What are the possibilities of misdiagnosis of achalasia before antireflux surgery?
C.G. Bremner (Los Angeles)
The principal symptoms of achalasia are dysphagia, regurgitation, weight loss and chest pain . The word "heartburn" is not mentioned as a symptom of achalasia in most descriptions or in most modern textbooks [1-3], but "pain" is reported to be present in 60% of patients. Altorki and Little , however, in Nyhus and Baker's second edition of "Masters of Surgery" mentioned that a few patients with achalasia have heartburn associated with a hiatal hernia with gastroesophageal reflux or retention esophagitis secondary to stasis. Hiatal hernia is present in approximately 4% of patients who have achalasia . Spechler et al. , recently reported on heartburn as a symptom in 32 untreated patients who had achalasia. They distinguished heartburn as a symptom separate from chest pain, and compared these patients with a group of 35 achalasic patients who did not have heartburn. Three of the patients who had heartburn also had histologically confirmed Barrett's esophagus. Three patterns of heartburn were observed in the group of 32 patients:
a) heartburn which followed the onset of dysphagia (8 patients),
b) heartburn which preceded the onset of dysphagia (15 patients) and heartburn which preceded the onset of dysphagia and stopped as the dysphagia progressed (9 patients).
Clearly, therefore, heartburn may be experienced in the symptom complex of achalasia. A retrosternal burning sensation may also be due to esophageal dysmotility, or may be due to retention of ingested acidic food or the generation of lactic acid in the process of decomposition of retained food. Furthermore, small quantities of acid reflux retained in the esophagus because of poor emptying and incomplete lower esophageal sphincter (LES) relaxation could cause heartburn. Spechler et al.  also suggest that achalasia may develop in the setting of gastroesophageal reflux disease (GERD). In fact LES function was low in their group of 15 patients who had the onset of heartburn before dysphagia developed.
It is not surprising therefore, that symptoms alone could mask the diagnosis of achalasia.
The fact that there are several reports in which inappropriate antireflux procedures have been performed for achalasia, stresses the need for a complete preoperative evaluation in all patients suspected of having GERD, particularly if dysphagia is an accompanying symptom.
Mattox et al.  warn that failure to obtain preoperative esophageal manometry in patients who are considered for antireflux surgery can result in immediate persistent postoperative dysphagia due to a missed diagnosis of achalasia. This was contrasted with a delayed onset of dysphagia due to a "slipped" Nissen fundoplication. Pneumatic dilation was used successfully to treat 2 of 3 cases of achalasia complicated by fundoplication in that series. The long-term outcome of a complete fundoplication performed after myotomy for achalasia is, however, unsatisfactory , and the same can be expected if pneumatic dilation is used in the presence of a total fundoplication because of progressive deterioration in the esophageal function.
Rosenzweig and Traube  reviewed the presentation of 25 patients who had a final diagnosis of achalasia. Achalasia was the initial diagnosis in only 12 of these patients. The others were diagnosed initially as GER , presbyesophagus , spasm , psychiatric disorders  and combinations of these disorders .
Gastroesophageal reflux (GER) has been described in patients who have achalasia . In two of Shoenut's patients a pH of less than 4 was present in 16.8% and 55.3% of the time, which was predictably influenced by supine reflux, because esophageal emptying was poor.
Smart et al.  recorded a high percentage of acid exposure time on pH monitoring in achalasia patients, but typical episodes of gastroesophageal reflux occurred in only one patient. The acid exposure clearly was due to retention of food in the esophagus resulting in a change in pH due to the lactic acidic change with decomposure of the food. Smart et al.  also reported on 5 patients who initially presented with symptomatic GER, proven by radiology or pH monitoring, who subsequently developed achalasia, confirmed on manometry and radiology, after an interval of 2-10 years. Of interest, reflux was not a problem after Rider-Moeller dilation or cardiomyotomy in these patients. They suggest that the autonomic damage eventually leading to achalasia may in its initial phases cause GER.
Achalasia may also mimic peptic esophageal stricture, and there is a report of 2 cases in which antireflux procedures were mistakenly performed when achalasia was present .
The author has been referred 7 patients who had a Nissen fundoplication performed on patients who had achalasia. Esophageal manometry had not been performed in any of these patients. The diagnosis of achalasia had been suggested by the radiologist in only one patient. Two patients referred to the author for esophageal manometry, had reflux symptoms and achalasia was not evident on the studies. One patient developed dysphagia after a Nissen fundoplication and manometric evidence of achalasia was present within a few months of the surgery. Dilatations were ineffective, leading to a reversal of the fundoplication and a esophagomyotomy. The second patient had a hypertensive relaxing LES and peristalsis. After one year of increasing dysphagia and a decrease in heartburn, a repeat manometric study confirmed all the classical features of achalasia.
Heartburn and GER may therefore accompany achalasia. Any suggestion of dysphagia should alert the clinician to the possibility of minimal achalasia. Esophageal manometry is mandatory in all patients with suspected GER. Failure to study these patients will inevitably lead to disastrous consequences.
7. Mattox HE, Albertson DA, Castell DO, Richter JE. Dysphagia following fundoplication: "slipped" fundoplication versus achalasia complicated by fundoplication. Am J Gastroenterology 1990;85:1468-1472.