Research gap in esophageal achalasia: a narrative review

In recent years, new translational evidence, diagnostic techniques, and innovative therapies have shed new light on esophageal achalasia and revamped the attention on this relatively rare motility disorder. This narrative review aims to highlight the most recent progress and the areas where further research is needed. The four senior authors identified five topics commonly discussed in achalasia management: i.e. pathogenesis, role of functional lumen imaging probe in the diagnostic flow chart of achalasia, how to define the outcome of achalasia treatments, how to manage persistent chest pain after the treatment, and if achalasia patients' may benefit from a regular follow-up. We searched the bibliographic databases to identify systematic reviews, meta-analyses, randomized control trials, and original research articles in English up to December 2023. We provide a summary with the most recent findings in each of the five topics and the critical points where to address future research, such as the immune-genetic patterns of achalasia that might explain the transition among the different phenotypes, the need for a validated clinical definition of treatment success, the use of neuromodulators to manage chest pain, and the need for identifying achalasia patients at risk for cancer and who may benefit of long-term follow-up. Although undoubtedly, progress has been made on the definition and management of achalasia, unmet needs remain. Debated aspects range from mechanistic insights, symptoms, objective measure relationships, and accurate clinical responses to therapeutic interventions. Translational research is eagerly awaited to answer these unresolved questions.

Outcomes of Heller Myotomy for Esophageal Achalasia: Lessons From a 48-Year Prospective Experience With 4 Different Techniques

OBJECTIVE

To provide information on long-term outcomes of Heller myotomy for esophageal achalasia with or without an antireflux fundoplication.

BACKGROUND

Since the adoption of the Heller myotomy, surgeons have modified the original technique in order to balance the cure of dysphagia and the consequent cardial incontinence.

METHODS

Totally, 470 patients underwent primary Heller myotomy between 1955 and 2020. A long abdominal myotomy (AM) was performed in 83 patients, the Ellis limited transthoracic myotomy (TM) in 30, the laparotomic Heller-Dor (L-HD) in 202, the videolaparoscopic Heller-Dor (VL-HD) in 155. The HD was performed under intraoperative manometric assessment. Starting on 1973 these patients underwent a prospective follow-up program of timed lifelong clinical, radiological, endoscopic evaluations.

RESULTS

Median follow-up time was 23.06 years [interquantile range (IQR): 15.04-32.06] for AM, 29.22 years (IQR: 13.46-40.17) for TM, 14.85 years (IQR: 11.05-21.56) for L-HD and 7.51 years (IQR: 3.25-9.60) for VL-HD. In AM, relapse of dysphagia occurred in 25/71 (35.21%), in TM in 11/30 (36.66%), in LH-D in 10/201 (4.97%), in VL-HD in 3/155 (1.93%). Erosive-ulcerative esophagitis was diagnosed for AM in 28.16%, for TM in 30%, for L-HD in 8.45%, for VL-HD in 2.58%. Overall, the outcome was satisfactory in 52.11% for AM, 41.9% for TM, 89.05% for L-HD, 96.12% for VL-HD.

CONCLUSIONS

The Dor fundoplication drastically reduces postmyotomy gastroesophageal reflux. The Heller-Dor operation is a competitive option for the cure of esophageal achalasia if this operation is performed according to the rules of surgical physiology learned by means of intraoperative manometry.

Achalasia

Achalasia is a rare disorder of the oesophageal smooth muscle characterized by impaired relaxation of the lower oesophageal sphincter (LES) and absent or spastic contractions in the oesophageal body. The key pathophysiological mechanism is loss of inhibitory nerve function that probably results from an autoimmune attack targeting oesophageal myenteric nerves through cell-mediated and, possibly, antibody-mediated mechanisms. Achalasia incidence and prevalence increase with age, but the disorder can affect all ages and both sexes. Cardinal symptoms consist of dysphagia, regurgitation, chest pain and weight loss. Several years can pass between symptom onset and an achalasia diagnosis. Evaluation starts with endoscopy to rule out structural causes, followed by high-resolution manometry and/or barium radiography. Functional lumen imaging probe can provide complementary evidence. Achalasia subtypes have management and prognostic implications. Although symptom questionnaires are not useful for diagnosis, the Eckardt score is a simple symptom scoring scale that helps to quantify symptom response to therapy. Oral pharmacotherapy is not particularly effective. Botulinum toxin injection into the LES can temporize symptoms and function as a bridge to definitive therapy. Pneumatic dilation, per-oral endoscopic myotomy and laparoscopic Heller myotomy can provide durable symptom benefit. End-stage achalasia with a dilated, non-functioning oesophagus may require oesophagectomy or enteral feeding into the stomach. Long-term complications can, rarely, include oesophageal cancer, but surveillance recommendations have not been established.

Quality of Life After Operation for End-Stage Achalasia: Pull-Down Heller-Dor Versus Esophagectomy

BACKGROUND

Therapy for end-stage achalasia is debated, and data on long-term functional results of myotomy and esophagectomy are lacking. We compared quality of life and objective outcomes after pull-down Heller-Dor and esophagectomy.

METHODS

The study included 32 patients, aged 57 years (interquartile range [IQR], 49-70 years), who underwent the Heller-Dor operation with verticalization of the distal esophagus in case of first instance treatment or failed surgery caused by insufficient myotomy, and 16 patients, aged 58 years (IQR, 49-67 years; P = .806), who underwent esophagectomy after failed surgery for other causes. Data were extracted from a database designed for prospective clinical research. Postoperative dysphagia, reflux symptoms, and endoscopic esophagitis were graded by semiquantitative scales. Quality of life was assessed with the 36-Item Short Form Health Survey questionnaire.

RESULTS

The median follow-up period was 68 months (IQR, 40.43-94.48 months) after pull-down Heller-Dor and 61 months (IQR 43.72-181.43 months) after esophagectomy (P = .598). No statistically significant differences were observed for dysphagia (P = .948), reflux symptoms (P = .186), or esophagitis (P = .253). No statistically significant differences were observed in the domains physical functioning (P = .092), bodily pain (P = .075) or general health (P = .453). Significant differences were observed in favor of pull-down Heller-Dor for the domains role physical (100 vs 100, P = .043), role emotional (100 vs 0, P = .002), vitality (90 vs 55, P< .001), mental health (92 vs 68, P = .002), and social functioning (100 v s75, P = .011).

CONCLUSIONS

The pull-down Heller-Dor achieved objective results similar to those of esophagectomy with a better quality of life. This technique may be the first choice for end-stage achalasia in patients with null or low risk for cancer or after recurrent dysphagia caused by insufficient myotomy.

Poem Versus Laparoscopic Heller Myotomy in the Treatment of Esophageal Achalasia: A Case-Control Study from Two High Volume Centers Using the Propensity Score

BACKGROUND

POEM has recently had a widespread diffusion, aiming at being the treatment of choice for esophageal achalasia. The results of ongoing RCTs against laparoscopic myotomy are not available, yet. We, therefore, designed this propensity score (PS) case-control study with the aim of evaluating how POEM compares to the long-standing laparoscopic Heller myotomy + Dor fundoplication (LHD) and verifying if it may really replace the latter as the first-line treatment for achalasia.

METHODS

Two groups of consecutive patients undergoing treatment for primary achalasia from January 2014 to November 2017 were recruited in two high-volume centers, one with extensive experience with POEM and one with LHD. Patients with previous endoscopic treatment were included, whereas patients with previous LHD or POEM were excluded. A total of 140 patients in both centers were thus matched. LHD and POEM were performed following established techniques. The patients were followed with clinical (Eckardt score), endoscopic, and pH-manometry evaluations.

RESULTS

The procedure was successfully completed in all the patients. POEM required a shorter operation time and postoperative stay compared to LHD (p < 0.001). No mortality was recorded in either group. Seven complications were recorded in the POEM group (five mucosal perforations) and 3 in the LHD group (3 mucosal perforations)(p = 0.33). Two patients in the POEM group and one in the LHD were lost to follow-up. One patient in both groups died during the follow-up for unrelated causes. At a median follow-up of 24 months [15-30] for POEM and 31 months [15-41] for LHD (p < 0.05), 99.3% of the POEM patients and 97.7% of the LHD patients showed an Eckardt score ≤ 3 (p < 0.12). Four years after the treatment, the probability to have symptoms adequately controlled was > 90% for both groups (p = 0.2, Log-rank test). HR-Manometry showed a similar reduction in the LES pressure and 4sIRP; 24-h pH-monitoring showed however an abnormal exposure to acid in 38.4% of POEM patients, as compared to 17.1% of LHD patients (p < 0.01) and esophagitis was found in 37.4% of the POEM and 15.2% of LHD patients (p < 0.05).

CONCLUSION

POEM provides the same midterm results as LHD. This study confirms, however, a higher incidence of postoperative GERD with the former, even if its real significance needs to be further evaluated.