a meta-analysis found that the incidence of GERD measured by pH analysis was 47 percent after POEM compared with 11 percent after laparoscopic Heller myotomy with fundoplication [69].

As mentioned, a common presentation of GERD in achalasia patients after myotomy is dysphagia. Patients should have pH monitoring performed three to six months after myotomy to search for asymptomatic GERD and repeated with any change in symptoms that could suggest GERD, especially heartburn and regurgitation. Patients with abnormal esophageal acid exposure are treated medically. Incomplete myotomy with stasis in the distal esophagus can mimic GERD. (See "Initial management of gastroesophageal reflux disease in adults".)

Other complications — Pneumothorax, bleeding, inadvertent vagal injury, and infection are uncommon complications, with at least one occurring in approximately 3 percent of cases [70].

RISK OF ESOPHAGEAL CANCER — 

Untreated achalasia is associated with an increased risk of squamous cell esophageal cancer. There is a paucity of long-term data on the development of esophageal cancer following a myotomy. In a retrospective review of 226 patients surgically treated for achalasia, four (1.8 percent) developed a squamous cell carcinoma at 2, 8, 13, and 18 years after the operation [68]. The risk of esophageal cancer in patients with achalasia and the possible role of screening are discussed separately. (See "Achalasia: Pathogenesis, clinical manifestations, and diagnosis", section on 'Natural history and prognosis'.)

Patients who have gastroesophageal reflux disease after treatment for achalasia could develop Barrett esophagus [71-73]. Thus, it is important to correctly identify such patients and initiate appropriate treatment and regular endoscopic surveillance for their acid reflux [74]. (See 'Gastroesophageal reflux' above.)

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Achalasia".)

SUMMARY AND RECOMMENDATIONS

●Treatment goal and methods – The primary goal of the operative treatment of achalasia is to relieve the functional obstruction of the lower esophageal sphincter (LES) while preventing reflux. Myotomy of the LES can be accomplished with either pneumatic dilation or endoscopic (peroral endoscopy myotomy [POEM]) or surgical myotomy. The laparoscopic or robotic Heller myotomy with a partial fundoplication is an excellent surgical treatment of achalasia, with effective control of symptoms in 90 to 97 percent of patients. (See 'Evaluation of myotomy as a treatment for achalasia' above.)

●Surgical myotomy – It is critical when performing the myotomy that visualization and exposure are adequate to prevent inadvertent mucosal injuries. A continuous myotomy is performed for 6 cm up the esophagus and 3 cm onto the stomach as measured from the gastroesophageal junction.

We suggest an extended (3 cm) rather than a traditional (1.5 cm) gastric myotomy (Grade 2C). An extended myotomy reduces the rate of recurrent dysphagia by dividing both clasp and sling fibers. (See 'Surgical myotomy' above and 'Extent of gastric myotomy' above.)

●Fundoplication – For patients without a megaesophagus, we suggest performing a partial fundoplication with laparoscopic or robotic myotomy (Grade 2C). Compared with myotomy procedures without a fundoplication (pneumatic dilation, POEM, thoracoscopic myotomy), fundoplication reduces the rate of postoperative gastroesophageal reflux disease (GERD). (See 'Gastroesophageal reflux' above.)

For most patients, we suggest performing a Toupet partial fundoplication (270° posterior wrap of the fundus around the esophagus) (Grade 2C). We believe that it reduces the risk of recurrent dysphagia by splaying open the edges of the myotomy, thus preventing scarring. We perform a Dor fundoplication (180° anterior wrap) to provide coverage of the primary repair only when there is an esophageal perforation. However, there is no consensus on which procedure is superior. (See 'Fundoplication' above and 'Role of a fundoplication' above.)

●Sigmoid megaesophagus – For patients with a sigmoid megaesophagus due to late-stage achalasia, we suggest first performing a laparoscopic or robotic Heller myotomy because of the lower morbidity (Grade 2C). In such patients, Heller myotomy should not be performed with a fundoplication as this is more likely to cause angulation and/or resistance to a very abnormal esophagus. Those who do not respond may require esophagectomy. (See 'Sigmoid megaesophagus' above.)

●Complications

•Intraoperative complications – The major intraoperative risks include perforation of the esophageal or gastric mucosa, pneumothorax, division or injury to the anterior vagus nerve, and splenic injury. (See 'Intraoperative complications' above.)

•Postoperative complications – The major postoperative complications include esophageal or gastric perforation (1 to 7 percent), recurrent dysphagia (3 to 10 percent), and gastroesophageal reflux (2 to 26 percent). (See 'Complications' above.)