Diseases of the Esophagus (2017) 30, 1–7
DOI: 10.1093/dote/dox028
Original Article
Peroral endoscopic myotomy versus surgical myotomy for primary achalasia:
single-center, retrospective analysis of 74 patients
S. de Pascale,1 A. Repici,1 F. Puccetti,2 E. Carlani,1 R. Rosati,2 U. Fumagalli3
1
3
2
IRCCS Istituto Clinico Humanitas, Rozzano, Milan, Italy, IRCCS Ospedale San Raffaele, Milan, Italy, and
ASST Spedali Civili di Brescia, piazzale Spedali Civili, Brescia, Italy
SUMMARY. Achalasia is a neurodegenerative motility disorder of the esophagus; dysphagia, weight loss, chest
pain, and regurgitation are its main symptoms. Surgical myotomy (HM) is considered the gold standard treatment.
However, peroral endoscopic myotomy (POEM) seems to be a safe and effective alternative option. The aim of this
study is to compare the safety and efficacy of these techniques. From March 2012 to June 2015, 74 patients with
symptomatic primary achalasia underwent myotomy. The two groups were compared in terms of intraoperative and
postoperative outcomes and Eckardt score at last follow-up. A morphofunctional comparison was also performed.
Thirty-two myotomies were performed endoscopically (POEM group) and 42 were performed laparoscopically with
a 180◦ anterior fundoplication (surgical myotomy [SM] group). Operative time was significantly shorter for the
POEM group (63 [range: 32–114] vs. 76 minutes [54–152]; P = 0.0005). Myotomy was significantly longer for
the POEM group (12 [range: 10–15] vs. 9 cm [range: 7–10]; P = 0.0001). Postoperative morbidity occurred in
two patients (4.7%) in the SM group; no complications (P = not significant) were recorded for the POEM group.
The median Eckardt score at last follow-up decreased for each group from 6 to 1 (P < 0.001). Morphological
evaluation was performed for 20 patients and functional evaluation was performed in 18 patients of each group.
Lower esophageal sphincter resting and relaxation pressures were significantly reduced in both groups (P < 0.001).
Eight patients in the POEM group (40%) had esophagitis at endoscopy: 4 (20%) with Los Angeles (LA) grade
A, 3 (15%) with LA grade B, and 1 patient with LA grade D (5%). Five patients in POEM group (28%) had a
pathologic DeMeester score. In the SM group, one patient (5%) had esophagitis (P = 0.04; 95% CI) and 4 patients
(22%) presented a pathological DeMeester score. Perioperative results for POEM and SM are similar. The absence
of an antireflux wrap leads to an increased risk of reflux with consequent esophagitis. SM with an antireflux wrap
could be a preferred choice when a long standing gastroesophageal reflux could potentially lead to a damage as, for
example, in young patients.
KEY WORDS: antireflux surgery, esophageal achalasia, esophagogastric junction, foregut surgery, laparoscopic
surgery, surgical endoscopy.
INTRODUCTION
Achalasia is a neurodegenerative motility disorder
of the esophagus resulting in impaired esophageal
Address correspondence to: Stefano de Pascale, MD, Istituto
Clinico Humanitas, Via Alessandro Manzoni 56, 20089 Rozzano,
Milano, Italy. Email: [email protected]
Specific author contributions: Stefano de Pascale: Substantial
contributions to the conception of the work; acquisition, analysis
and interpretation of data of the work; agreement to be
accountable for all aspects of the work in ensuring that questions
related to the accuracy or integrity of any part of the work are
appropriately investigated and solved. Alessandro Repici: Revising
the work critically for important intellectual content. Francesco
Puccetti: Drafting the work. Elisa Carlani: Drafting the work.
Riccardo Rosati: Final approval of the version to be published.
Uberto Fumagalli: Substantial contributions to the conception of
the work and final approval of the version to be published.
peristalsis and alteration of lower esophageal
sphincter (LES) function. It is caused by the loss of
inhibitor neurons involved in phasic relaxation of
the LES, main symptoms are dysphagia, weight loss,
regurgitation, and chest pain.
Endoscopic dilation of the cardia or surgical
myotomy (SM) of the LES is used to lower the functional resistance of the LES to bolus progression. Both
are effective treatments for dysphagia, with a 5-year
success rate of more than 90% and a low morbidity
rate, especially for type II achalasia according to the
Chicago classification.1
Traditionally, myotomy has been performed laparoscopically,2 recently, peroral endoscopic myotomy
(POEM) has been used for the endoscopic treatment
of achalasia.
C The Authors 2017. Published by Oxford University Press on behalf of International Society for Diseases of the Esophagus.
All rights reserved. For permissions, please e-mail: [email protected]
1
2 Diseases of the Esophagus
POEM was first performed in 17 patients by Inoue
in 2008;3 to date, in some centers, it has become a
routine technique.4 POEM incorporates the concepts
of natural orifice transluminal endoscopic surgery; it
develops the techniques used in endoscopic submucosal dissection to achieve a division of the esophageal
circular muscle fibers across the esophagogastric junction and into the stomach.5 The technique integrates
the theoretical advantages of endoscopic dilation (no
skin incisions, decreased pain, and less blood loss)
and SM (durable surgical myotomy and single procedure). The aim of this work is to compare retrospectively the clinical results of two groups of patients
with a diagnosis of primary achalasia, with indication for myotomy, treated at our institution between
March 2012 and June 2015 either by surgery or
endoscopy.
MATERIALS AND METHODS
From March 2012 to June 2015, 93 myotomies for
primary achalasia, diffuse esophageal spasm (DES),
or recurrent dysphagia after previous myotomy were
performed in our center. Forty-two patients underwent endoscopic myotomy and 51 underwent surgical myotomy. Patients undergoing surgery for repeat
myotomy (5 POEM and 9 SM) or for DES (5 POEM)
were excluded from this analysis. The data of the
remaining 74 patients who underwent myotomy for
primary achalasia (32 POEM and 42 SM) were used
for this retrospective study, which evaluated singlecenter perioperative results of endoscopic and surgical
myotomy for achalasia in terms of clinical and physiopathologic outcomes at last follow-up.
Inclusion criteria were symptomatic achalasia
with an Eckardt score >3 and preoperative barium
swallow, HR manometry, and esophagogastroduodenoscopy confirming the diagnosis. Manometric
classification were done according to the Chicago
criteria.6 Exclusion criteria were esophageal varices,
coagulopathy, active esophagitis, and gastroesophageal malignancy. Previous endoscopic dilation
or medical treatment was not considered exclusion
criteria.
POEM was mainly performed in patients referred
to the Gastroenterology Division from other centers with the intent to perform the endoscopic procedure. All patients were discussed in a multidisciplinary
meeting with radiologists, surgeons, and gastroenterologists. If both treatments were possibly indicated
patients were selected for the technique for which they
had been referred to our center.
All the endoscopic procedures (POEM) were performed by the same endoscopist (AR). Surgical
myotomies were performed by two different surgeons
(RR, UFR).
Technique
POEM patients received general anesthesia and
all patients received intravenous antibiotics before
the procedure. POEM was performed with highdefinition gastroscopes fitted with a transparent distal
cap and connected to CO2 insufflators. A Hybrid
Knife (Erbe Hybrid Knife; Erbe Elektromedizin,
Tübingen, Germany) was used for submucosal elevation and subsequent mucosal cutting, submucosal
tunneling, and myotomy. After creation of a submucosal bleb of 1.5 to 2 cm in the posterior wall
of the middle esophagus, a mucosal cut was made
to access the submucosa and to start tunneling the
submucosa extending beyond the LES and 2–3 cm
down into the gastric wall. Myotomy of the inner circular muscle bundles was performed, starting approximately 2 cm below the mucosal entry. Myotomy
became full-thickness at the level of the LES and on
the gastric side of tunneling. In the case of large vessels, a Coagrasper (Olympus, Hamburg, Germany) in
the soft coagulation mode was used to ensure firm
coagulation and to prevent intraoperative bleeding.
The mucosal entry was closed with endoscopic clips
(Olympus). Esophagogram was routinely performed
the day after the procedure; in the absence of contrast
leakage, patients resumed a soft diet.
SM has been extensively described elsewhere.7
Briefly, a five-trocar laparoscopic technique was used.
Exposure of the anterior esophageal surface was the
first step. Myotomy was performed in the abdominal and distal thoracic esophagus and extended for
1.5–2 cm on the gastric side of the stomach under
endoscopic control. Mucosal tear, if present, was
repaired with 4/0 monofilament suture. After adequate myotomy was achieved, a Dor fundoplication was performed. A gastrographin swallow was
performed on the first postoperative day; thereafter,
patients were allowed a soft diet. In case of intraoperative mucosal tear, radiologic control was performed on
the third postoperative day. Patients were discharged
if the soft diet was well tolerated.
After POEM, amoxicillin and clavulanic acid was
indicated for 5 days.
Patients in both groups were treated with oral
Proton Pump inhibitors (PPIs) for the following 4
weeks; further therapy with PPIs was on demand.
Patients were also advised to progress from the soft
diet to a regular diet 2 weeks after the procedure.
Patients were initially followed-up at one month
after myotomy; clinical evaluation was performed
using the Eckardt score. A score ≤ 3 was considered a clinical response. Clinical and morphofunctional evaluations including upper gastrointestinal
endoscopy, timed barium swallow, HR manometry,
and 24-hour multichannel intraluminal impedance
(MII) pH-metry were scheduled within the first year of
follow-up. Esophagitis was classified endoscopically
Minimally invasive treatment of achalasia 3
according to the Los Angeles system.8 Every year, a
detailed interview is included with the Eckardt score
determination.
Statistical analysis
Data analysis was performed using the IBM SPSS
Statistics 20. Data are reported as median and range.
Nonparametric tests were used when appropriate,
P < 0.05 was considered statistically significant.
RESULTS
The two groups were comparable for age, sex, previous
treatment for achalasia, symptoms, and symptoms
duration. Seventy-two patients underwent surgery for
type II achalasia. One patient in each group had type
III achalasia.
The median preoperative Eckardt score was 6 for
both groups (POEM group range: 5–12; SM group
range: 4–12). Median duration of symptoms before
surgery was 3 years for both groups (POEM group
range: 0.5–26; SM group range: 0.5–11; P = not significant [n.s.]) (Table 1).
[range: 54–152]; P = 0.0005). Myotomy was significantly longer for the POEM group (12 cm [range: 10–
15] vs. 9 cm [range: 7–10]; P = 0.0001).
One case of intraoperative pneumothorax (PNT)
(3.1%), requiring chest tube placement, occurred in
the POEM group. Minor intraoperative complications were observed in three patients who underwent
POEM (9.3%); they developed pneumoperitoneum
(PNP) requiring decompression at the end of intervention. In the SM group, there were no major intraoperative complications, but five patients (11.9%) had a
mucosal lesion that required suture repair (Table 2).
There were no postoperative complications in the
POEM group. There were two (4.7%) postoperative complications in the SM group (P = n.s.). One
patient had port site bleeding that required repeat
laparoscopy (Clavien Dindo 3b). Another patient had
acute respiratory distress syndrome following postintubation unilateral laryngeal palsy (Clavien Dindo
4a).9
Median postoperative length of stay was 3 days for
the POEM group (range: 2–9) and 2 days for the SM
group (range: 2–7; P = 0.0014).
Clinical results at follow-up
Perioperative results
Duration of surgery was significantly shorter for the
POEM group (63.4 minutes [range: 32–114] vs. 76.5
After a median follow-up of 23.7 months for POEM
(range: 12–46.2) and 26.5 months (range: 12–49) for
SM, the median Eckardt score decreased to 1 in both
groups.
Table 1 Patients characteristics
Age, median (years) [range]
Sex (M/F)
Duration of symptoms, median (years) [range]
Chicago classification
Type I (%)
Type II (%)
Type III (%)
Previous treatment
Endoscopic dilation, n◦ pts (%)
Botox injection, n◦ pts (%)
Eckardt score preoperative, median [range]
POEM (32)
SM (42)
56 [18–83]
20/12
3 [0.5–26]
48 [22–81]
19/23
3 [0.5–11]
0
31 (96.9)
1 (3.1)
0
41 (97.6)
1 (2.4)
3 (9.3)
2 (6.2)
5 (11.9)
3 (7.1)
6 [5–12]
6 [4–12]
Table 2 Procedure related parameters
POEM (32)
63.4 [32–114]
SM (42)
76.5 [54–192]
p
0.0005
Myotomy length,
Total, median cm [range]
Esophageal side, median cm [range]
Gastric side, median cm [range]
12 [10–13]
9 [6–11]
3 [2–4]
9 [7–10]
7 [5–8]
2 [2–2]
0.001
0.001
0.001
Intraoperative major complications
Pneumothorax
1 (3.1)
0
n.s.
Intraoperative minor complications
Pneumoperitonuem decompression (%)
Mucosal tear (%)
3 (9.3)
0
0
5 (11.9)
Operation time, median minutes [range]
4 Diseases of the Esophagus
Table 3
Follow-up: clinical and morphofunctional parameters
Eckardt score [range]
GER symptoms, n◦ pts (%)
High-resolution manometry, n◦ pts (%)
LES basal pressure, median mmHg [range]
Integrated relaxation pressure (IRP), median mmHg [range]
24h MII pH-impedance, n◦ pts (%)
Pathological DeMeester score, n◦ pts (%)
Endoscopy, n◦ pts (%)
Esophagitis, n◦ pts (%)
∗ p-value
POEM (32)
SM (42)
p
1 [0–10]
4 (12.5)
1 [0–3]
4 (9.5)
0.001∗
n.s.
18 (56)
17.5 [3.9–26.2]
9.7 [15.7–60.5]
18 (43)
13.1 [3.5–25.4]
8 [3.5–14]
0.001∗
0.001∗
18 (56)
5 (28)
18 (43)
4 (22)
n.s.
20 (62.5)
8 (40)
20 (47.6)
1 (5)
0.04
obtained from the comparison of preoperative and postoperative results.
One patient in POEM group underwent surgical
myotomy due to symptoms persistence (Eckardt score
of 10) 10 months after endoscopic myotomy. The
failure rate for POEM was 1/32 (3.1%).
Four patients in each group presented heartburn at
their last clinical evaluation (12.5 and 9.5% in POEM
and SM group respectively; P = n.s.); these four
patients were under PPI treatment. Eighteen patients
in each group (56% and 43%) completed the postoperative functional evaluation with HR manometry
and 24-hour MII pH-metry (off-therapy), whereas 20
patients in each group (62.5% and 47.6%) completed
the morphological evaluation with endoscopy. HR
manometry showed a significant decrease in median
LES basal pressure (17.5 [range: 3.9–26.2 mmHg]
and 13.1 mmHg [range: 3.5–25.4]) in the POEM and
SM groups, respectively (P < 0.001 compared to preoperative findings). Median postoperative integrated
relaxation pressure results were 9.7 mmHg (range:
15.7–60.5 mmHg) for the POEM group and 8 mmHg
(range: 3.5–14 mmHg) for the SM group.
At endoscopy, eight patients in the POEM group
(40%) had esophagitis: four (20.0%) LA grade A,
3 (15.0%) LA grade B, and 1 (5%) LA grade D.
One patient in the SM group (5%) had LA grade A
esophagitis (P = 0.04; 95% CI). The 24-hour MII pHmetry showed a pathological DeMeester score in nine
patients (five patients in the POEM group (28%) and
four (22%) in SM group) (Table 3 and Fig. 1).
DISCUSSION
Laparoscopic myotomy is the gold standard for the
surgical treatment of achalasia because of its effective and durable results. Dysphagia is controlled in
more than 85% of patients at 5 years after surgery
with a success rate of 76.1% at a 10-year follow-up.10,11
Postoperative morbidity rate is low and postoperative
hospital stay is short. The occurrence of pathologic
gastroesophageal reflux (GER) is limited by the
application of some technical surgical details: minimal hiatal dissection and adjunct of an antireflux
procedure to myotomy. The occurrence of GER is limited to less than 10%.12
An alternative approach for esophageal myotomy
is POEM, which was introduced clinically in the past
few years. Some studies have demonstrated the feasibility and safety of this procedure showing similar
good results in terms of perioperative results. A metaanalysis of 486 patients showed no differences when
endoscopic and surgical myotomies were compared
in terms of clinical response, operative time, analgesic requirements, postoperative pain, and complications.13 However, length of hospital stay was significantly longer for patients who underwent endoscopic
myotomy, and there was a higher incidence of GER
when compared to SM associated with an antireflux
wrap.13 A recent systematic review and pooled analysis on the results of POEM for the treatment of achalasia showed that this operation is a safe and effective treatment allowing a significant symptomatic and
objective improvement in these patients.14 However
comparative studies between endoscopic and surgical
myotomy are few, mostly reporting a short follow-up.
Zhang et al. have recently published a meta-analysis
on the studies comparing the two techniques: in this
comparison post-operative functional results are not
reported.15
Debate still exists regarding the respective indications of these procedures. Beyond that there are only
few studies reporting the results of POEM and surgical myotomy in terms of esophageal acid exposure
(Table 4).16–22
Our experience confirms that POEM is a safe and
effective procedure for treatment of patients with
achalasia, with low complication index and great efficacy in symptom control. Perioperative data are similar in terms of complication rate and length of postoperative stay confirming what has been reported by
others.
The pattern of intraoperative complications is different. Mucosal tear is a common intraoperative complication of laparoscopic myotomy occurring mainly
Minimally invasive treatment of achalasia 5
Fig. 1 (A) HR manometry pre POEM. (B) HR manometry post POEM. (C) HR manometry pre SM. (D) HR manometry post SM.
Table 4
Review of comparative studies
Ujiki et al.16
Hungness et al.17
Teitelbaum et al. 18
Bhayani et al. 19
Kumagai et al. 20
Schneider et al. 21
Chan et al. 22
Present study
Retrospective
Prospective
Prospective
Retrospective
Prospective
Retrospective
Retrospective
Retrospective
Sample
size
POEM/SM
Eckardt score
reduction∗
pH
test†
Morphological
evaluation‡
HR
Manometry∗∗
39
73
29
101
83
50
56
74
18/21
18/55
12/17
37/64
42/41
25/25
23/33
32/42
P < 0.001
P < 0.001
P < 0.001
P < 0.001
Data n.a
P < 0.001
Data n.a
P < 0.001
Data n.a.§
Data n.a.
Data n.a.
23(39%)/31(32%)
Data n.a.
8 (50%)/7 (30%)
Data n.a.
18 (28%)/18 (22%)
Data n.a
15 (33%)/Data n.a
Data n.a
Data n.a
Data n.a
13 (53%)/19 (32%)
Data n.a
20 (40%)/20 (5%)
Data n.a.
P < 0.001
Data n.a
P < 0.001
Data n.a
P < 0.001
Data n.a
P < 0.001
∗ Significant
symptomatic regression: P value of POEM and SM. ∗∗ Significant improvements in postmyotomy lower esophageal sphincter
profiles: P value of POEM and SM. † Patients receiving postoperative pH tests (% of phatological responses) after POEM /SM. ‡ Patients
receiving postoperative endoscopic follow-up (% of phatological responses) after POEM/SM. § Data not available in the results of the studies.
in patients who underwent previous endoscopic treatment.23 In our experience, the incidence of intraoperative mucosal tear after SM was 11.9% with no relevant
clinical impact on postoperative course since the tear
is almost always recognized and treated immediately
during the procedure.24
Previous endoscopic treatment did not add technical difficulties to the endoscopic procedure. The
most frequent postoperative complication for POEM
patients was PNP; three patients required postoperative PNP decompression and one patient presenting
PNT required a pleural drain.
A similar occurrence of PNP after POEM was
reported with a rate of 39%.17 In this experience,
a macroscopic esophageal mucosal tear occurred
in just one patient, confirming that PNP and
PNT are not necessarily related to macroscopic
mucosal tears. In this setting, PNP requires only
radiological follow-up or a short delay in postoperative refeeding with no other clinical relevance.17 Still, POEM has an advantage over laparoscopic myotomy: it is shorter and allows longer
myotomy.
Endoscopic procedure duration may also depend
on the technique used. Others have demonstrated that
Hybrid Knife for myotomy allows for a significantly
shorter procedure compared with using a conventional triangular tip knife.25
6 Diseases of the Esophagus
Because POEM enables a longer myotomy, it could
be electively indicated for type III achalasia (Chicago
classification); in this case, a longer myotomy could be
the key for better clinical results. Studies showed that
POEM could be used in selected cases to treat type
III achalasia and DES because the length of myotomy
may be tailored after preoperative HR manometric
tomography.26,27
No data are available to date to support this hypothesis. The only available evidence is still that surgical
myotomy and antireflux wrap give the best results for
type III achalasia. The similar efficacy of the two procedures regarding lowering the outflow resistance of
the LES is demonstrated by the significant postoperative decrease in Eckardt score and of LES pressure
at HR manometry. The results of both procedures are
similar in this respect. In our experience, the failure
rate of POEM was of 1/32 patients (3.1%); however,
all patients had short-term symptom control after
SM.
A debate exists on the incidence of esophageal
acid exposure after these procedures. Simple laparoscopic myotomy in patients with achalasia induces
good remission of dysphagia but is characterized by
a high incidence of pathologic GER.28 To reduce
this incidence, a partial antireflux procedure is usually performed. With POEM, no antireflux system
is added; however, it must be considered that endoscopic myotomy does not alter the ligaments around
the esophagus and therefore should be considered less
prone to postoperative pathologic reflux in comparison to laparoscopic myotomy. Some authors stress
the importance of cutting only the circular inner muscular layer of the esophagus during POEM, limiting
the incidence of reflux. Of 131 patients who underwent
a selective section of circular muscle and 103 patients
treated with a full-thickness section of the muscular
layer, no differences were observed in terms of operative time, clinical response, and median LES resting
pressure.29
More than 50% of patients included in this study
had a morphofunctional evaluation at follow-up, a
significant number if compared to what reported in
other studies. Our results on postoperative morphofunctional evaluations show that 40% of patients in
the POEM group had endoscopic esophagitis during
follow-up compared to 5% of SM group. Similarly,
the incidence of pathologic esophageal acid exposure
was higher in patients who underwent the endoscopic
procedure compared with patients who underwent
laparoscopic myotomy. Five patients in the POEM
group and four patients in the SM group had a pathologic DeMeester score (28% vs. 22%; P = n.s.). A similar incidence of endoscopic esophagitis after POEM
has been reported.30,17 The incidence of esophagitis
after endoscopic myotomy seems to remain high at
longer follow-up; a 56.3% incidence of esophagitis at
3 years after POEM has been reported.31
The incidence of objective evidence of excess
esophageal acid exposure after POEM using standard pH monitoring has been reported in 53 out of
124 patients from a recent pooled analysis of five
studies.14
Schneider et al., in a matched comparison of
the two techniques found an abnormal DeMeester
score in both groups of patients (respectively 50%
for POEM and 30% after SM) with a higher incidence of endoscopic esophagitis in patients submitted to POEM.21 Our results are similar to this
experience, demonstrating excellent early clinical outcomes for POEM concerning resolution of dysphagia,
with higher incidence of esophagitis in this group of
patients.
Limitations of this study are its retrospective nature,
the absence of predefined criteria for choosing a procedure and that a morphofunctional follow-up was
not performed in all the patients and its timing was
not always the same. These initial retrospective results
need to be evaluated by the ongoing multicenter
randomized trials comparing these techniques. The
two different esophageal myotomy methods, laparoscopic and endoscopic, appear to be effective in
improving symptoms and outflow obstruction. However, the results of endoscopic myotomy should be
deeply evaluated in terms of quality of life and incidence of pathologic esophageal acid exposure. In
our opinion, this is very important because many
patients who undergo myotomy are young with a
long life expectancy; we should avoid exposing the
esophagus of these patients to long lasting pathologic acid. On the contrary, the endoscopic procedure should be an optimal treatment for recurrent dysphagia after surgery in case of incomplete myotomy:
in these patients an antireflux procedure could balance the increased incidence of reflux recorded after
the simple primary endoscopic myotomy.
In conclusion, in skilled hands, endoscopic
myotomy is a safe and effective technique and perioperative results comparable to surgical myotomy.
The reported incidence of postoperative GER after
endoscopic myotomy is definitely higher than that
reported after myotomy with a partial wrap. Prospective randomized trials should be examined before
POEM is considered the standard for achalasia
patients.
Disclosure
No disclosure.
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