Chronic chest pain is a common complaint in primary care; it should always be treated with the greatest of concern, as several potentially lethal conditions may present in this manner. A careful history and examination is mandatory in these patients, with particular attention being paid to the possibility of ischemic heart disease (IHD). In this specific lady's case, her primary care physician appears to have already considered this fact; while she does possess a cardiac risk factor (hypertension), the non-anginal nature of the pain and normal exercise ECG make this possibility highly unlikely. In fact, the 'burning' nature of her pain is most suggestive of a gastrointestinal (GI) cause - particularly, gastroesophageal reflux disease (GERD). That said, the above is confounded by the lack of response to a course of proton pump inhibitors (PPIs); could it be an alternate GI etiology, such as a hiatus hernia? Close questioning reveals an even more important clue: recent-onset dysphagia to both solids and liquids; note that this favors an esophageal motility disorder. Achalasia is a possibility which immediately rises to mind; this presentation is characteristic of the condition. However, diffuse esophageal spasm can also present in this manner, as can pseudoachalasia. Further evaluation is mandatory, with upper GI endoscopy being a suitable first test. This reveals no esophageal or gastric lesions, although the gastroesophageal junction (GEJ) is difficult to traverse. Esophageal manometry should follow; this reveals aperistalsis and incomplete lower esophageal sphincter (LES) relaxation, two findings highly suggestive of achalasia. A barium swallow is also advisable, with the findings seen here supporting the diagnosis; this will also provide an objective measurement of the degree of esophageal emptying, which will help in the further management. Note that the age of the patient, relatively short duration of dysphagia, and difficulty in traversing the GEJ raise the possibility of pseudoachalasia (which is caused by primary or metastatic neoplasms at the level of the cardia); thus further evaluation via imaging of the abdomen is mandatory. However, a CT scan of the abdomen turns out to be normal, excluding this possibility; thus, achalasia is indeed the diagnosis. Graded pneumatic dilatation (PD) is a suitable treatment option in this case. Esophagectomy is mainly an option in late-stage achalasia (e.g. megaesophagus formation). Note that both injection of Botulinum Toxin and administration of calcium-channel inhibitors have only limited efficacy, and are only indicated in patients who are not candidates for definitive therapy.
Achalasia (which means 'failure to relax' in Greek) is a primary esophageal motor disorder of unknown etiology; it is characterized by insufficient relaxation of the lower esophageal sphincter (LES), and loss of esophageal peristalsis. The condition occurs equally in both genders, and is found across all races, with a prevalence of up to 1 in 10,000 persons. While most cases are idiopathic, achalasia has been reported in association with malignancy, and as part of the spectrum of Chagas disease; rarely, it may be familial. To appreciate the pathophysiology of achalasia, one must first recall that both excitatory and inhibitory impulses from neurons play a role in maintaining esophageal tone and motility. Most of the time, excitatory impulses predominate, and the muscles of the esophagus lie in a contractile state. However, during deglutition, inhibitory neurons override this effect, resulting in relaxation. In individuals with achalasia, there is failure of the above inhibitory innervation, most likely due to the loss of inhibitory neurons in the myenteric plexus; the end result is reduced relaxation of the LES, and impaired peristalsis. Dysphagia is a cardinal sign of the condition; in the early stages, this may be very subtle, but as the disease advances, overt difficulty in swallowing both solids and liquids occurs. As a result of stasis and retention of food and liquids in the esophagus, weight loss, chest pain, regurgitation, and a nocturnal cough (due to aspiration) are frequently reported; this may potentially lead to misdiagnosis as gastro-esophageal reflux disease (GERD). Heartburn is also common, and may be due to retention of acidic or noxious food contents, or because of lactate production from bacterial fermentation within the esophagus. Hiccups may occur, and are probably due to esophageal distention, and stimulation of afferent vagal fibers. Where achalasia is suspected clinically, this should be confirmed via investigations; esophageal manometry is the gold standard diagnostic test in this respect, while both upper gastrointestinal endoscopy (UGIE) and barium swallows play a further supportive role. Until fairly recently, conventional manometry (CM) was the only manometric technique widely available. However, many centers now offer high-resolution manometry (HRM), which is more sensitive, specific, and easier to perform. Aperistalsis, and incomplete relaxation of the LES are the two key manometric findings suggestive of achalasia; the presence of an increased basal LES pressure, elevated baseline esophageal body pressure, and simultaneous non propagating contractions may provide further supportive evidence. Note that based on information provided by HRM (but not CM), achalasia can be divided into 3 different subtypes; this is helpful in determining the management, and gauging the likely prognosis. UGIE is mainly of use in ruling out a mechanical obstruction or pseudoachalasia, as both of these conditions can mimic achalasia clinically and manometrically. Furthermore, in patients who are misdiagnosed as having GERD, endoscopy may help suggest the presence of achalasia by demonstrating findings such as a dilated esophagus with retained food or saliva, and a puckered gastroesophageal junction. Barium swallows can also help guide the diagnosis towards achalasia; supportive findings in this respect include dilation of the esophagus, a narrow esophagogastric junction (EGJ) with a "bird beak" appearance, aperistalsis, and poor emptying of barium. They are also of use in the further management, by demonstrating late changes (e.g. tortuosity, angulation, megaesophagus), as well as in providing objective assessment of esophageal emptying after therapy. It should be reiterated that both UGIE and barium swallows are not diagnostic of achalasia, and are not sufficiently sensitive for a negative result to rule out the condition. Unfortunately, achalasia cannot be cured; treatments (which may be surgical or non-surgical) are aimed at reducing the hypertonicity of the LES, thus relieving symptoms, improving esophageal emptying, and preventing further dilation of the esophagus. Pneumatic dilation (PD) is the most effective nonsurgical technique; this uses air pressure to intraluminally dilate and disrupt the LES. Note that as esophageal perforation is a potential complication of PD, these patients should be capable of undergoing surgery if necessary. Surgical techniques include myotomy of the LES; while initially performed via thoracotomy or a transabdominal approach, this is now mostly conducted via minimally invasive techniques. Almost one-third of patients develop GERD following myotomy; thus, the most recent guidelines from the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) recommend that these patients should also undergo fundoplication, so as to prevent reflux. Studies have shown that in expert hands, both PD and myotomy have comparable success rates; however, at the time of writing, relatively few centers have significant expertise with PD, although this number is rapidly increasing. Note also that peroral esophageal myotomy (POEM), a recently developed endoscopic technique for the treatment of achalasia, appears to show good results, with success rates of over 90%. However, there is still scant evidence comparing POEM with PD and laparoscopic myotomy; thus, it is still only performed in the context of clinical trials, in centers with expertise with the technique. Pharmacologic therapies (such as injection of botulinum toxin) show only limited success and are best reserved for individuals who cannot undergo PD or surgical intervention. It is important to appreciate that none of the above interventions significantly affect esophageal peristalsis; furthermore, the LES hypertonicity eventually returns over time, requiring repeat treatment. Thus, these patients require regular follow up; symptomatic and objective testing with barium swallows at regularly scheduled intervals may be needed to avoid end-stage achalasia and/or megaesophagus. Another point to note is that as achalasia impairs esophageal emptying, these patients are at increased risk of developing cancer of the esophagus. However, routine screening in this respect is controversial, as the overall number of cancers remains low, and estimates have suggested that over 400 endoscopies would be required to detect one cancer; furthermore, survival of these patients is poor even if the diagnosis is made early on.