Review questions
1) Does the addition of a stomach wrap around the food pipe (oesophagus) reduce the backflow of food and acid from the stomach to the food pipe (regurgitation) when used with keyhole surgery to treat achalasia?
2) Which type of stomach wrap (partial or total) around the food pipe is better at controlling regurgitation without causing difficulty in swallowing (dysphagia) when used with keyhole surgery to treat achalasia?
Background
Achalasia is a rare disease caused by a permanent state of contraction of a valve (lower oesophageal sphincter) at the lower end of the food pipe. It causes difficulty in swallowing which can be relieved by keyhole surgery to divide the muscles (Heller's cardiomyotomy) of this valve. The function of this valve is to stop the regurgitation of food and acid (reflux) from the stomach to the food pipe. Dividing the muscles of this valve, as a treatment for achalasia, can lead to increased acid regurgitation. To prevent this regurgitation, some surgeons, wrap the upper part of the stomach around the lower end of the food pipe. This stomach wrap acts as an artificial sphincter preventing acid regurgitation. The role of this wrap in controlling regurgitation is not universally accepted by all surgeons, and there is also disagreement as to the type of wrap (partially attached to the front (anterior) or back (posterior) of the stomach, or completely encircling the stomach (total)) that is best at controlling regurgitation, without worsening the difficulty in swallowing.
Study characteristics
We only included studies where adults with achalasia are treated with keyhole surgery to divide the muscles of the valve at the lower end of the food pipe; studies used different types of stomach wraps or no wraps at all. In all these studies, the participants were allocated to a treatment group at random (randomised controlled trial) to ensure uniform representation and reduce any error due to prejudice (bias). Comparing the results of these different techniques, we have tried to find out if the addition of a stomach wrap helps to prevent acid regurgitation, and also the type of wrap that is better at controlling regurgitation. We searched three databases (CENTRAL, MEDLINE, Embase) on 31 October 2021 and the evidence provided is current to October 2021. We included eight studies in this review (a total of 571 participants). All participants underwent keyhole surgery to divide the muscles of the valve at the lower end of the food pipe. In addition, 298 participants had partial anterior (Dor) stomach wrap, 81 had partial posterior (Toupet) wrap, 72 had total (Nissen) wrap, and 55 had the stomach hitched to the food pipe (angle of His augmentation) with stitches, and 65 had no additional procedures.
Key results
The evidence is very uncertain whether or not the addition of a partial anterior (Dor) wrap makes a change to the outcomes of acid regurgitation and is uncertain for difficulty in swallowing in these participants. There seems to be no difference in the outcomes between the partial anterior (Dor) and partial posterior (Toupet) wraps in terms of acid regurgitation and difficulty in swallowing, but there is uncertainty about the evidence. The total (Nissen) wrap causes increased swallowing difficulties when compared to the partial anterior (Dor) wrap. The study comparing partial anterior (Dor) wrap to a procedure where the stomach was simply hitched to the food pipe with a few stitches did not show any difference in difficulty of swallowing after the surgery, but did not report on acid regurgitation.
Certainty of evidence
All studies included in the review are well constructed. However, one study has only been published as an abstract, giving us limited information. The other limitations of this review are the small number of participants and short follow-up periods in the studies. There are also differences in defining, measuring and assessing the outcomes in these studies. We have assessed the overall certainty of evidence in this review as low.
When LHC was performed with minimal hiatal dissection, we were very uncertain whether the addition of a Dor fundoplication made a difference in controlling postoperative reflux, and we were uncertain if it increased the risk of severe postoperative dysphagia. There may be little to no difference in the outcomes of postoperative pathological acid reflux or severe dysphagia between Dor and Toupet fundoplications when used in combination with LHC, but the certainty of the evidence is low. Nissen (total) fundoplication used in combination with LHC for achalasia increased the risk of severe postoperative dysphagia. The angle of His accentuation and Dor fundoplication had a similar effect on severe postoperative dysphagia when combined with LHC, but their effect on postoperative pathological acid reflux was not reported.
Laparoscopic Heller’s cardiomyotomy (LHC) is the preferred treatment of achalasia. It improves dysphagia by dividing muscles of the lower oesophageal sphincter, but this intervention can result in debilitating gastro-oesophageal reflux symptoms in some patients. To prevent these reflux symptoms, most surgeons add a fundoplication to Heller’s cardiomyotomy, but there is no consensus regarding this or the type of fundoplication which is best suited for the purpose.
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.
We searched three databases (CENTRAL, MEDLINE and Embase) on 31 October 2021 and trial registers to identify all published and unpublished randomised controlled trials (RCTs) in any language, comparing different fundoplications used in combination with LHC to treat achalasia. We also included RCTs where LHC with a fundoplication is compared with LHC without any fundoplication.
We only included RCTs which recruited adult participants with achalasia undergoing LHC with minimal hiatal dissection. We excluded non-randomised studies or studies involving paediatric participants. We also excluded studies where the procedure was done by open surgery and where circumferential hiatal dissection of the oesophagus was carried out, unless it was necessary to reduce a hiatus hernia or to facilitate a Toupet or Nissen fundoplication.
Two review authors independently identified studies to be included, assessed risk of bias using the Cochrane RoB 1 tool, and extracted the data. We calculated the risk ratio (RR) with 95% confidence interval (CI) using both fixed-effect and random-effect models with Review Manager (RevMan) software.
We included eight studies in this review, with a total of 571 participants with an average age of 45 years (range 33.5 to 50). LHC without any fundoplication was performed in 65 (11.3%) participants, 298 (52.1%) had Dor fundoplication, 81 (14.1%) had Toupet fundoplication, 72 (12.6%) had Nissen's fundoplication, and 55 (9.6%) participants had angle of His accentuation.
Three studies with a total of 143 participants compared LHC + Dor to LHC without fundoplication. We found that the evidence is very uncertain as to whether the addition of a Dor fundoplication made any difference to the outcome of postoperative pathological acid reflux (RR 0.37, 95% CI 0.07 to 1.89; I2 = 56%; 2 studies, 97 participants; very low-certainty evidence) and uncertain for severe postoperative dysphagia (RR 3.00, 95% CI 0.34 to 26.33; I2 = 0%; 3 studies, 142 participants; low-certainty evidence).
Three studies with 174 participants compared LHC + Dor to LHC + Toupet. The evidence suggests that there may be little to no difference in the outcomes of postoperative pathological acid reflux (RR 0.75, 95% CI 0.23 to 2.43; I2 = 60%; 3 studies, 105 participants; low-certainty evidence) and severe postoperative dysphagia (RR 0.78, 95% CI 0.19 to 3.15; I2 = 0%; 3 studies, 123 participants; low-certainty evidence) between the two interventions, but the certainty of the evidence is low.
One study with 138 participants compared LHC + Dor to LHC + Nissen. Nissen fundoplication caused increased severe postoperative dysphagia (RR 0.19, 95% CI 0.04 to 0.83; 1 study, 138 participants; high-certainty evidence) when compared to Dor fundoplication. This study did not show a difference in postoperative pathological acid reflux (RR 4.72, 95% CI 0.23 to 96.59; 1 study, 138 participants; low-certainty evidence), but the certainty of evidence is low.
One study with 110 participants compared LHC + Dor with LCH + angle of His accentuation, and reported that severe postoperative dysphagia was similar between the two interventions (RR 1.56, 95% CI 0.27 to 8.95; 1 study, 110 participants; moderate-certainty evidence), with moderate certainty of evidence . This study did not report on postoperative pathological acid reflux.