Editing Oesophageal motility disorders (section)

=== '''Achalasia''' ===

*** Failure of LOS to relax       with swallowing, associated with lack of co-ordinated peristalsis in       distal oesophagus
*** '''Risk       factors'''
**** Usually diagnosed between        25-60yo
**** M:F equal
*** '''Aetiology'''
**** '''Primary'''
***** Unknown aetiology
***** Possibly autoimmune -         possibly triggered by a virus, possibly HSV-1
**** '''Secondary''' (or more accurately,        diseases that can produce manometry findings similar to primary        achalasia)
***** Chagas disease (infection         with protozoan parasite ''Trypanosoma cruzi'', common in Central/South         America)
***** Malignancy
***** Amyloidosis
***** Neurofibromatosis
***** Eosinophilic oesophagitis
***** MEN 2B
***** Juvenile Sjogren's         syndrome
***** Chronic idiopathic         intestinal pseudo-obstruction
***** Anderson-Fabry disease
*** '''Pathophysiology'''       (of primary       achalasia)
**** Degeneration of ganglion        cells in the myenteric plexus in the oesophageal wall. Leads to reduced        neuromuscular function of the oesophagus, possibly secondary to        destruction of nerves to LOS
**** Loss of inhibitory neurons        is especially important
**** Oesophageal dilation is a        result of chronic obstruction and compensatory remodelling. This is a        sign of more advanced disease
**** Subtle impaired upper        oesophageal sphincter relaxation is also often seen
**** Histologic examination        reveals decreased numbers of neurons, and those that remain are        surrounded by inflammation
**** Increased risk of SCC, but        not by very much, 3% over 13 years in one series
*** '''Presentation'''
**** Insidious onset
**** Classic triad - dysphagia        (91%), regurgitation (90%), weight loss
**** Also heartburn,        post-prandial choking and nocturnal coughing
**** Dysphagia often begins        with liquids and progresses to solids
**** Recurrent aspiration -        pneumonia, lung abscess, bronchiectasis
**** Severity assessed using        Eckardt score (dysphagia, regurgitation, retrosternal pain, weight loss        rated 0-3)
*** '''Natural       history'''
**** Late disease characterised        by very dilated oesophagus
*** '''Diagnosis'''
**** Manometry
***** Elevated integrated         relaxation pressure >=15mmHg and absence of normal peristalsis
***** Type I (classic): 100%         failed peristalsis as indicated by a distal contractile integral         <100mmHg/s/cm, and without pan-oesophageal pressurisation
***** Type II: 100% failed         peristalsis and pan-oesophageal pressurisation seen in >20% of         swallows
***** Type III (spastic): no         normal peristalsis and premature contractions with distal latency         <4.5s and DCI>450mmHg/s/cm seen in >20% of swallows
**** Barium swallow - bird's        beak, sphincter spasm with delayed emptying, dilatation of oesophageal        body, lack of peristaltic waves in the body and failure of relaxation        of LOS
**** Gastroscopy - rule out        pseudoachalasia - GOJ tumours, neuropathy, strictures. Note 'popping'        feeling as you pass through LOS.
***** Can use the 'Content,         Anatomy, Resistance and Stasis' (CARS) score - which I can't find         online in July 2024
****


'''Classification     based on area of achalasia''' ("Chicago classification" - v4.0 is latest     (2020))

** Cannot be applied to people      with previous foregut surgery
** Type I - minimal oesophageal      function, dilated oesophagus, bird's beak
***

* Type II
** Absence of peristalsis,      bird's beak
** Best response to treatment
**
* Type III
** Impaired LOS relaxation but      also uncoordinated spastic activity in distal 2/3 of oesophageal body -      corkscrew appearance on oesophagram. Swallow results in      lumen-obliterating spasms. Chest pain often prominent.
** Endoscopic myotomy preferred
**

* '''Management'''
** Goals: treatment is directed      at relieving the obstruction in LOS - doesn't address the decreased      motility in the oesophageal body - therefore all are palliative
** Outcomes are best in type II      achalasia; however, no treatment can fix the underlying issue
** '''Treatment      approach by achalasia subtype'''
*** Type I and II: myotomy       (surgical or POEM), or balloon dilation
*** Type III: POEM (since can       do a longer myotomy)
*** If not a surgical candidate       can do botox
*** If can't even do botox,       medical therapy
** '''Medical''' - note these therapies are      really only limited to patients who cannot have more invasive techniques
*** Nitrates
**** Isosorbide mononitrate,        5-10mg, 15mins prior to meals
*** CCBs
**** Nifedipine 10-30mg 30mins        prior to meals
*** Phosphodiesterase-5       inhibitors
**** Sildenafil
** '''Endoscopic'''
*** Botulinum toxin 100U Botox       A injected into four quadrants just above Z-line
**** Wears off after three        months
**** Response worsens within a        year
**** Limited use to patients        who are not candidates for pneumatic dilation or Heller myotomy
**** 89% remission at one year        with balloon dilatation, compared with 38% with botox
*** Pneumatic dilatation
**** Balloon device (30, 35 or        40mm) placed across LOS and inflated to 7-15psi until waist is fully        flattened, and held for 15-60 seconds
**** Graded approach is best
**** Look out for occult        perforation - barium swallow if worried
**** GORD happens 15-30% of        patients post-dilation - give PPI
**** Frequently requires        multiple treatments
*** Per-oral endoscopic myotomy
**** Novel technique
**** Equivalent short-term        outcomes to myotomy
**** Divide muscular layer of        the distal oesophagus, LOS and cardia. Good results in short-term, but        unclear if these will be durable.
***** POEM has also shown good         results for sigmoid oesophagus
** '''Surgical:'''
*** Modified Heller myotomy -       good, durable results
**** 5cm proximal to GOJ, 3cm        distal
**** EATI trial - pneumatic        dilatation and lap Heller myotomy had roughly equivalent results at two        years, although 25% of dilatation patients needed repeat treatments
**** Addition of a partial        antireflux procedure (Toupet/Dor) is controversial but probably        warranted
*** Oesophagectomy for       megaoesophagus, sigmoid oesophagus, failure of more than one myotomy, or       reflux stricture not amenable to dilatation
**** Can be a transhiatal        oesophagectomy in most patients, but total oesophagectomy with        trans-thoracic dissection may be warranted in the setting of        mega-oesophagus
** Surveillance
*** Regular gastroscopy       recommended to exclude carcinoma