Abstract
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To assess how the addition of a fundoplication affects postoperative reflux and dysphagia in people undergoing LHC and compare the different types of fundoplications used in combination with LHC to determine which is better at controlling reflux without worsening the dysphagia.
Background
Description of the condition
Achalasia is a rare primary motility disorder of the oesophagus characterised by an absence of oesophageal peristalsis and incomplete relaxation of a frequently hypertensive lower oesophageal sphincter (LOS) (Cotran 1999). The incidence of achalasia is about 1 in 100,000 people per year and the prevalence is about 10 per 100,000 people (Sadowski 2010). The likely cause of achalasia is myenteric inflammation with injury to and subsequent loss of ganglion cells and fibres of myenteric nerves (Goldblum 1996).
Affected people usually present with one or more of the following symptoms: dysphagia to both solid and liquid diet (greater than 90%), regurgitation of undigested food (76% to 91%), nocturnal cough (30%), aspiration (8%), chest pain (25% to 64%), heartburn (18% to 52%) and weight loss (35% to 91%) (Boeckxstaens 2014). The investigations performed to confirm diagnosis are:
barium swallow which shows a smooth tapering of the lower oesophagus (bird's beak appearance);
oesophageal manometry which shows reduced peristalsis of the oesophagus with hypertensive, non‐relaxing LOS;
oesophagogastrodudenoscopy to rule out any tumour at the gastro‐oesophageal junction (pseudo‐achalasia) (Pandolfino 2015; Stefanidis 2012; Vaezi 2013).
The treatments available are:
pharmacotherapy: calcium channel blockers and long‐acting nitrates;
botulinum toxin injections into the LOS;
pneumatic dilation of the LOS;
peroral endoscopic myotomy (POEM);
laparoscopic Heller's cardiomyotomy (LHC);
robotic Heller's cardiomyotomy.
Pharmacotherapeutic agents have to be taken every day, have incomplete symptom control and lose their potency over time. Botulinum toxin injection relieves symptoms in 85% of people but its effects only last for 6 to 12 months (Pandolfino 2015; Stefanidis 2012; Vaezi 2013). Pneumatic dilation is currently considered the most effective non‐surgical treatment with a response rate ranging from 50% to 93% at 10 years with on‐demand repeat dilations (Pandolfino 2015; Stefanidis 2012; Vaezi 2013). Treatment with single dilation is only effective in 13% of people (Stefanidis 2012). LHC provides symptomatic improvement in 89% (range 77% to 100%) of people on long‐term follow‐up (Campos 2009), and is superior to open abdominal, thoracic or thoracoscopic approaches of Heller's cardiomyotomy (Campos 2009; Stefanidis 2012). POEM was first described in 2010 (Inoue 2010) and short‐term results show that it might be more effective than LHC in relieving dysphagia but it is associated with very high incidence (29%) of pathological reflux (Familari 2016; Schlottmann 2018). The long‐term results of this procedure are still not available. Robotic Heller's cardiomyotomy was first reported 2001 (Melvin 2001) and compared to LHC has reduced incidence of intraoperative oesophageal mucosal perforations but there is no clear advantage in postoperative morbidity, symptom relief and long‐term outcomes (Maeso 2010). LHC with a fundoplication is considered the surgical treatment of choice for achalasia (Campos 2009; Stefanidis 2012).
See Appendix 1 for glossary of terms.
Description of the intervention
LHC is performed under general anaesthesia (Sharp 2002). Five ports are placed on the upper anterior abdomen to introduce a laparoscopic camera, a liver retractor and the instruments (Pellegrini 1992; Sharp 2002). The anterior phreno‐oesophageal ligament is divided at the hiatus to expose the anterior surface of the oesophagus. This limited hiatal dissection is preferred over circumferential hiatal dissection with disruption of posterior oesophageal attachments, as it produces less acid reflux postoperatively (Bonavina 2006; Braghetto 2007). The muscles of the oesophagus, including the LOS, are divided at the gastro‐oesophageal junction to expose the mucosa. The division of the muscles is carried proximally into the oesophagus for 4 cm to 6 cm and distally into the stomach for 1 cm to 2 cm (Sharp 2002; Stefanidis 2012). Any hiatal defect is then apposed using interrupted non‐absorbable sutures (Stefanidis 2012). Some surgeons perform simultaneous intraoperative endoscopy to assess the adequacy of the myotomy and rule out any oesophageal mucosal perforation (Sharp 2002).
A fundoplication is added to LHC to reduce the symptoms of gastro‐oesophageal reflux, produced by division of the LOS (Campos 2009; Stefanidis 2012). In fundoplication, the greater curvature of the stomach may be mobilised by dividing the short gastric vessels and wrapped around the lower oesophagus to produce an artificial sphincter (Hunter 1997). Depending on the amount of circumference of the oesophagus encircled by the stomach wrap, the fundoplications are classified as total (360° or Nissen) or partial. The most common partial fundoplications used with LHC are Dor (anterior 180° wrap) and Toupet (posterior 270° wrap). When a Dor fundoplication is created, the fundus is sutured to each edge of the myotomy and to the right crus with non‐absorbable sutures and overlies the anterior surface of the distal oesophagus including the myotomy defect (Dempsey 2004). If a Toupet fundoplication is created, the mobilised fundus is pulled from left to right behind the oesophagus and is sutured to the edges of the myotomy wound on each side. It creates a wrap covering the posterior and lateral aspects of the oesophagus leaving the mucosa in the floor of the myotomy wound exposed (Katada 2006). In Nissen fundoplication, the fundus is pulled from left to right behind the oesophagus and is sutured on to itself in front of the oesophagus, forming a complete wrap encircling the distal oesophagus (Rossetti 2005).
How the intervention might work
The division of the muscles (myotomy) of the hypertensive, non‐relaxing LOS relieves the symptoms of dysphagia but it can also cause significant gastro‐oesophageal reflux (Burpee 2005; Kjellin 1999). A fundoplication is added to LHC (Campos 2009; Stefanidis 2012), to create an artificial sphincter and prevent gastro‐oesophageal reflux and it symptoms.
Why it is important to do this review
The role of fundoplication in combination with LHC is debatable. Many studies have reported that addition of a fundoplication does not improve the reflux symptoms following LHC (Gupta 2005; Lyass 2003; Sharp 2002). However, Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) guidelines for the surgical treatment of achalasia strongly recommend that a person undergoing myotomy should have a fundoplication to prevent reflux (Stefanidis 2012). One systematic review and meta‐analysis of endoscopic and surgical treatment of achalasia concluded that laparoscopic myotomy with fundoplication was the most effective surgical treatment (Campos 2009).
There is no agreement on which type of fundoplication is better at controlling the reflux symptoms without worsening the dysphagia. An anterior 180° Dor fundoplication (Cuttitta 2011; Rice 2005), a posterior 270° Toupet fundoplication (Katada 2006; Kurian 2013), and complete 360° Nissen fundoplication (Di Martino 2011; Rossetti 2005) have all been proposed to be effective in combination with Heller's cardiomyotomy. SAGES guidelines for the surgical treatment of achalasia have recommended a partial fundoplication over total fundoplication because of decreased dysphagia rates and similar reflux control but has not recommended which partial fundoplication provides best reflux control following LHC (Stefanidis 2012).
There are a few systematic reviews on this topic, but their conclusions are not clear and their evidence is limited due to lack of randomised controlled trials (RCT) (Kurian 2013; Mayo 2012; Wei 2013). Since 2013, some new RCTs have been published comparing different types (Gupta 2018; Torres‐Villalobos 2018) of fundoplications in association with LHC and hence there is an opportunity to revisit the topic and perform a systematic review on the role of fundoplication in people undergoing LHC and which fundoplication is best suited for this purpose.
Objectives
To assess how the addition of a fundoplication affects postoperative reflux and dysphagia in people undergoing LHC and compare the different types of fundoplications used in combination with LHC to determine which is better at controlling reflux without worsening the dysphagia.
Methods
Criteria for considering studies for this review
Types of studies
We will include only RCTs. We will include studies which have been reported as full text, those published as abstracts only and any unpublished data. We will include studies which have been published in any language.
Types of participants
We will only include studies recruiting adults (aged 18 years or older) undergoing LHC for achalasia. We will exclude studies where the participants are younger than 18 years.
Types of interventions
We will only include studies where Heller's cardiomyotomy and fundoplication have been performed laparoscopically using limited hiatal dissection. We will include studies where one type of fundoplication is compared with a different type of fundoplication in people undergoing LHC for achalasia. We will also include studies where a type of fundoplication combined with LHC is compared against LHC without any fundoplication.
We will exclude studies where interventions have been performed with open surgery or where LHC has been performed with circumferential hiatal dissection. We will also exclude studies where LHC with or without fundoplication has been compared with non‐surgical interventions (e.g. endoscopic dilation, botulinum toxin injections or POEM).
Types of outcome measures
Primary outcomes
Postoperative pathological acid reflux: obtained from pH studies (between six months and one year following surgery).
Postoperative dysphagia requiring medical or surgical intervention (between six months and one year following surgery).
Secondary outcomes
Health‐related quality of life scores (between six months to one year following surgery).
Major complications (Clavien‐Dindo Grade III and above) (Clavien 2009; Dindo 2004): for example, perforation, pneumothorax and bleeding (within three months of surgery).
LOS pressures: obtained from postoperative oesophageal manometry (after six months).
DeMeester score: obtained from postoperative pH studies (after six months).
Length of hospital stay.
Operating time.
Postoperative gastro‐oesophageal reflux and recurrent dysphagia are the two major complications in people undergoing LHC for achalasia. Pathological acid reflux obtained from pH studies is used to objectively diagnose reflux and to correlate it with the person's symptoms. DeMeester score obtained from pH studies is a composite outcome and values above 14 usually indicate significant reflux. Recurrent dysphagia after LHC can be of varying severity, from mild intermittent symptoms which do not need treatment, to persistent severe dysphagia requiring medical or surgical treatment. In our study, we will only include severe dysphagia requiring medical or surgical intervention as a primary outcome as milder dysphagia is difficult to measure and could be due to aperistalsis of the oesophagus which is associated with achalasia. The LOS sphincter pressure obtained by postoperative oesophageal manometry is another indirect test to determine the constricting force of the fundoplication around the distal oesophagus which could lead to dysphagia.
We will also use other standard outcomes for comparing interventions such as quality of life scores, major complications, length of hospital stay and operating time, to compare the different types fundoplications.
Reporting of the outcomes listed here will not be an inclusion criteria for the review.
Search methods for identification of studies
We will use the search strategies developed with the help of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Information Specialist before performing literature searches. There will be no restrictions on the language of publication when searching the electronic databases, or reviewing reference lists in identified studies.
Electronic searches
We will conduct a literature search to identify all published and unpublished RCTs in all languages. We will translate non‐English language papers and fully assess them for potential inclusion in the review as necessary. We will search the following electronic databases:
Cochrane Central Register of Controlled Trials (CENTRAL; Appendix 2);
MEDLINE (OvidSP; 1966 to present; Appendix 3);
Embase (OvidSP; 1988 to present; Appendix 4);
Searching other resources
We will check the reference list of all primary studies and review articles for additional references. We will contact authors of the identified trials and ask them to identify other published and unpublished studies.
We will search for errata or retractions from eligible trials on PubMed (www.ncbi.nlm.nih.gov/pubmed), and report the date this was done in the review.
Data collection and analysis
Selection of studies
Two review authors (SM and DG) will independently screen titles and abstracts for inclusion. We will code all of the potential studies we identify as a result of the search as 'retrieve' (eligible, potentially eligible or unclear) or 'do not retrieve'. We will retrieve the full text of potentially eligible studies and two review authors (SM and DG) will independently screen the full text, and identify studies for inclusion, and identify and record reasons for exclusion of the ineligible studies. We will resolve any disagreements through discussion or, if required, we will consult a third review author (MWM). We will identify and exclude duplicates and collate multiple reports of the same study, so that each study rather than each report is the unit of interest in the review. We will record the selection process in sufficient detail to complete a PRISMA flow diagram and 'Characteristics of excluded studies' table.
Data extraction and management
We will use a standardised data collection form for study characteristics and outcome data, which we will pilot on at least one study included in the review. Two review authors (SM and DG) will independently extract the following study characteristics from the included studies:
methods: study design, total duration study and run in, number of study centres and location, study setting, withdrawal, date of study;
participants: number, mean age, age range, gender, type of achalasia, American Anaesthesiologist Association (ASA) status (ASA 2014), inclusion criteria, exclusion criteria;
interventions: intervention, comparison, concomitant intervention;
outcomes: primary and secondary outcomes specified and collected, time points reported;
notes: funding for trial, notable conflicts of interest of trial authors.
Two review authors (SM and MWM) will independently extract outcome data from the included studies. We will note in the 'Characteristics of included studies' table if the study authors reported outcome data in a usable way. We will resolve disagreements by consensus or by involving a third review author (MWM). One review author (SM) will copy across the data from the data collection form into Review Manager 5 (Review Manager 2014). A second review author will spot‐check study characteristics for accuracy against trial reports.
Assessment of risk of bias in included studies
Two review authors (SM and DG) will independently assess the risk of bias for each included study, using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We will resolve any disagreements by discussion, or by involving the third review author (MWM). We will assess the risk of bias according to the following domains:
random sequence generation;
allocation concealment;
blinding of participants and personnel;
blinding of outcome assessment;
incomplete outcome data;
selective outcome reporting;
other bias: funding source, conflict of interest of authors.
We will grade each potential source of bias as high, low or unclear, and provide a quote from the study report and justification for our judgement in the 'Risk of bias' table. We will summarise the 'Risk of bias' judgements across studies for each of the domains listed. We will consider blinding separately for different key outcomes where necessary (e.g. for blinded outcome assessment, risk of bias for all‐cause mortality, may be very different than for a person‐reported pain scale). Where information on risk of bias relates to unpublished data or correspondence with a study author, we will note this in the 'Risk of bias' table.
When considering treatment effects, we will take into account the risk of bias for the studies that contribute to that outcome, as a part of the GRADE methodology (Section 8.5 and Chapter 12 of the Cochrane Handbook of Systematic Reviews of Interventions; Higgins 2011).
Measures of treatment effect
We will analyse dichotomous data (pathological acid reflux, dysphagia and complications) as risk ratio (RR) and continuous data (LOS pressure, quality of life scores, length of hospital stay and operating time) as mean difference (MD) with 95% confidence intervals (CI). If it is not possible to calculate the MD from the available data, we will use standardised mean difference (SMD) instead of MD. We will ensure that higher scores for continuous outcomes have the same meaning for the particular outcome, explain the direction to the reader and report where the directions were reversed if this was necessary.
We will undertake meta‐analyses only where this is meaningful, that is, if the treatments, participants and the underlying clinical question are similar enough for pooling to make sense.
A common way that trialists indicate they have skewed data is by reporting medians and interquartile ranges. when we encounter this, we will note that the data are skewed and consider the implication of this. If the data are skewed, we will not perform a meta‐analysis, but we will provide a narrative summary instead.
Where multiple arms are reported in a single trial, we will include only the relevant arm. We will list the other arms in the 'Characteristics of included studies' table.
Unit of analysis issues
The unit of analysis will be the individual participant undergoing LHC (with or without a fundoplication) for achalasia.
Dealing with missing data
We will contact the investigators or study sponsors in order to verify key study characteristics and obtain missing numerical outcome data as indicated (e.g. when a study is identified as abstract only). If we are unable to obtain the information from the investigators or study sponsors, we will impute the mean from the median (i.e. consider median as mean) and standard deviation from standard error, interquartile range or P values, according to the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011). We will assess the impact of including such studies indicated in a sensitivity analysis. If we are unable to calculate the standard deviation from standard error, interquartile range or P values, we will impute the standard deviation as the highest standard deviation of all the remaining trials included in the outcome, fully aware that this method of imputation will decrease the weight of the studies in the meta‐analysis of MD, and shift the effect towards no effect for SMD.
Assessment of heterogeneity
We will use the I2 statistic to measure heterogeneity among the trials in each analysis (Higgins 2003). If we identify substantial or considerable heterogeneity (greater than 50% ) as per Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011), we will explore it using prespecified subgroup analysis. We will also assess heterogeneity by evaluating whether there is good overlap of CIs.
Assessment of reporting biases
If we are able to pool more than 10 trials, we will create and examine a funnel plot to explore possible publication biases. We will use Egger's test to determine the statistical significance of the reporting bias (Egger 1997). We will consider P less than 0.05 to be a statistically significant reporting bias.
Data synthesis
We will perform the meta‐analysis using Review Manager 5 (Review Manager 2014). We will use the random‐effects model by default. For testing the robustness of our findings regardless of which method was chosen, we will conduct a sensitivity analyses for primary outcomes using a fixed‐effect model. In case of divergence between the two models, we will present both results; otherwise, we will present only results from the random‐effects model. We will group the studies according to the fundoplications they compare (e.g. Nissen versus Dor, Dor versus Toupet, etc.) and perform separate meta‐analysis for each group. We will also group all the RCTs comparing one type of fundoplication against no fundoplication and analyse the results.
'Summary of findings' table
We will create a 'Summary of findings' table for all the outcomes in each group (postoperative pathological acid reflux, postoperative dysphagia requiring medical or surgical intervention, health‐related quality of life scores, major complications, LOS pressures, DeMeester score, length of hospital stay and operating time). We will use the five GRADE consideration (study limitation, consistency of effect, imprecision, indirectness and publication bias) to assess the quality of the body of evidence based on the studies that contributed data to the meta‐analyses for each outcome, classifying it as high, moderate, low or very low quality. We will use the methods and recommendations described in Section 8.5 and Chapter 12 of the Cochrane Handbook of Systematic Reviews of Interventions (Higgins 2011), and GRADEpro GDT software (GRADEpro 2015). We will justify all decisions to downgrade or upgrade the quality of the included studies in the footnotes, and where necessary, provide comments to aid the reader's understanding of the review. We will consider whether there is additional outcome information that was not incorporated into the meta‐analyses, note this in the comments, and state if it supports or contradicts the information from the meta‐analyses.
Subgroup analysis and investigation of heterogeneity
We will carry out subgroup analyses comparing:
different age groups;
men versus women;
different ASA groups;
severity of achalasia.
We will use the following outcomes in subgroup analyses:
postoperative pathological acid reflux;
postoperative dysphagia requiring medical or surgical intervention.
We will use the Chi2 test for subgroup difference to test for subgroup interactions.
Sensitivity analysis
We will perform sensitivity analysis defined to assess the robustness of our conclusions. This will involve:
excluding trials with unclear or high risk of bias;
excluding trials where the mean and standard deviation were imputed.
Reaching conclusions
We will only base our conclusions on findings from the quantitative or narrative synthesis of studies included in this review. We will avoid making recommendations for practice; our implications for research will give the reader a clear sense of the needed focus of future research and remaining uncertainties in the field.
Acknowledgements
We acknowledge the help we received from Mr Kurinchi Selvan Gurusamy, Department of Surgery, UCL Medical School, London, throughout the process of preparing this protocol and, without his help, we could not have written this protocol.
We thank Mr Michael Booth, Consultant Upper Gastrointestinal Surgeon at the Royal Berkshire Hospital, Reading, for his valuable suggestions and constant support.
We thank the library services of Royal Berkshire Hospital, Reading for providing access to journal papers.
We thank Ms Karin Dearness and Ms Yuhong (Cathy) Yuan of Cochrane Upper Gastrointestinal and Pancreatic Diseases (UGPD) Group for providing administrative help and logistical support in writing this protocol. The authors would also like to thank the editors of the Cochrane UGPD Group for giving us the opportunity to present our work. We are extremely grateful to the peer referees Marilyn Walsh, Sarah Rhodes and Marcello Di Martino, who very kindly found time to go through the protocol and provided valuable feedback to improve the protocol.
Appendices
Appendix 1. Glossary of terms
Achalasia: disease where the valve at the lower end of the gullet is in a permanent state of contraction causing difficulty in swallowing.
Anterior: front.
Aspiration: food or fluids entering the airway.
Barium swallow: an investigation to assess swallowing by x‐ray imaging when the patient is swallowing a radio‐opaque dye.
Botox: botulinum toxin which causes long‐term relaxation of smooth muscles.
Cardiomyotomy: division of the muscles forming a valve at the junction of the gullet and stomach.
Crus: elongated attachment of the diaphragm to the spine.
Circumferentital: encircling.
Diaphragm: flat muscle separating the chest and abdominal cavities.
Dissection: surgical act of cutting and separating tissues.
Distally: away from the point of attachment.
Dysphagia: difficulty in swallowing.
Endoscopy: examination of the gullet, stomach and intestine using a flexible camera.
Fundoplication: wrapping the top of the stomach around the lower end of the gullet to form an artificial valve.
Ganglion cells: a collection of nerve cells.
Gastro: related to stomach.
Gastro‐oesophageal junction: where the stomach and oesophagus join.
General anaesthesia: a state of medically induced unconsciousness during surgery.
Heartburn: burning sensation in the chest due to regurgitation of stomach acid in the gullet.
Hiatus: an opening in the diaphragm through which the oesophagus enters the abdominal cavity from the chest.
Hypertensive: higher than normal pressure.
Intraoperative: occurring during surgery.
Laparoscopy: keyhole surgery.
LOS sphincter: muscle valve at the lower end of the gullet.
Manometry: investigation to measure the pressures.
Morbidity: illness or disease.
Myenteric: related to muscle layers in the intestine.
Myotomy: the surgical division of a muscle.
Nocturnal: relating to night time.
Oesophagogastroduodenoscopy: examination of the oesophagus, stomach and duodenum (first part of the intestine) with a flexible camera.
Oesophagus: gullet or the tubular structure that carries food from the mouth to the stomach.
Peristalsis: muscular contraction of the gullet or intestine which help to push the food forward.
Peroral: by mouth.
Pharmacotherapy: treatment with medicines.
Pneumatic dilation: stretching using gas or air under high pressure.
Postoperative: occurring after surgery.
Ports: small surgical openings used in keyhole surgery to insert instruments in the body cavity.
Proximally: close to the point of attachment.
Pseudo‐achalasia: dysphagia similar to achalasia caused by other diseases like tumours of the gullet.
Reflux: regurgitation of food and acid from the stomach into the gullet and mouth.
Regurgitation: bringing up undigested food from the stomach into the mouth.
Retractor: a surgical instrument used to expose the site of operation.
Sphincter: a ring of muscle that acts like a valve.
Thoracic: related to chest cavity.
Appendix 2. CENTRAL search strategy (via OvidSP)
1. exp Esophageal Achalasia/ 2. ((oesophag* or esophag* or cardia*) and achalasia*).tw,kw. 3. (cardiospasm* or (cardia adj3 spasm*) or (cardia adj2 spastic contraction*) or megaesophag* or megaoesophag* or mega oesophag* or mega esophag*).tw,kw. 4.((esophag* or oesophag*) adj5 aperistalsis).tw,kw. 5. or/1‐4 6. exp Laparoscopy/ 7. laparoscop*.tw,kw. 8. myotom*.tw,kw. 9. (esophagomyotom* or oesophagomyotom* or oesophagocardiomyotom* or esophagocardiomyotom*).tw,kw. 10. cardiomyotom*.tw,kw. 11. (Heller* or LHM or LHC).tw,kw. 12. or/6‐11 13. 5 and 12
Appendix 3. MEDLINE search strategy (via OvidSP)
exp Esophageal Achalasia/
((oesophag* or esophag* or cardia*) and achalasia*).tw,kw.
(cardiospasm* or (cardia adj3 spasm*) or (cardia adj2 spastic contraction*) or megaesophag* or megaoesophag* or mega oesophag* or mega esophag*).tw,kw.
((esophag* or oesophag*) adj5 aperistalsis).tw,kw.
or/1‐4
exp Laparoscopy/
laparoscop*.tw,kw.
myotom*.tw,kw.
(esophagomyotom* or oesophagomyotom* or oesophagocardiomyotom* or esophagocardiomyotom*).tw,kw.
cardiomyotom*.tw,kw.
(Heller* or LHM or LHC).tw,kw.
or/6‐11
5 and 12
randomized controlled trial.pt.
controlled clinical trial.pt.
random*.ab.
placebo.ab.
trial.ab.
groups.ab.
or/14‐19
exp animals/ not humans.sh.
20 not 21
13 and 22
Appendix 4. Embase search strategy (via OvidSP)
esophagus achalasia/
((oesophag* or esophag* or cardia*) and achalasia*).tw,kw.
(cardiospasm* or (cardia adj3 spasm*) or (cardia adj2 spastic contraction*) or megaesophag* or megaoesophag* or mega oesophag* or mega esophag*).tw,kw.
((esophag* or oesophag*) adj5 aperistalsis).tw,kw.
or/1‐4
exp Laparoscopy/
laparoscop*.tw,kw.
exp myotomy/ or myotom*.tw,kw.
(esophagomyotom* or oesophagomyotom* or oesophagocardiomyotom* or esophagocardiomyotom*).tw,kw.
cardiomyotom*.tw,kw.
(Heller* or LHM or LHC).tw,kw.
or/6‐11
5 and 12
random:.tw.
clinical trial:.mp.
placebo:.mp.
double‐blind:.tw.
or/14‐17
exp animal/ not human/
18 not 19
13 and 20
Contributions of authors
Conceiving the protocol: SM.
Designing the protocol: SM, MWM.
Co‐ordinating the protocol: SM.
Designing the search strategies: SM.
Writing the protocol: SM.
Providing critical comments on the protocol: DG, MWM.
Performing previous work that was the foundation of the current study: SM, MWM.
Declarations of interest
SM: none.
DG: none
MWM: none.
New
References
Additional references
- American Society of Anaesthesiologists. ASA physical status classification system, 2014. www.asahq.org/resources/clinical‐Information/asa‐physical‐status‐classification‐system (accessed prior to 22 July 2019).
- Boeckxstaens GE, Zaninotto G, Richter JE. Achalasia. Lancet 2014;383:83‐93. [DOI] [PubMed] [Google Scholar]
- Bonavina L. Minimally invasive surgery for esophageal achalasia. World Journal of Gastroenterology 2006;12(37):5921‐5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Braghetto I, Korn O, Valladares H, Rodriguez A, Dabandi A, Brunet L. Laparoscopic anterior cardiomyotomy plus anterior Dor fundoplication without division of lateral and posterior periesophageal anatomic structures for treatment of achalasia of esophagus. Surgical Laparoscopy, Endoscopy & Percutaneous Techniques 2007;17(5):369‐74. [DOI] [PubMed] [Google Scholar]
- Burpee SE, Mamazza J, Schlachta CM, Bendavid Y, Klein L, Moloo H, et al. Objective analysis of gastroesophageal reflux after laparoscopic Heller myotomy: an anti‐reflux procedure is required. Surgical Endoscopy 2005;19(1):9‐14. [DOI] [PubMed] [Google Scholar]
- Campos GM, Vittinghoff E, Rabl C, Takata M, Gadenstatter M, Lin F, et al. Endoscopic and surgical treatments of achalasia: a systematic review and meta‐analysis. Annals of Surgery 2009;249(1):45‐7. [DOI] [PubMed] [Google Scholar]
- Clavien PA, Barkun J, Oliveria ML, Vauthey JN, Dindo D, Schulick RD, et al. The Clavien‐Dindo classification of surgical complications: five years experience. Annals of Surgery 2009;250(2):187‐96. [DOI] [PubMed] [Google Scholar]
- Cotran RS, Kumar V, Collins T. Robbins Pathological Basis of Disease. 6th Edition. Philadelphia (PA): WB Saunders, 1999. [Google Scholar]
- Cuttitta A, Tancredi A, Andriulli A, Santo E, Fontana A, Pellegrini F, et al. Fundoplication after Heller myotomy: a retrospective comparison between Nissen and Dor. Eurasian Journal of Medicine 2011;43:133‐40. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dempsey DT, Delano M, Bradley K, Kolff J, Fisher C, Caroline D, et al. Laparoscopic esophagomyotomy for achalasia. Does anterior hemifundoplication affect clinical outcome?. Annals of Surgery 2004;239(6):779‐87. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Martino N, Brillantino A, Monaco L, Marano L, Schettino M, Porfidia R, et al. Laparoscopic calibrated total vs partial fundoplication following Heller myotomy for oesophageal achalasia. World Journal of Gastroenterology 2011;17(29):3431‐40. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Annals of Surgery 2004;240(2):205‐13. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Egger M, Davey Smith G, Schneider M, Minder C. Bias in meta‐analysis detected by a simple, graphical test. BMJ 1997;315(7109):629‐34. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Familari P, Greco S, Gigante G, Cali A, Boskoski I, Onder G, Perri V, Costamagna G. Gastroesophageal reflux disease after peroral endoscopic myotomy: Analysis of clinical procedural and functional factors, associated with gastroesophageal reflux disease and esophagitis. Digestive Endoscopy 2016;28(1):33‐41. [DOI] [PubMed] [Google Scholar]
- Goldblum JR, Rice TW, Richter JE. Histologic features in esophagomyotomy specimens from patients with achalasia. Gastroenterology 1996;111:648‐54. [DOI] [PubMed] [Google Scholar]
- McMaster University (developed by Evidence Prime). GRADEpro GDT. Hamilton (ON): McMaster University (developed by Evidence Prime), 2015.
- Gupta R, Sample C, Bamehriz F, Birch D, Anvari M. Long‐term outcomes of laparoscopic Heller cardiomyotomy without and anti‐reflux procedure. Surgical Laparoscopy, Endoscopy & Percutaneous Techniques 2005;15(3):129‐32. [DOI] [PubMed] [Google Scholar]
- Gupta P, Parshad R, Balakrishna P, Saraya A, Makharia GK, Sachdeva S, et al. Angle of His accentuation is a viable alternative to Dor fundoplication as an adjunct to laparoscopic Heller cardiomyotomy: Results of a Randomized Clinical Study. Digestive Diseases and Sciences 2018;63(9):2395‐404. [DOI] [PubMed] [Google Scholar]
- Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta‐analysis. BMJ 2003;327(414):557‐60. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Higgins JP, Green S, editor(s). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from handbook.cochrane.org.
- Hunter JG, Trus TL, Branum GD, Waring JP. Laparoscopic Heller myotomy and fundoplication for achalasia. Annals of Surgery 1997;225(6):655‐65. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Inoue H, Minami H, Kobayashi Y, Sato Y, Kaga M, Suzuki M, et al. Peroral endoscopic myotomy (POEM) for esophageal achalasia. Endoscopy 2010;42(4):265‐71. [PUBMED: 20354937] [DOI] [PubMed] [Google Scholar]
- Katada N, Sakuramoto S, Kobayashi N, Futawatari N, Kuroyama S, Kikuchi S, et al. Laparoscopic Heller myotomy with Toupet fundoplication for achalasia straightens the esophagus and relieves dysphagia. American Journal of Surgery 2006;192:1‐8. [DOI] [PubMed] [Google Scholar]
- Kjellin AP, Granqvist S, Ramel S, Thor KB. Laparoscopic myotomy without fundoplication in patients with achalasia. European Journal of Surgery 1999;165(12):1162‐6. [DOI] [PubMed] [Google Scholar]
- Kurian AA, Bhayani N, Sharata A, Reavis K, Dunst CM, Swanstrom LL. Partial anterior vs partial posterior fundoplication following transabdominal esophagocardiomyotomy for achalasia of the esophagus: meta‐regression of objective postoperative gastroesophageal reflux and dysphagia. JAMA 2013;148(1):85‐90. [DOI] [PubMed] [Google Scholar]
- Lyass S, Thoman D, Steiner JP, Phillips E. Current status of an antireflux procedure in laparoscopic Heller myotomy. Surgical Endoscopy 2003;17:554‐8. [DOI] [PubMed] [Google Scholar]
- Maeso S, Reza M, Mayol JA, Blasco JA, Guerra M, Andradas E, et al. Efficacy of the Da Vinci Surgical System in abdominal surgery compared with that of laparoscopy: a systematic review and meta‐analysis. Annals of Surgery 2010;252(2):254‐62. [DOI] [PubMed] [Google Scholar]
- Mayo D, Griffiths EA, Khan OA, Symankiewicz MA, Wakefield CW, Thompson SK. Does the addition of a fundoplication improve outcomes for patients undergoing laparoscopic Heller's cardiomyotomy?. International Journal of Surgery 2012;10:301‐4. [DOI] [PubMed] [Google Scholar]
- Melvin WS, Needleman BJ, Krause KP, Wolf RK, Michler RE, Ellison EC. Computer‐assisted robotic Heller myotomy: initial case report. Journal of Laparoendoscopic & Advanced Surgical Techniques. Part A 2001;11(4):251‐3. [DOI] [PubMed] [Google Scholar]
- Pandolfino JE, Gawron AJ. Achalasia: a systematic review. JAMA 2015;313(18):1841‐52. [DOI] [PubMed] [Google Scholar]
- Pellegrini C, Wetter LA, Patti M, Leichter R, Mussan G, Mori T, et al. Thoracoscopic esophagectomy – initial experience with a new approach for the treatment of achalasia. Annals of Surgery 1992;26(3):291‐6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- The Nordic Cochrane Centre, The Cochrane Collaboration. Review Manager (RevMan). Version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014.
- Rice TW, McKelvey AA, Richter JE, Barker ME, Vaezi MF, Feng J, et al. A physiologic clinical study of achalasia: should Dor fundoplication be added to Heller myotomy?. Journal of Thoracic and Cardiovascular Surgery 2005;130(6):1593‐600. [DOI] [PubMed] [Google Scholar]
- Rossetti G, Brusciano L, Amato G, Maffettone V, Napolitano V, Russo G, et al. A total fundoplication is not an obstacle to esophageal emptying after Heller myotomy for achalasia: results of a long term follow up. Annals of Surgery 2005;241(4):614‐21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sadowski DC, Ackah F, Jiang B, Svenson LW. Achalasia: incidence, prevalence and survival. A population based study. Neurogastroenterology and Motility 2010;22(9):e256‐61. [DOI] [PubMed] [Google Scholar]
- Schlottmann F, Luckett DJ, Fine J, Shaheen NJ, Patti MG. Laparoscopic Heller myotomy versus peroral endoscopic myotomy (POEM) for achalasia: a systematic review and meta‐analysis. Annals of Surgery 2018;267(3):451‐60. [DOI] [PubMed] [Google Scholar]
- Sharp KW, Khaitan L, Scholz S, Holzman D, Richards WO. 100 consecutive minimally invasive Heller myotomies: lessons learned. Annals of Surgery 2002;235(5):631‐9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stefanidis D, Richardson W, Farrell TM, Kohn GP, Augenstein V, Fanelli R. SAGES guidelines for the surgical treatment of esophageal achalasia. Surgical Endoscopy 2012;26:296‐311. [DOI] [PubMed] [Google Scholar]
- Torres‐Villalobos G, Coss‐Adam E, Furuzawa‐Carballeda J, Romero‐Hernandez F, Blancas‐Brena B, Torres‐Landa S, et al. Dor vs Toupet fundoplication after laparoscopic Heller myotomy: Long ‐term Randomized Controlled Trial evaluated by High‐resolution manometry. Journal of Gastrointestinal Surgery 2018;22(1):13‐22. [DOI] [PubMed] [Google Scholar]
- Vaezi MF, Pandolfino JE, Vela MF. ACG clinical guideline: diagnosis and management of achalasia. American Journal of Gastroenterology 2013;108:1238‐49. [DOI] [PubMed] [Google Scholar]
- Wei M, He Y, Deng X, Zhang Y, Yang T, Jin C, et al. Is Dor fundoplication optimum after laparoscopic Heller myotomy for achalasia? A meta‐analysis. World Journal of Gastroenterology 2013;19(4):7804‐12. [DOI] [PMC free article] [PubMed] [Google Scholar]