New technologies for the evaluation of esophageal motility disorders: impedance, high-resolution manometry, and intraluminal ultrasound

The level of impaired esophageal bolus transit measured by multichannel intraluminal impedance: Cross-sectional study

BACKGROUND

Esophageal motility disorders (EMDs) are often diagnosed manometrically, yet the underlying pathology is not always clear. Esophageal function testing (EFT), which incorporates manometry and multichannel intraluminal impedance (MII), is considered a useful tool in the assessment of EMDs.

OBJECTIVE

This study aims to assess the most likely level of impaired bolus transit within the esophagus which may help further localize and characterize EMDs.

METHODS

In a retrospective study design, we reviewed consecutive EFTs over a period of 12 months. Data included diagnosis, presenting symptoms, and EFT results of liquid and viscous swallows. Each patient underwent 10 liquid and 10 viscous swallows, and bolus transit is measured at 5, 10, 15 and 20 cm above the gastroesophageal junction (GEJ). We recorded the initial level of impaired bolus transit for each swallow.

RESULTS

A total of 2358 swallows in 118 patients was included for analysis. Of these, 837 swallows (35.5%) were incompletely transmitted. The proportions of impaired bolus transit were 39%, 41%, 15.6%, 4.4% at 20 cm, 15 cm, 10 cm, and 5 cm above the GEJ, respectively. The common symptoms at presentation were dysphagia (47%), heartburn (44%), chest pain (24.6%) and regurgitation (18%). The mean lower esophageal sphincter (LES) pressure was 24 ± 13.9 mmHg whereas the mean contraction amplitude was 84 ± 46.6 mmHg.

CONCLUSION

In patients with abnormal esophageal clearance, the most likely levels of impaired bolus transit are 15 and 20 cm above the GEJ. These levels of the esophagus should be a focus of attention in future studies evaluating the pathophysiology of esophageal dysmotility.

EUS-guided FNA biopsy of the muscularis propria of the antrum in patients with gastroparesis is feasible and safe

BACKGROUND AND AIMS

EUS-guided FNA biopsies of the muscularis propria of the gastric wall in patients with gastroparesis could replace the routine use of surgical full-thickness biopsies for assessing the loss of the interstitial cells of Cajal (ICCs) and cellular infiltrates in the myenteric plexus. We investigated the efficacy and safety of EUS-guided FNA biopsies of the muscularis propria of the gastric antrum in gastroparesis and compared the tissue with a surgically obtained full-thickness biopsy specimen in the same patient.

METHODS

This was a prospective, nonrandomized, feasibility trial. Patients with gastroparesis who were undergoing gastric neurostimulator placement were enrolled. Patients had a gastric wall measurement by radial EUS in the body and antrum of the stomach followed by linear EUS examination and FNA of the muscularis propria in the antrum by using a 19-gauge core needle. Within 24 hours, a full-thickness biopsy specimen of the antrum was obtained surgically during neurostimulator placement. Endoscopic and surgical specimens were compared for tissue morphology, number of ICCs (c-kit stain) and enteric neurons (S-100 stain), and fibrosis (trichome) for each patient. The correlation coefficient of the ICC count per high-power field was used to compare both specimens. Continuous data were compared by using a t test.

RESULTS

Eleven patients (10 female, 1 male), with a mean age of 40.6 years, were enrolled in the trial. EUS-guided core biopsies were successful in obtaining sufficient tissue for the histologic assessment of ICCs in 9 patients (81%) and for the myenteric plexus in 6 patients (54%). There was a good correlation coefficient (0.65) when both surgical and endoscopic groups were compared for the loss of ICCs. Mild serosal bruising and/or localized hematoma formations were noted at the sites of EUS biopsies, but there were no serosal tears, perforations, or adverse effects on the hospitalization and outcomes.

CONCLUSIONS

EUS-guided FNA of the gastric muscularis propria in patients with gastroparesis is safe and provides adequate tissue for full histologic assessment. (Clinical trial registration number: NCT01916460.).

Characterization and follow-up of esophagogastric junction outflow obstruction detected by high resolution manometry

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) is a newly described diagnostic entity growing in importance due to the use of high resolution manometry (HRM). There is little knowledge regarding its incidence, etiopathogeny, long-term evolution, and most suitable treatment. Our objective was to increase the awareness of EGJOO to optimize the management of these patients.

METHODS

We conducted a historical (retrospective and prospective) study of patients diagnosed with EGJOO using HRM combined with multichannel intraluminal impedance, comparing their manometric and impedance characteristics with those of a control group. Symptoms, etiology of obstruction, acid exposure, clinical course (and its associated factors), and response to treatment were also evaluated in the EGJOO group.

KEY RESULTS

Forty-four subjects were included (28 patients and 16 controls). Esophagogastric junction outflow obstruction patients presented incomplete esophageal transit more frequently than controls. Patients with structural obstruction had dysphagia more frequently than patients with functional obstruction, and different manometric, impedance, and pH-metric patterns. Over one-third of the EGJOO patients presented a spontaneous resolution of symptoms without EGJOO treatment. In the multivariate analysis, the variables associated with this spontaneous symptomatic resolution included typical symptoms of gastro-esophageal reflux disease or epigastralgia as the main symptom and resting or basal pressure of the upper esophageal sphincter <50 mmHg.

CONCLUSIONS & INFERENCES

The majority of EGJOO patients presented intact peristalsis which may compensate for the lack of EGJ relaxation. In the EGJOO patients presenting favorable factors associated with a spontaneous resolution of symptoms, invasive treatments should be considered with special caution. Structural etiologies are more amenable to management, while the remainder may improve without intervention.

Effect of atilmotin, a motilin receptor agonist, on esophageal, lower esophageal sphincter, and gastric pressures

BACKGROUND

Motilin, an endogenous gastrointestinal (GI) hormone, increases upper gastrointestinal tract motility and is associated with phase III of the gastric migrating motor complex. The motilin receptor agonist, atilmotin, at doses of 6, 30 or 60 microg intravenously (IV), increases the early phase of gastric emptying. Prior studies at higher doses of 100-450 microg IV demonstrated that some subjects developed noncardiac chest pain.

AIMS

The aim of this study is to determine the effects of atilmotin on esophageal, lower esophageal sphincter (LES), and gastric contractility and the development of esophageal-related symptoms.

METHODS

Ten healthy volunteers underwent esophageal manometry to study the effects of atilmotin on upper GI motility. Five subjects were studied on three separate days following administration of saline placebo and subsequent IV bolus dose of atilmotin (6, 30 or 150 microg). Another five subjects were studied at the highest dose (150 microg).

RESULTS

Atilmotin at 150 microg increased proximal gastric pressure by 6.5 mmHg (P = 0.001 compared with placebo). Atilmotin increased LES pressure at all studied doses; LES pressure increased from 24 +/- 2 mmHg following placebo injection to 34 +/- 4 mmHg following a 30 microg dose of atilmotin (P = 0.007). In the esophagus, atilmotin increased the percentage of failed swallows at the highest dose studied. Failed swallows increased from 17 +/- 7% following placebo injection to 36 +/- 7% following a 150 microg dose of atilmotin (P = 0.016). Atilmotin decreased distal esophageal contractile amplitude only at the highest dose studied, from 69 +/- 8 mmHg (placebo) to 50 +/- 5 mmHg following 150 microg atilmotin (P = 0.018). There were no serious adverse effects or episodes of chest pain with atilmotin.

CONCLUSIONS

Atilmotin affects esophageal, LES, and gastric motility. LES and gastric pressures were increased, whereas there was disruption of esophageal peristalsis characterized by lower amplitude and failed contractions.

Regurgitation in healthy and non healthy infants

Uncomplicate regurgitation in otherwise healthy infants is not a disease. It consists of milk flow from mouth during or after feeding. Common causes include overfeeding, air swallowed during feeding, crying or coughing; physical exam is normal and weight gain is adequate. History and physical exam are diagnostic, and conservative therapy is recommended. Pathologic gastroesophageal reflux or gastroesophageal reflux disease refers to infants with regurgitation and vomiting associated with poor weight gain, respiratory symptoms, esophagitis. Reflux episodes occur most often during transient relaxations of the lower esophageal sphincter unaccompanied by swallowing, which permit gastric content to flow into the esophagus. A minor proportion of reflux episodes occurs when the lower esophageal sphincter fails to increase pressure during a sudden increase in intraabdominal pressure or when lower esophageal sphincter resting pressure is chronically reduced. Alterations in several protective mechanisms allow physiologic reflux to become gastroesophageal reflux disease; diagnostic approach is both clinical and instrumental: radiological series are useful to exclude anatomic abnormalities; pH-testing evaluates the quantity, frequency and duration of the acid reflux episodes; endoscopy and biopsy are performed in the case of esophagitis. Therapy with H2 receptor antagonists and proton pump inhibitors are suggested.

Selected interventions in nuclear medicine: gastrointestinal motor functions

The measurement of gastrointestinal functions by the use of scintigraphy is established in clinical practice and research. The most commonly used test is the gastric-emptying test, which is acknowledged as the gold standard to measure gastric motility and is conducted according to a consensus statement from the national nuclear medicine and motility societies. Other techniques are somewhat more esoteric (eg, measurement of gastric accommodation with single-photon emission computed tomography) or the scintigraphic approach is not the acknowledged gold standard (eg, colonic transit, rectoanal angle, and emptying, esophageal transit). The performance characteristics of many of the scintigraphic measurements have been published and the pros and cons established in the literature. Pharmacologic interventions may also be used during scintigraphy to aid in diagnosis and treatment. Gastrointestinal scintigraphy is an integral and important component of the assessment of gastrointestinal function.

Utility and standards in esophageal manometry

Esophageal manometry is a specialized procedure used to evaluate lower and upper esophageal sphincter pressure, esophageal body contraction amplitude, and peristaltic sequence. The procedure is clinically useful in evaluation of a patient with nonstructural dysphagia, unexplained or noncardiac chest pain, a compendium of symptoms suggested because of gastroesophageal reflux disease, and in the preoperative evaluation for antireflux surgery. Manometric findings in 95 normal subjects evenly distributed across age groups were reported in 1987, and are the values still used in our and most laboratories today. The subsequent review will offer our "view" on the clinical utility of esophageal manometry, on the basis of years of experience and performance techniques that have remained constant over decades.