Achalasia is a swallowing disorder caused by loss of function in the lower esophageal sphincter (the muscular ring at the junction of the esophagus and the stomach). Normally, when people swallow, the sphincter relaxes to allow food and liquid to pass into the stomach. With achalasia, the sphincter does not relax, which causes food to be lodged in that area.
Why esophageal muscles fail to contract normally in people with motility disorders, including achalasia, is unknown. Researchers think it may be linked to a virus and recent studies show achalasia is caused by nerve cells of the involuntary nervous system within the muscle layers of the esophagus. They are attacked by the patient’s own immune system and slowly degenerate for reasons that are not currently understood.
The main symptoms of achalasia include:
The symptoms of achalasia (difficulty swallowing, regurgitation, chest pain) are not specific to achalasia. Specific tests are needed to differentiate achalasia from other disorders including gastroesophageal reflux, tumors or cancers, benign strictures, inflammatory or allergic conditions, infections, and other diseases.
Three tests are most commonly used to diagnose the disease:
Treatments for achalasia include oral medications, stretching of the lower esophageal sphincter (dilation), surgery to cut the sphincter (esophagomyotomy), and the injection of botulinum toxin (Botox) into the sphincter. All four treatments reduce the pressure within the lower esophageal sphincter to allow easier passage of food from the esophagus into the stomach.
Oral medications that help to relax the lower esophageal sphincter include nitrates (isosorbide dinitrate) and calcium channel blockers (nifedipine, verapamil, diltiazem). By themselves, oral medications are likely to provide only short-term relief of the symptoms, and many patients experience side-effects from the medications.
Another treatment for achalasia is the endoscopic injection of botulinum toxin into the lower sphincter to weaken it. Injection is quick, nonsurgical, and requires no hospitalization.
Treatment with botulinum toxin is safe, but the effects on the sphincter often last only for months and additional injections with botulinum toxin may be necessary. Injection is a good option for patients who are very elderly or are at high risk for surgery, for example, patients with severe heart or lung disease. It also allows patients who have lost substantial weight to eat and improve their nutritional status prior to "permanent" treatment with surgery. This may reduce post-surgical complications.
Occasionally, achalasia can be treated non-surgically with balloon (pneumatic) dilation. Dilation is a quick and inexpensive procedure and requires only a short hospital stay. While the patient is under light sedation, the gastroenterologist inserts a specially designed balloon through the lower esophageal sphincter and inflates it. The balloon disrupts the esophageal muscle and widens the opening for food to enter the stomach. Some patients may have to undergo repeated dilation treatments in order to achieve symptom improvement, and the treatment may have to be repeated every few years to ensure long-term results.nother treatment for achalasia is the endoscopic injection of botulinum toxin into the lower sphincter to weaken it. Injection is quick, nonsurgical, and requires no hospitalization.
On average, this procedure offers a 75 percent chance of relieving symptoms for a period of years. Risk associated with the procedure, however, is potential perforation of the esophagus, which occurs 5% of the time. Half of the ruptures heal without surgery, though patients with rupture who do not require surgery should be followed closely and treated with antibiotics. The other half of ruptures require surgery.
It is thought that the most effective and durable treatment for achalasia is cutting the muscle, a procedure called esophagomyotomy. This can be accomplished surgically (referred to as Heller myotomy) or endoscopically (referred to as Per-oral endoscopic myotomy or POEM).
Heller myotomy is a well-established surgical procedure to treat achalasia that is usually performed laparoscopically. The surgeon finds the GEJ and cuts the abnormal muscle spanning part of the upper stomach, the LES, and the lower esophagus. This is often accompanied with an antireflux procedure (Nissen fundoplication) to partially reinforce the valve that has been disrupted at the GEJ.
POEM stands for "Per-oral endoscopic myotomy" and means cutting the muscle through the mouth with an endoscope. It is an incision-less endoscopic procedure that aims to recreate the Heller myotomy in a less invasive way. It follows similar surgical principles but is able to accomplish the myotomy less invasively. The procedure depends on recognition and utilization of the layers of the esophagus. These layers can be separated from each other like the layers of an onion.
POEM may be the best treatment option because it allows precise tailoring of the myotomy length in the esophagus as much as is needed to alleviate spasm and give a better chance at symptoms resolution. POEM has a special advantage in cases of prior Heller myotomy. A minority of patients with achalasia will have either a failure of improvement or a recurrence of symptoms after Heller myotomy. POEM offers shorter hospital stay, less pain, and quicker return to usual activities.