Marcelo F. Vela

Guidelines for the diagnosis and management of gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) is arguably the most common disease encountered by the gastroenterologist. It is equally likely that the primary care providers will find that complaints related to reflux disease constitute a large proportion of their practice. The following guideline will provide an overview of GERD and its presentation, and recommendations for the approach to diagnosis and management of this common and important disease.

Acid and non-acid reflux in patients with persistent symptoms despite acid suppressive therapy. A multicentre study using combined ambulatory impedance-pH monitoring

Background and aims: Empiric proton pump inhibitor (PPI) trials have become increasingly popular leading to gastroenterologists frequently evaluating gastro-oesophageal reflux disease (GORD) patients only after they have “failed” PPI therapy. Combined multichannel intraluminal impedance and pH (MII-pH) monitoring has the ability to detect gastro-oesophageal reflux (GOR) episodes independent of their pH and evaluate the relationship between symptoms and all types of GOR. Using this technique, we aimed to characterise the frequency of acid and non-acid reflux (NAR) and their relationship to typical and atypical GOR symptoms in patients on PPI therapy. Methods: Patients with persistent GORD symptoms referred to three centres underwent 24 hour combined MII-pH monitoring while taking PPIs at least twice daily. Reflux episodes were detected by impedance channels located 3, 5, 7, 9, 15, and 17 cm above the lower oesophageal sphincter (LOS) and classified into acid or non-acid based on pH data from 5 cm above the LOS. A positive symptom index (SI) was declared if at least half of each specific symptom events were preceded by reflux episodes within five minutes. Results: A total of 168 patients (103 (61%) females and 65 (39%) males; mean age 53 (range 18–85) years) underwent combined MII-pH monitoring while taking PPIs at least twice daily. One hundred and forty four (86%) patients recorded symptoms during the study day and 24 (15%) patients had no symptoms during testing. Sixty nine (48%) symptomatic patients had a positive SI for at least one symptom (16 (11%) with acid reflux and 53 (37%) with NAR) and 75 (52%) had a negative SI. A total of 171 (57%) typical GORD symptoms were recorded, 19 (11%) had a positive SI for acid reflux, 52 (31%) for NAR, and 100 (58%) had a negative SI. One hundred and thirty one (43%) atypical symptoms were recorded, four (3%) had a positive SI for acid reflux, 25 (19%) had a positive SI for NAR, and 102 (78%) had a negative SI. Conclusion: Combined MII-pH identifies the relation of reflux of all types to persistent symptoms and the importance of NAR in patients taking PPIs.

Twenty-four hour ambulatory simultaneous impedance and pH monitoring: a multicenter report of normal values from 60 healthy volunteers.

OBJECTIVES:Impedance monitoring is a new diagnostic method for gastroesophageal reflux disease (GERD) where multiple impedance electrode pairs are placed on a standard pH catheter. It detects reflux of a liquid and/or gas bolus into the esophagus, as well as its distribution, composition, and clearing. The aim of this collaborative study is to define normal values for 24-h ambulatory simultaneous impedance and pH monitoring (24-h Imp-pH), and compare bolus parameters by impedance monitoring to changes in [H+] measured by pH monitoring.METHODS:Sixty normal volunteers without GER symptoms underwent 24-h Imp-pH with impedance measured at six sites (centered at 3, 5, 7, 9, 15, and 17 cm above lower esophageal sphincter) and pH 5 cm above the LES. Reflux detected by impedance was characterized by the pH probe as either acid, weakly acidic, nonacid, or superimposed acid reflux. Proximal reflux was defined as reflux that reached the impedance site 15 cm above the LES.RESULTS:Reflux frequency was common upright (median-27, 25th and 75th quartile-16, 42), but rare recumbent (median-1; 0, 4). A median of 34% (14%, 49%) of upright reflux reached the proximal esophagus. There was a similar number of mixed composition (liquid + gas; 49%) and liquid-only reflux (51%). Acid reflux was two-fold more common than weakly acidic reflux (p < 0.001). Superimposed acid reflux and nonacid reflux were rare. Acid neutralization to pH 4 took twice as long as volume clearance measured by impedance.CONCLUSIONS:Combining impedance and pH monitoring improves the detection and characterization of GER. This study characterizes the frequency, duration, and extent of reflux in health and provides normal values for 24-h Imp-pH for future comparison with GERD patients.

Baclofen decreases acid and non-acid post-prandial gastro-oesophageal reflux measured by combined multichannel intraluminal impedance and pH

Background : Omeprazole controls acid but not non‐acid reflux. The GABA B agonist baclofen decreases acid reflux through the inhibition of transient lower oesophageal sphincter relaxations (TLESRs) and should similarly decrease non‐acid reflux. Using combined multichannel intraluminal impedance and pH (MII/pH), we compared acid and non‐acid reflux after placebo and baclofen.

ACG Clinical Guideline: Diagnosis and Management of Achalasia

Achalasia is a primary motor disorder of the esophagus characterized by insufficient lower esophageal sphincter relaxation and loss of esophageal peristalsis. This results in patients’ complaints of dysphagia to solids and liquids, regurgitation, and occasional chest pain with or without weight loss. Endoscopic finding of retained saliva with puckered gastroesophageal junction or barium swallow showing dilated esophagus with birds beaking in a symptomatic patient should prompt appropriate diagnostic and therapeutic strategies. In this ACG guideline the authors present an evidence-based approach in patients with achalasia based on a comprehensive review of the pertinent evidence and examination of relevant published data.

Prevention and management of gastroesophageal varices and variceal hemorrhage in cirrhosis

Prevention and Management of Gastroesophageal Varices and Variceal Hemorrhage in Cirrhosis Guadalupe Garcia-Tsao, M.D.,1 Arun J. Sanyal, M.D.,2 Norman D. Grace, M.D., FACG,3 William D. Carey, M.D., MACG,4 the Practice Guidelines Committee of the American Association for the Study of Liver Diseases and the Practice Parameters Committee of the American College of Gastroenterology 1Section of Digestive Diseases, Yale University School of Medicine and VA-CT Healthcare System, New Haven, Connecticut; 2Division of Gastroenterology, Virginia Commonwealth University Medical Center, Richmond, Virginia; 3Division of Gastroenterology, Brigham and Women’s Hospital, Boston, Massachusetts; 4The Cleveland Clinic, Cleveland, Ohio

The Long-term Efficacy of Pneumatic Dilatation and Heller Myotomy for the Treatment of Achalasia

BACKGROUND & AIMS Studies comparing long-term success after pneumatic dilatation (PD) and laparoscopic Heller myotomy (HM) are lacking. This study compares long-term outcome of PD (single dilatation and graded approach) and laparoscopic HM and identifies risk factors for treatment failure. METHODS A cross-sectional follow-up evaluation of an achalasia cohort treated between 1994 and 2002 was followed-up for a mean of 3.1 years. There was a total of 106 patients treated by graded PD (1-3 dilatations with progressively larger balloons) and 73 patients treated by HM (20 had failed graded PD and crossed over to HM). A symptom assessment (structured telephone interview or clinic visit) was performed and patients were given freedom from alternative therapies to determine treatment outcome. Endoscopy, manometry, and timed barium esophagram were performed to determine the cause of treatment failure. RESULTS The success of single PD was defined as freedom from additional PDs: 62% at 6 months and 28% at 6 years (risk factors for failure: younger age, male sex, wider esophagus, and poor emptying on posttreatment timed barium esophagram). Freedom from subsequent PDs increased with each dilatation (graded PD). The success of graded PD and HM, defined as dysphagia/regurgitation less than 3 times/wk or freedom from alternative treatment, was similar: 90% vs 89% at 6 months and 44% vs 57% at 6 years (no risk factors for failure were identified). Causes of symptom recurrence were incompletely treated achalasia (96% after PD vs 64% after HM) and gastroesophageal reflux disease (4% after PD vs 36% after HM). CONCLUSIONS No treatment cures achalasia. Short- and long-term success is similar for graded PD and laparoscopic HM. Therapeutic success decreases steadily over time. Achalasia patients need careful long-term follow-up evaluation.

Esophageal function testing with combined multichannel intraluminal impedance and manometry: multicenter study in healthy volunteers.

BACKGROUND & AIMS Combined multichannel intraluminal impedance and manometry (MII-EM) assesses esophageal function by simultaneous measurement of both pressure and bolus transit. Normative data for this method have not been published. The aim of this study was to establish normative data for combined MII-EM and to correlate liquid and viscous bolus transit by impedance with esophageal contractions by manometry. METHODS Forty-three normal volunteers recruited from 4 centers (15 women, 28 men; age range, 21-72 years) underwent combined MII-EM with a catheter containing 4 impedance-measuring segments and 4 solid-state pressure transducers. Each center recruited and analyzed subjects independently, according to pre-established criteria. Each subject received 20 x 5 mL swallows, 10 liquid and 10 viscous material. Tracings were analyzed manually for bolus presence time, bolus head advance time, segmental transit times, total bolus transit time, contraction amplitude, duration, and onset velocity. RESULTS Ninety-seven and four-tenths percent of manometrically normal liquid and 96.1% of manometrically normal viscous swallows had complete bolus transit by impedance. Almost half (47.2%) of manometrically ineffective liquid and 34.7% of ineffective viscous swallows had complete bolus transit, whereas 91.7% of manometric simultaneous liquid swallows and 54.5% of simultaneous viscous swallows had complete bolus transit. More than 93% of normal individuals had at least 80% complete liquid or at least 70% complete viscous bolus transit. CONCLUSIONS This study establishes normative data for combined MII-EM. Combined MII-EM may be a more sensitive tool in assessing esophageal function compared to standard manometry because impedance can distinguish different bolus transit patterns. Studies in patients with manometrically defined esophageal motility abnormalities should help clarify the functional importance of manometric ineffective and simultaneous swallows.

Multichannel intraluminal impedance in esophageal function testing and gastroesophageal reflux monitoring

Multichannel intraluminal impedance (MII) is a new technique for evaluating esophageal function and gastroesophageal reflux. This technique depends on changes in resistance to alternating current between two metal electrodes produced by the presence of bolus inside the esophageal lumen. Combined MII and manometry (MII-EM) provides simultaneous information on intraluminal pressure changes and bolus movement, whereas combined MII and pH (MII-pH) allows detection of pH episodes irrespective of their pH values (ie, acid and non-acid reflux). Combined MII-EM studies are performed very similarly to standard manometry. Based on studies in healthy volunteers and patients, combined MII-EM challenges current existing criteria that define the effectiveness of esophageal body function. Combined MII-pH testing brings a shift in gastroesophageal reflux testing paradigm. In MII-pH studies, reflux events are no longer detected by pH. Refluxate presence, distribution, and clearing are primarily detected by MII and simply characterized as acid versus non-acid based on pH change and as liquid, gas, or mixed based on MII. MII determines refluxate clearance time, whereas pH measures acid clearance time. MII-pH shows promise to become an important clinical tool, particularly to assess gastroesophageal reflux in the postprandial period and in patients with persistent symptoms on therapy and with atypical symptoms.

Characteristics of Symptomatic Reflux Episodes on Acid Suppressive Therapy

BACKGROUND:Persistent symptoms on acid suppressive therapy are due to either acid or nonacid gastroesophageal reflux (GER) episodes or are not related to reflux.AIM:To compare physical and chemical characteristics of GER episodes associated with symptoms in patients on acid suppressive therapy.METHODS:Patients with persistent symptoms on acid suppressive therapy underwent combined impedance-pH monitoring. Reflux episodes were classified as acid if nadir pH was <4.0, and nonacid if it remained at ≥4.0, separated into liquid-only or mixed (liquid-gas), and considered to reach the proximal esophagus if liquid was present 15 cm above the lower esophageal sphincter (LES). Reflux episodes were considered symptomatic if patients recorded a symptom within 5 min after the reflux episode. Risk factors of symptomatic reflux episodes were identified using multivariable generalized estimating equations (GEEs).RESULTS:One hundred twenty patients (85 women, median age 54 yr, range 18–85 yr) recorded 3,547 reflux episodes (84.3% nonacid, 50.6% mixed), of which 468 (13.2%) were symptomatic. Based on multivariable GEE analysis with episode-level symptom status (symptomatic vs nonsymptomatic) as the outcome variable, reflux episode acidity was not significantly associated with symptoms (P = 0.40). Mixed reflux episodes were significantly associated with symptoms relative to liquid-only episodes (odds ratio [OR] 1.49, 95% confidence interval [CI] 1.19–1.87, P = 0.0005), as were reflux episodes reaching the proximal esophagus compared with those reaching the distal esophagus only (OR 1.28, 95% CI 1.06–1.55, P = 0.012).CONCLUSION:The majority of reflux episodes on acid suppressive therapy are asymptomatic. Reflux episodes extending proximally and having a mixed (liquid-gas) composition are significantly associated with symptoms, irrespective of whether pH is acid (<4) or nonacid (≥4).