In 1914, Ernest Heller described the first cardiomyotomy for the treatment of achalasia.1 He described an anterior and posterior myotomy along the gastroesophageal junction (GEJ) using a thoracoabdominal incision. The operation was subsequently modified by Groenveldt and Zaaijer to include only the anterior myotomy. Owing to the morbidity of the open approach, this operation was performed primarily in patients who failed medical management. It was not until the early 1990s with the advent of minimally invasive techniques that minimally invasive esophagocardiomyotomy became a viable first-line therapy. This operation has yielded excellent results, with 90% to 95% of patients receiving durable relief of dysphagia.2–5 At the University of Washington, we converted from a thoracoscopic approach to a laparoscopic Heller myotomy in 1994, and along with most centers, we now consider laparoscopic esophageal myotomy to be an excellent first-line therapy because of the low morbidity, durability, and the high levels of success after minimally invasive esophagocardiomyotomy.3,6–9
Achalasia is characterized by aperistalsis of the mid-to-distal esophageal body combined with lack of LES relaxation. Although it is the most common primary esophageal motility disorder, it is rare. The reported incidence in North America is 0.5 to 1 per 100,000 people. Achalasia was first described as cardiospasm in the 17th century by Sir Thomas Willis. The name achalasia, meaning “failure to relax,” was coined by Lendrum in 1937.10
Achalasia manifests most commonly with progressive dysphagia, starting with solids and progressing to liquids. The diagnosis usually is made between the ages of 20 and 50 years without a gender predilection. Ineffective relaxation of the LES and loss of esophageal peristalsis lead to impaired emptying and gradual esophageal dilatation, resulting in severe dysphagia. Patients may use various maneuvers to attempt to clear the esophagus, including drinking liquids, standing after swallowing, walking around during meals, raising hands over head, and extending or flexing the neck. Patients also may complain of regurgitation of undigested food, cough, aspiration, wheezing, and choking. These symptoms often are made worse in the recumbent position, when esophageal contents flow back into the airway, and in some can lead to recurrent aspiration pneumonia.
Chest pain is commonly reported, and it is postulated to be a result of esophageal overdistention and uncoordinated peristalsis. Stress or cold liquids can also exacerbate these symptoms in some. A subset of patients with simultaneous contractions of normal or near-normal amplitude on manometry, are considered to have a variation of Achalasia termed vigorous achalasia.11 In reality, achalasia may be a heterogeneous collection of disorders or subtypes as has been recently described by Pandolfino et al.12 As with other hypercontractile esophageal motility disorders, simultaneous contractions are postulated as one cause of chest pain, but this seems unlikely for most patients with achalasia who demonstrate little even simultaneous contractile activity. Heartburn may occur but is usually the result of fermentation of unevacuated food in the esophagus and not gastroesophageal reflux disease (GERD). Misdiagnosis with GERD or the presence of aspiration pneumonia can lead to a delay in treatment.
Mild weight loss is occasionally a manifestation of the disease. Rapid or significant drop in weight of more than 10 lb (4 kg) along with advanced age (>60 years) or rapid onset of symptoms (<6 months) should alert clinicians to the possibility of an esophageal malignancy that has caused obstruction (and with it all the other manifestations of achalasia). This entity is often referred to as pseudoachalasia. If any diagnostic doubt exists, CT should be considered. Alternatively, if available, esophagogastroscopy combined with endoscopic ultrasound is a highly specific and sensitive method of confirming or excluding tumors and can be used to simultaneously biopsy suspicious masses or lymph nodes.
Until the early 1990s surgical myotomy was accomplished via open transthoracic or transabdominal approach, both of which were associated with the morbidity and mortality of a major open operation. Since the introduction of minimally invasive surgery for the treatment of achalasia the use of Heller myotomy has expanded, and it has become an attractive first option as a result of its improved overall risk-benefit ratio.
The laparoscopic approach has been demonstrated to be superior to both open and thoracoscopic procedures with respect to complications, morbidity, mortality, relief from dysphagia, prevention of postoperative reflux, operative times, and hospital stay.11,13 Additional advantages of the laparoscopic approach include improved visualization of the esophageal muscle layers, better access to perform a longer gastric myotomy owing to improved esophageal and gastric access, substantial reduction in postoperative pain, and ease of performing an antireflux procedure.
As previously mentioned, the laparoscopic approach to Heller myotomy has been our preferred method since 1994. We found that the limited gastric myotomy (0.5–1.0 cm) afforded by the thoracoscopic approach did not protect patients from gastroesophageal reflux, and in fact, pH monitoring revealed that 80% of patients had pathologic reflux. In our experience with the thoracoscopic approach we also found that 17% of patients returned with recurrent dysphagia, half of which required a laparoscopic revision of the myotomy with extension onto the stomach. The laparoscopic approach permitted a long esophageal myotomy that could be extended onto the stomach.
In our initial experience with the laparoscopic approach we performed a traditional 1 to 2 cm gastric myotomy, and the majority of patients showed excellent improvement in their dysphagia. Still, there were some with recurrent dysphagia that needed an operative revision, and we noted that extending the gastric portion of the myotomy improved their symptoms.6 Therefore, in 1998, we began extending the myotomy to a full 3 cm on the gastric side and also began performing a Toupet rather than a Dor fundoplication.14 We reasoned that an anterior fundoplication would be more difficult with a 3-cm cardiomyotomy and suspected that the posterior Toupet would provide better control of reflux.
Subsequently, Di Martino et al.15 found similar results using an animal model. They performed a 6-cm myotomy with a 3-cm gastric extension which thus disrupted the sling fibers of the stomach and led to a more effective ablation of the LES on manometry. We have found that dysphagia was both less frequent (once a month vs. once a week on average) and less severe (3.2 vs. 5.3 on a 10-point visual analog scale) in the extended myotomy with Toupet fundoplication group. Perhaps most importantly, no patient has required surgical intervention for recurrent dysphagia in the last 13 years in our center. The need for endoscopic treatment was also rare.14 We also found that completely obliterating the LES did not result in more reflux long-term because the mean distal esophageal acid exposure was equivalent between the two groups (extended myotomy with Toupet fundoplication 6.3% vs. shorter myotomy with Dor fundoplication 3.5%).
Whether to perform an antireflux procedure is no longer controversial and is accepted by most surgeons. It is also uniformly accepted as good practice, and has been validated by a randomized trial, that a partial fundoplication provides better control of reflux without adversely affecting the relief of dysphagia.16 In their study, Richards and colleagues enrolled 43 patients to either undergo Heller myotomy with Dor fundoplication versus Heller myotomy alone and found pathologic gastroesophageal reflux in 9.1% versus 47.6% of patients respectively. They also noted that there was no negative effect on relief of dysphagia.
Which antireflux procedure to perform does remain a matter of debate. Reported results of postoperative reflux after esophageal myotomy with Dor fundoplication range from 4% to 25%.16,17 Several studies support use of the Toupet fundoplication, reporting similarly successful results.18,19 A recent multicenter randomized trial comparing laparoscopic Dor versus Toupet fundoplication following Heller myotomy showed that there was no difference in esophageal symptoms between the two groups.19 There was a trend toward higher percentage of abnormal 24-hour pH-test results in the Dor group (41.7% vs. 21.0%); however, this was not statistically significant.
Most surgeons find that performing an antireflux procedure whether it be Dor or Toupet fundoplication in conjunction with laparoscopic myotomy does not add significant time or morbidity to the operation and is not associated with increased postoperative dysphagia. We find that the Toupet fundoplication provides an effective barrier to reflux as well as possibly preventing scarring and reapproximation of the divided muscle edges. However, the proponents of the Dor like the fact that it covers the mucosa of the myotomy and might be protective if there is an injury. Also, a Dor does not require posterior esophageal mobilization or division of the short gastric vessels. A total fundoplication for the most part is not used as it results in a high incidence of recurrent dysphagia when compared to a partial fundoplication.20
Recently, robotic assisted Heller myotomy has emerged as a safe alternative to the laparoscopic approach. Some believe that robotics improves visualization, degree of instrument freedom, and tremor control. Three retrospective studies exist comparing robotic versus laparoscopic Heller myotomy.21–23 All of these studies show no intraoperative perforations with the robotic approach, an 8% to 16% perforation rate with the laparoscopic approach, and no differences in postoperative dysphagia. The information that can be extrapolated from these studies is limited, however, since they were not randomized, the groups were heterogeneous, and the operations were performed at different times within each group’s operative experience, and in some cases in different groups altogether.
In our experience using both the laparoscopic and robotic approaches, we have found that the laparoscopic approach yields excellent outcomes with low intraoperative perforation rates. The robotic approach does provide the “feeling” of more precision, and may indeed be beneficial for surgeons with less experience. Whether this is worth the added cost and time associated with the robotic approach is open for debate.
Before the development of laparoscopic techniques in the early 1990s, the first-line therapy for achalasia was endoscopic dilation. The concept of dilating the LES to provide relief for patients with achalasia was first performed in the 17th century by Sir Thomas Willis when he used a whalebone to perform a dilation. Today, endoscopic techniques such as pneumatic dilation and endoscopic administration of botulinum toxin are still used by some as first-line treatments before surgery. However, the low morbidity and long durability of laparoscopic esophageal myotomy is making laparoscopic Heller myotomy a more attractive first-line therapy.
More recent advances in therapeutic endoscopy have led some surgeons to begin performing endoscopic esophageal myotomy. These procedures are termed peroral esophageal myotomy (POEM).24,25 Using an endoscope, an 8-cm esophagogastric myotomy of the circular muscle fibers is performed via a submucosal tunnel after an incision is made in the mucosa of the midesophagus. The longitudinal muscle fibers are left intact and the mucosa is closed on the way out. Initial reports with regard to dysphagia have been promising; however, further longer-term studies are needed to better elucidate the efficacy and complication profile of this procedure. Specifically, it is unclear whether relief of dysphagia is equivalent when only the circular muscle fibers are divided, and we do not know if gastroesophageal reflux is more frequent since a fundoplication cannot be performed. The adaptation of this technique for long myotomies is discussed in Chapter 35.
