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Ann Thorac Surg 2005;80:1191-1195
© 2005 The Society of Thoracic Surgeons

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Original article: General thoracic

Laparoscopic Esophageal Myotomy for Achalasia: Factors Affecting Functional Results

^a Division of General Thoracic Surgery, Mayo Clinic College of Medicine, Rochester, Minnesota
^b Section of Biostatistics, Mayo Clinic College of Medicine, Rochester, Minnesota

Accepted for publication April 4, 2005.

^_* Address reprint requests to Dr Deschamps, Division of General Thoracic Surgery, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (Email: deschamps.claude{at}mayo.edu).

Presented at the Forty-first Annual Meeting of The Society of Thoracic Surgeons, Tampa, FL, Jan 24–26, 2005.

	Abstract

Top Abstract Introduction Material and Methods Results Comment Discussion References

 
BACKGROUND: We reviewed our experience and analyzed factors affecting functional results after laparoscopic esophageal myotomy (LEM) for achalasia.

METHODS: From January 1996 through October 2003, the records of 211 patients (110 men and 101 women) who had LEM for achalasia were reviewed, and factors affecting morbidity and functional results were analyzed.

RESULTS: Median age was 47 years (range, 12 to 85). One hundred and twenty-five patients (59%) had prior esophageal dilatation and/or botulinum toxin injection and 19 (9%) had a prior myotomy. A partial fundoplication was performed in 198 patients (94%); posterior in 135 and anterior in 63. Median operative time was 208 minutes (range, 90 to 527). Intraoperative complications occurred in 37 patients (17.5%), and included mucosal perforation in 32, pneumothorax in 2, and retained needle, splenic capsular tear, and gastric short vessel bleeding in 1 each. Five patients (2%) required conversion to an open procedure. Postoperative complications occurred in 17 patients (8%) including 2 patients who required reoperation for leak. There were no perioperative deaths. Median hospitalization was 3 days (range, 1 to 48). Follow-up was complete in 167 patients (79%) and ranged from 1 to 70.5 months (median, 5.3). Functional results were classified as excellent in 105 patients (63%), good in 43 (26 %), and fair or poor in 19 (11%). Previous esophageal surgery for achalasia adversely affected functional results (p = 0.0139). Preoperative bougie dilatation (p = 0.9851), pneumatic dilatation (p = 0.8548), botulinum toxin injection (p = 0.1724), and the type of fundoplication (p = 0.5904) did not affect functional results. Preoperative bougie dilatation (p = 0.441), pneumatic dilatation (p = 0.1060), and botulinum toxin injection (p = 0.3938) did not affect the incidence of intraoperative perforation. As experience is gained, the incidence of intraoperative complications has decreased significantly (p = 0.0075).

CONCLUSIONS: Laparoscopic myotomy for achalasia is safe and effective in the majority of patients. The incidence of intraoperative complications decreases as experience is gained. Preoperative endoscopic treatment does not preclude successful surgical outcome. Excellent or good functional results are achieved in the majority of patients although previous surgical treatment adversely affects functional results.

	Introduction

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Laparoscopic esophageal myotomy (LEM) has become the standard surgical treatment for patients with achalasia [1–4]. Although LEM has been common for more than a decade, controversy still exists regarding the factors affecting functional results. The purpose of this report is to describe our experience with LEM in patients with achalasia and analyze factors affecting functional results.

	Material and Methods

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From January 1996 through October 2003, 214 patients with esophageal achalasia who underwent LEM at Mayo Clinic in Rochester, Minnesota, were reviewed. Three patients refused research authorization. The records of the remaining 211 patients were retrospectively analyzed for age, sex, symptoms, diagnostic evaluation, preoperative treatment, operative procedure, operative morbidity, and functional results. Follow-up information was collected at the outpatient clinic. Functional results were considered excellent if the patient was taking no medication and eating a general diet without symptoms; good if symptoms were minimal and medication or esophageal dilatation was not required; fair if symptoms were improved but medication or esophageal dilatation was required, and poor if symptoms were unchanged or worse. Descriptive statistics are reported using median and range. The association between potential risk factors and the functional results (excellent versus good versus fair or poor) was assessed using an extension of Fisher's exact test for ordered contingency tables [5]. Logistic regression was used to assess the association of the same risk factors with intraoperative morbidity. All statistical tests were two-sided, and the alpha level was set at 0.05 for statistical significance. Mayo Foundation's Institutional Review Board approved this study.

	Results

Top Abstract Introduction Material and Methods Results Comment Discussion References

 
There were 211 patients (110 men and 101 women). Median age at the time of LEM was 47 years and ranged from 12 to 85 years. Symptoms were present in all patients and included dysphagia in 208 (99%), regurgitation in 150 (71%), heartburn in 93 (44%), chest pain in 68 (32%), aspiration or cough, or both, in 54 (26%), and other symptoms in 19 (9%). Median duration of symptoms before LEM was 35 months and ranged from 1 to 550 months. One hundred and twenty-two patients (58%) lost weight. Median weight loss was 23.5 kg. One hundred and seven patients (51%) were taking proton pump inhibitors, and 51 (24%) were taking oral nitrates or calcium channel blockers. One hundred and twenty-five (59%) had previous esophageal dilatation or botulinum toxin injection. Sixty-seven patients (32%) had pneumatic dilatation, 52 (28%) had botulinum toxin, and 47 (22%) had bougie dilatation. Nineteen patients (9%) had previous myotomy for achalasia. Median time interval between the first operation and repeat myotomy was 36 months (range, 3 to 418). Previous procedures included left thoracotomy and myotomy in 7 patients, laparoscopic myotomy and fundoplication in 5, laparoscopic myotomy alone in 4, thoracoscopic myotomy in 2, and laparotomy with myotomy and fundoplication in 1.

Esophageal motility was done in 193 patients (91%) and demonstrated incomplete or nonrelaxation of the lower esophageal sphincter pressure in all, absence of normal peristalsis in 170, and nonspecific changes in 23. An upper gastrointestinal barium swallow was performed in 200 patients (95%) and demonstrated mild dilatation in 132, moderate dilatation in 43, severe in 17, tapered termination of the distal esophagus ("bird beak") in 28, hiatal hernia in 4, epiphrenic diverticulum in 2, and Zenker's diverticulum in 1. Esophagogastroduodenoscopy was performed in 203 patients (96%). Findings included esophagitis in 12, Barrett's metaplasia in 2, hiatal hernia in 1, and nonspecific or normal in 188. Twenty-four hour esophageal pH monitoring was performed in 18 patients (8%); only 1 had an extended period of time where the pH was below 4.

The operation was performed with the patient in the dorsal lithotomy position. Pneumoperitoneum was instituted with CO₂ insufflation. Five ports (5 and 10 mm) were utilized, with the locations being in the supraumbilical, right flank, epigastrium, left subcostal, and left flank areas. A 30-degree Storz rigid laparoscope (Karl Storz, Tuttlingen, Germany) was placed through the supraumbilical port and the liver retractor through the right flank port. The surgeon utilized the epigastrium and the left subcostal ports to perform the operation while the assistant retracted the stomach through the left flank port. Based on surgeon choice, a robotic arm (Aesop; Computer Motion, Santa Barbara, CA) was used to manipulate the camera. The hepatogastric ligament was partially divided, and the crura were mobilized laterally and anteriorly. The phrenoesophageal membrane was divided, and the esophagogastric junction fat pad was removed with the Harmonic Scalpel LCS (Ultra Cision, Smithfield, Rhode Island). The myotomy was performed after a bougie had been positioned in the esophagus. The myotomy was performed with endoscissors and was extended for at least 2 cm onto the stomach and 6 to 8 cm cephalad. The divided edges of the esophageal muscle were reflected laterally to uncover 50% of the esophageal circumference. Intraoperative esophagogastroscopy was not used. Both vagus nerves were identified with minimal manipulation in all patients and were preserved during the operation. Short gastric vessels were divided if a partial posterior fundoplication was performed. Based on surgeon choice, a partial anterior or posterior fundoplication was performed. All ports were closed in layers under direct vision using nonabsorbable sutures. We do not routinely insert a nasogastric tube postoperatively. The patient was allowed to have a liquid diet the night of surgery.

Five patients (2%) were converted to an open procedure. Reasons for conversion included inadequate exposure in 3 patients, bleeding in 1, and the finding of an intraabdominal lymphoma in 1. A robotic arm was used to manipulate the camera in 78 patients (38%). A myotomy was performed in all 211 patients. Associate procedures included a partial posterior fundoplication in 135 patients, a partial anterior fundoplication in 63, hiatal hernia repair in 4, take down of a previous anterior fundoplication in 4, and a serosal Thal patch, umbilical hernia repair, and excision of a distal esophageal leiomyoma in 1 each. Median operative time was 208 minutes and ranged from 90 to 527 minutes.

Intraoperative complications occurred in 37 patients (17.5%) and postoperative complications, in 17 (8%; Table 1). Three patients required reoperation, which included laparotomy for leak at the myotomy site in 2 and laparoscopic retrieval of retained needle in 1. Median hospitalization was 3 days (range, 1 to 48). There were no operative deaths.

Additional esophageal procedures were required in 4 patients including laparotomy with takedown of the partial fundoplication for dysphagia in 2, laparotomy to add a partial fundoplication in 1, and laparotomy to repair a hiatal hernia in 1. Twelve patients underwent further endoscopic treatments including dilatation in 7 and botulinum toxin injection in 5.

Factors affecting the incidence of intraoperative perforation and functional results were analyzed. Previous esophageal surgery for achalasia adversely affected functional results (p = 0.0139). Preoperative bougie dilatation (p = 0.9851), pneumatic dilatation (p = 0.8548), botulinum toxin injection (p = 0.1724), and the type of fundoplication (p = 0.5904) did not affect functional results. Preoperative bougie dilatation (p = 0.441), pneumatic dilatation (p = 0.1060), and botulinum toxin injection (p = 0.3938) did not affect the incidence of intraoperative perforation. As experience is gained the incidence of intraoperative complications has decreased significantly (p = 0.0075; Table 3).

	Comment

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Heller's 1914 report describes a transabdominal double (anterior and posterior) vertical extramucosal esophagomyotomy in a 49-year-old man with a 30-year history of swallowing difficulties. The operation was a success initially; 8 years later, the patient was still improved but was eating slowly. To this day, the surgical treatment of achalasia is inspired directly by Heller's contribution, regardless of the surgical approach [6].

The goal of surgical treatment of achalasia is to provide long-term relief of dysphagia and prevent or minimize postoperative gastroesophageal reflux. The majority of our patients had either excellent or good functional outcome after LEM. Those results are similar to other comparable series [3, 7, 8].

Several factors potentially affecting the functional outcome of LEM have been studied [9–13]. They include previous nonsurgical treatment such as botulinum toxin injection and esophageal dilatation, the presence of dilated or tortuous esophageal body, sex, and resting pressures of the lower esophageal sphincter [14]. Age, sex, and the duration of preoperative symptoms did not influence the outcome of LEM in our series of patients. Because of tissue planes obliteration, injection of botulinum toxin might increase the technical difficulties and the potential risks of myotomy [15]. Our intraoperative perforation rate of 16% was not influenced by preoperative treatment with botulinum toxin injection or pneumatic dilatation. Other have reported similar findings [9, 11]. In addition, preoperative endoscopic treatment of any kind did not influence functional outcome. Nineteen patients in our group had prior myotomy for achalasia. We found that this subgroup did have worse functional results than the rest of our patient's population. This finding most likely reflects a more advanced stage of the disease [13].

While most surgeons agree that a partial fundoplication is superior to a total fundoplication in the presence of a myotomy [16], there is controversy as to whether the routine addition of an antireflux operation is justified [17, 18]. In addition, little information exists to guide the choice of anterior versus posterior partial fundoplication. Recently, Richards and colleagues [19] have shown in a prospective randomized study that the addition of a anterior partial fundoplication significantly decreases the incidence of postoperative gastroesophageal reflux, when compared with no fundoplication. Like others [20], we could not identify an impact of the type of fundoplication on postoperative functional results.

As with other surgical procedures, a period of learning is required. In the present study, the incidence of intraoperative complications decreased significantly overtime. We believe that our previous experience in laparoscopy for hiatal hernia repair and antireflux surgery [21, 22] has facilitated the transition to another minimally invasive approach.

While this study does represent one of the largest series of LEM reported, it has limitations. Our follow-up was complete in 80% of patients, but our median follow-up duration of 5 months is short. We believe that continued follow-up of these patients will provide further useful information on functional outcome.

In conclusion, laparoscopic myotomy for achalasia is safe and effective for the majority of patients. The incidence of intraoperative complications decreases as experience is gained. Preoperative endoscopic treatment does not preclude successful surgical outcome. Excellent or good functional results are achieved in the majority of patients, although previous surgical treatment adversely affects functional results.

	Discussion

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DR MEHDI FAKHRAI (Mission Hills, CA): You had 11% of patients who didn't have good results. Did you look at why they didn't have good results? Could it be that the extent of myotomy was not enough with the laparoscopy that you were doing, that you needed to do a more extended myotomy?

DR DEB: Some of these patients were patients who were undergoing a remyotomy after a previously failed myotomy. Our standard is to extend our myotomy 2 cm onto the cardia of the stomach. So I do not believe that an inadequate initial myotomy was the result for the poor results in those 11%.

DR MALCOLM M. DECAMP, JR. (Boston, MA): Congratulations on another superb series.

I wonder if you could comment a little bit more on the total denominator of patients with achalasia that you have seen. Are there patients that you would not recommend an attempt at a laparoscopic operation, specifically patients who have either had multiple previous procedures or sigmoid esophagus? Along those lines, would you also comment a little bit about your preoperative evaluation, your using routine manometry, barium swallow, timed barium swallows and things like that.

You know, speaking on behalf of Tom Rice from the Cleveland Clinic, we did find a higher incidence of intraoperative mucosal injuries that coursed very closely with the number of previous interventions, namely, pneumatic dilatation and Botox injections. So I think I have to congratulate you and Claude and the group at Mayo for overcoming those technical difficulties.

DR DEB: Thank you for those excellent questions.

I do not know the exact denominator in terms of all the patients that were evaluated for achalasia during this time period. Preoperative esophageal dilatation has been shown by Patti and others to not negatively influence the results of laparoscopic esophageal myotomy; that is, an esophageal diameter greater than 6 cm. In our series only 17 of our patients had, I would say, class III esophageal dilatation. We do not feel that that is a contraindication to offering a patient a laparoscopic esophageal myotomy.

In terms of previous therapies, Botox injections or dilatations, as I've shown, several of the patients had multiple episodes of those therapies. We do not feel that that is a contraindication as well to laparoscopic esophageal myotomy.

Lastly, we have looked at that subgroup of patients who have undergone previous surgery who subsequently reappear and need reintervention and underwent laparoscopic esophageal myotomy. We specifically looked at that subgroup that underwent laparoscopic esophageal myotomy and found that, although the results were not as good, those patients do benefit from a reattempt, a repeat laparoscopic esophageal myotomy.

In terms of the workup, we reserve the pH study primarily for patients who have severe symptoms of reflux. All patients get a barium esophagram and esophageal manometry and an esophagogastroduodenoscopy to rule out other disease.

DR WAYNE HOFSTETTER (Houston, TX): I would like to congratulate you on the series of patients that you presented. It's an extensive experience over a short period of time and shows that the learning curve can be overcome very quickly.

I have two questions and they basically reiterate what has been asked previously. I think that we learn the most from our failures, that 11% of patients in your series. Although it's a very small percentage of patients who went on to have a poor result from myotomy, we could learn specifically from that group of patients. Did you find that you used different selection criteria for myotomy after your learning curve had been accomplished; that those 11% of patients would have been better treated with either further dilatation or with esophagectomy? Did you modify your criteria for looking at the patients preoperatively? Over time, did you find that that failure rate decreased?

The second question, among the patients that you said were asymptomatic from heartburn postoperatively, and I've seen that you have a beautiful manometry lab there at Mayo, have you had a chance to look at the patients postoperatively for pH studies to confirm that those patients who are indeed asymptomatic are not having any reflux?

DR DEB: I'll answer the latter question first. The patients routinely do not undergo postoperative manometry studies if they are complaining of heartburn. Most of the data that I showed were subjective descriptions of heartburn symptoms that the patients described to their gastroenterologists on follow-up.

In terms of the 11% of patients who had poor results, we will need to look at those more closely. As I said, the majority of those patients had had previous surgery, and, as I said, they do benefit from a repeat attempt at myotomy. I would not recommend proceeding to an esophagectomy as therapy in a patient who has recurrent symptoms of dysphagia following laparoscopic or an open myotomy.

DR GAIL E. DARLING (Toronto, Ontario, Canada): I have a similar question, regarding your outcome data in terms of the symptomatic results. Did you use any validated symptom scores such as a dysphagia scores or quality of life indicators?

DR DEB: The functional results were deciphered from follow-up visits with gastroenterologists or the surgeon in terms of how the patient described their ability to swallow and whether they were on any medications. If a patient had no dysphagia, was eating a normal diet, that would be an excellent result. If they had occasional dysphagia, did not require any medication, that would be a good result.

DR DARLING: So it wasn't a systematic questionnaire?

DR DEB: We didn't use a standardized swallowing scale.

DR NICHOLAS J. DEMOS (Jersey City, NJ): I have to congratulate you on a wonderful, expert delivery of your paper. I have to ask you about hiatal hernia.

Mr Belsey has said repeatedly that 10% of those with achalasia have hiatal hernia. Would you comment on that, especially since you did a good number of pH studies on your patients. Next, almost a similar question as the first gentleman about megaesophagus with pronounced kinking at the esophagogastric junction, what do you do for that? Number three, have you compared your results with the superb results that Dr Ellis has reported with left thoracotomy for this?

DR DEB: There were some patients that were identified to have a hiatal hernia. I believe the number was around 10 patients among this series of patients who had the preoperative diagnosis of a hiatal hernia, and those were repaired at the time of myotomy. Postoperatively one patient did develop a hiatal hernia that required a reoperation on late follow-up. In terms of the megaesophagus, the size of the esophagus itself was not used as a contraindication to offering a patient laparoscopic myotomy. As I mentioned, Patti has shown that you can have equivalent, good results in those patients. We did not specifically look at the excellent results of Dr Ellis's open thoracotomy approach. Our results of overall success, about 89%, is comparable to most of the other larger series that have been reported where the range has been anywhere between 87% and 99%, and those are open as well as laparoscopic series.

	References

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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Subrato Deb Claude Deschamps Mark S. Allen Francis C. Nichols, III Stephen D. Cassivi Peter C. Pairolero Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Deb, S. Articles by Pairolero, P. C. Search for Related Content PubMed PubMed Citation Articles by Deb, S. Articles by Pairolero, P. C.