Endoscopic Versus Robotic Myotomy for Treatment of Achalasia

Achalasia is a primary esophageal motor disorder of unknown etiology characterized by degeneration of the myenteric plexus, resulting in impaired relaxation of esophagogastric junction (EGJ), along with loss of peristalsis in the esophageal body. The standard criteria for diagnosing achalasia is high-resolution esophageal manometry, which shows incomplete relaxation of the EGJ along with absence of esophageal body peristalsis. These anomalies usually cause dysphagia and regurgitation as the main symptoms. Three subtypes of achalasia have been defined based on the findings of high-resolution manometry in the esophageal body: type I or classic achalasia with low intraesophageal pressure, type II with panesophageal pressurization, and type III with high-amplitude spastic contractions.

Different treatment options have been described for this pathology, with pneumatic dilation (PD) and myotomy being considered first-line, whether surgical (laparoscopic Heller myotomy, LHM) or endoscopic (peroral endoscopic myotomy, POEM). PD is the most frequently performed treatment worldwide with a reported long-term effectiveness between 50-93%, although it is generally a procedure that requires multiple sessions. On the other hand, LHM combined with an antireflux procedure is a treatment that, despite being more invasive, in most cases requires only one treatment session and offers success rates of 71% to 92%. POEM is a recently emerging procedure but with a success rate in prospective cohorts that sometimes exceeds 90%.

Multiple studies have shown that treatment outcomes depend on the subtype of achalasia. Based on available data, pneumatic dilation, laparoscopic Heller myotomy and POEM are believed to be effective for achalasia type I and II, while POEM has emerged as the preferred treatment for achalasia type III, which is believed to be related to the ability to perform a proximal extended myotomy. The arrival of POEM as a less invasive alternative for the treatment of achalasia has revolutionized expectations to the point that it has become a routine procedure in many centers around the world that use it for the treatment of any type of achalasia. In recent years, there is a large amount of data examining the effectiveness of POEM, including several meta-analyses. The success rate of POEM in prospective cohorts has been greater than 90% and has been maintained across all achalasia subtypes. Two randomized studies have been published comparing POEM with LHM, providing a framework to evaluate the comparative efficacy and safety of these two interventions and to determine which should be first-line for the treatment of these patients. With these data, it seems that the two procedures offer the same clinical results in the medium term.

However, the main issue that POEM faces is the presence of post-procedure reflux. The incidence of reflux disease seems to be significantly higher after POEM compared to LHM with fundoplication but the way to evaluate the presence of reflux in these patients is variable between studies and it seems that this incidence could decrease one year after the procedure.

In recent years, there has been a growing expansion of the application of robot-assisted technology. Robotic Heller myotomy (RHM) has been proposed as an alternative minimally invasive approach to traditional laparoscopy. However, there are doubts regarding the increased cost, longer surgical times, and loss of tactile feedback associated with the robotic approach. A recent systematic review proposes it as an alternative with comparable results to conventional laparoscopy in terms of clinical results and associated morbidity and mortality. Furthermore, it seems that the robotic approach offers a decrease in the rate of mucosal perforation during the procedure that could be related to the greater precision that this technique offers in the dissection of the muscular layer, which ranges between 0-1% and is comparable to that offered by the POEM but lower than the LHM.

Therefore, POEM and RHM could have comparable results in short term, but there is no clear certainty about the results in medium-long term. Likewise, there is a lack of studies that confirm postoperative reflux results in both procedures.

The purpose of the study is evaluate the clinical and quality of life results of RHM and compare them with the results of POEM in the treatment of achalasia.

Inclusion criteria

• Patients with symptomatic achalasia with an Eckardt score of > 3 and pre-op barium swallow, manometry and esophagogastroduodenoscopy consistent with the diagnosis
• Persons of age > 18 years with medical indication for surgical myotomy or EBD
• Signed written Informed Consent

Exclusion criteria

• Patients with previous surgery of the stomach or esophagus
• Patients with known coagulopathy
• Previous myotomy
• Patients with liver cirrhosis and/or esophageal varices
• Malignant esophageal lesion
• Hiatal hernia
• Extensive dilatation of the esophagus