Distension of the esophagogastric junction augments triggering of transient lower esophageal sphincter relaxation

Endoscope presence during endoluminal functional lumen imaging probe (FLIP) influences FLIP metrics in the evaluation of esophageal dysmotility

BACKGROUND

The functional lumen imaging probe (FLIP) system is an FDA-approved tool for dynamic evaluation of the esophagogastric junction (EGJ). Even though commercially available since 2009, FLIP utilization remains low, partly due to lack of consensus in methodology and interpretation. Therefore, we aimed to analyze the influence of concurrent endoscopy on FLIP measurements.

METHODS

In this single-center study, we reviewed data from 93 patients undergoing FLIP for symptomatic esophageal motility disorders between 2016 and 2018. During sedated endoscopy, we measured luminal values (distensibility, cross-sectional area (CSA), and balloon pressure) at the EGJ and distal esophagus using 30, 40, and 50 mL distension volumes, with and without concurrent endoscope presence. All recorded values were compared at the various distension volumes between the two measurements using a Wilcoxon rank sum test.

KEY RESULTS

There was a significant difference in distensibility and CSA with index distension volume (40 mL) at the EGJ comparing the two measurements: Lower median distensibility was 2.1 mm²  mm Hg^-1 in the group with concurrent inserted endoscope, respectively, 3.4 mm²  mm Hg^-1 without endoscope (P < .001), and median CSA was 86.0 resp. 110.0 mm² (P < .001). No significant difference could be found in the measurements of the distal esophagus.

CONCLUSIONS & INFERENCES

Our results show a significant difference in FLIP measurements with and without endoscope presence. This underlines the importance of establishing a consensus of a standardized FLIP protocol to define normal luminal values and guiding future FLIP diagnostic studies.

24-hour monitoring of transient lower esophageal sphincter relaxation events by long-term high-resolution impedance manometry in normal volunteers: The "mirror phenomenon"

BACKGROUND

The aim of this study was to investigate the frequency and circadian changes in transient lower esophageal sphincter relaxations (TLESRs) in normal volunteers using 24-hour high-resolution impedance manometry (HRIM).

METHODS

Fifteen volunteers underwent HRIM. TLESRs were recorded during the mealtime, 2-hour postprandial, daytime, and supine periods. The catheter was firmly secured to the nose, and subjects went home, ate normal meals, and continued routine daily activities.

KEY RESULTS

Successful recordings were obtained in 11 volunteers. Overall, 1083 TLESRs were documented; the average occurrence was 4.2/h, and the duration was 21.0 ± 5.2 seconds. The majority of the TLESRs occurred during the 2-hour postprandial (42.7%) and daytime (31.5%) periods, while 10.2% and 15.6% occurred during the mealtime and supine periods, respectively. Eight hundred and eighty-six (81.8%) TLESRs were associated with reflux. Overall, 25.5% of TLESRs were preceded by partial secondary peristalsis (PSP), while 74.5% were preceded by nothing. Terminating events included primary peristalsis (PP; 40.3%), PSP (42.8%), full secondary peristalsis (FSP; 8.2%), or nothing (8.7%). Both preceding and terminating events periodically changed throughout the four periods. One hundred and twelve (10.3%) TLESRs with both preceding and terminating events of PSP, presenting as a "mirror phenomenon," were documented. The majority of these TLESRs occurred during the supine (70.5%).

CONCLUSIONS & INFERENCES

Transient lower esophageal sphincter relaxations are common physiological motor events in normal volunteers; these events have certain circadian rhythms, as do the events that precede and terminate TLESR events. A special "mirror phenomenon" is observed when both the preceding and terminating events are PSP.

Increase of transient lower esophageal sphincter relaxation associated with cascade stomach

We previously reported that cascade stomach was associated with reflux symptoms and esophagitis. Delayed gastric emptying has been believed to initiate transient lower esophageal sphincter relaxation (TLESR). We hypothesized that cascade stomach may be associated with frequent TLESR with delayed gastric emptying. Eleven subjects with cascade stomach and 11 subjects without cascade stomach were enrolled. Postprandial gastroesophageal manometry and gastric emptying using a continuous ¹³C breath system were measured simultaneously after a liquid test meal. TLESR events were counted in early period (0-60 min), late period (60-120 min), and total monitoring period. Three parameters of gastric emptying were calculated: the half emptying time, lag time, and gastric emptying coefficient. The median frequency of TLESR events in the cascade stomach and non-cascade stomach groups was 6.0 (median), 4.6 (interquartile range) vs 5.0, 3.0 in the early period, 5.0, 3.2 vs 3.0, 1.8 in the late period, and 10.0, 6.2 vs 8.0, 5.0 in the total monitoring period. TLESR events were significantly more frequent in the cascade stomach group during the late and total monitoring periods. In contrast, gastric emptying parameters showed no significant differences between the two groups. We concluded that TLESR events were significantly more frequent in persons with cascade stomach without delayed gastric emptying.

Studies on the regulation of transient lower esophageal sphincter relaxations (TLESRs) by acid in the esophagus and stomach

Transient lower esophageal sphincter relaxation (TLESR) is the major mechanism of gastroesophageal reflux, but the regulation of TLESR by stimuli in the esophagus is incompletely understood. We have recently reported that acid infusion in the esophagus substantially (by 75%) increased the number of meal-induced TLESR in healthy subjects. We concluded that the TLESR reflex triggered by gastric distention with meal was enhanced by the stimulation of esophageal nerves by acid. However, the possibilities that the acid infused into the esophagus acts after passing though lower esophageal sphincter in stomach to enhance TLESR, or that the acid directly initiates TLESR from the esophagus were not addressed. Here, we evaluated the effect of acid infusion into the proximal stomach on meal-induced TLESR (study 1) and the ability of acid infusion into the esophagus to initiate TLESR without prior meal (study 2). We analyzed TLESRs by using high-resolution manometry in healthy subjects in paired randomized studies. In study 1, we found that acid infusion into the proximal stomach did not affect TLESRs induced by standard meal. The number of meal-induced TLESRs following the acid infusion into the proximal stomach was similar to the number of meal-induced TLESRs following the control infusion. In study 2, we found that acid infusion into the esophagus without prior meal did not initiate TLESRs. We conclude that the increase in the meal-induced TLESRs by acid in the esophagus demonstrated in our previous study is not attributable to the action of acid in the stomach or to direct initiation of TLESR from the esophagus by acid. Our studies are consistent with the concept that the stimuli in the esophagus can influence TLESRs. The enhancement of TLESR by acid in the esophagus may contribute to pathogenesis of gastroesophageal reflux in some patients.

Unmet Needs in the Treatment of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a highly prevalent gastrointestinal disorder. Proton pump inhibitors have profoundly revolutionized the treatment of GERD. However, several areas of unmet need persist despite marked improvements in the ther-apeutic management of GERD. These include the advanced grades of erosive esophagitis, nonerosive reflux disease, main-tenance treatment of erosive esophagitis, refractory GERD, postprandial heartburn, atypical and extraesophageal manifestations of GERD, Barrett's esophagus, chronic protein pump inhibitor treatment, and post-bariatric surgery GERD. Consequently, any fu-ture development of novel therapeutic modalities for GERD (medical, endoscopic, or surgical), would likely focus on the afore-mentioned areas of unmet need.

Acid infusion into the esophagus increases the number of meal-induced transient lower esophageal sphincter relaxations (TLESRs) in healthy volunteers

BACKGROUND

Transient lower esophageal sphincter relaxation (TLESR) is the major mechanism of gastroesophageal reflux (GER) but the regulation of TLESR by stimuli in the esophagus is incompletely understood. If stimuli in the esophagus can influence TLESR, then such regulation may perpetuate or limit GER. We addressed the hypothesis that acid in the esophagus enhances TLESRs.

METHODS

We evaluated the effect of acid infusion into the distal esophagus on TLESRs evoked by a standard meal in a paired randomized study in healthy subjects. TLESRs were evaluated by using high resolution manometry (HRM).

KEY RESULTS

We found that acid in the esophagus enhanced meal-induced TLESRs. Compared to control infusion the number of TLESRs (median [interquartile range]) was increased during 2 h following the acid infusion (11 [9-14] vs 17 [12.5-20], p < 0.01). The average duration of individual TLESRs was not affected. The time-course analysis revealed that a robust increase in TLESRs occurred already in the first hour when the number of TLESRs nearly doubled (6 [5.5-7.5] vs 11 [7.5-12.5], p < 0.05). In contrast to the enhancement of TLESRs, the number of swallows was not changed.

CONCLUSIONS & INFERENCES

The acid infusion into the esophagus increases the number of meal-induced TLESRs in healthy subjects. Our results provide evidence for the concept that the stimuli in the esophagus can influence TLESRs. The regulation of TLESR by stimuli in the esophagus may contribute to pathogenesis of GER in some patients.

Management of paediatric GERD

Paediatric GERD is complicated to manage, as symptoms are diverse and often difficult to interpret. In infants, regurgitation is a common physiological condition. Nevertheless, when it occurs frequently (>4 times per day) and causes the infant distress, parents often seek medical help. In children 2-10 years of age, GERD is often considered to cause extra-oesophageal symptoms, despite the absence of hard evidence. Diagnostic investigations often lack solid validation and the signs and symptoms of GERD overlap with those of cow's milk protein allergy and eosinophillic oesophagitis. Reassurance, dietary treatment and positional adaptations are recommended for troublesome infant reflux. Anti-acid medication, mainly PPIs, is over-used in infants even though, in many children, reflux is not an acid-related condition. Moreover, evidence is increasing that PPIs cause adverse events such as gastroenteritis and respiratory tract infections. Management in children older than 10 years is similar to that in adults. Using prokinetics to treat nonerosive reflux disease remains only a promising theoretical concept, as no such molecule is currently available. Today, the adverse effects of each prokinetic molecule largely outweigh its potential benefit. Laparoscopic surgery is indicated in children who have life-threatening symptoms or in cases of drug dependence.

Effect of transoral incisionless fundoplication on reflux mechanisms

OBJECTIVES

Transoral incisionless fundoplication (TIF) is a new endoscopic treatment option for gastroesophageal reflux disease (GERD). The mechanisms underlying the anti-reflux effect of this new procedure have not been studied. We therefore conducted this explorative study to evaluate the effect of TIF on reflux mechanisms, focusing on transient lower esophageal sphincter relaxations (TLESRs) and esophagogastric junction (EGJ) distensibility.

METHODS

GERD patients (N = 15; 11 males, mean age 41 years, range 23-66), dissatisfied with medical treatment were studied before and 6 months after TIF. We performed 90-min postprandial combined high-resolution manometry and impedance-pH monitoring and an ambulatory 24-h pH-impedance monitoring. EGJ distensibility was evaluated using an endoscopic functional luminal imaging probe before and directly after the procedure.

RESULTS

TIF reduced the number of postprandial TLESRs (16.8 ± 1.5 vs. 9.2 ± 1.3; p < 0.01) and the number of postprandial TLESRs associated with reflux (11.1 ± 1.6 vs. 5.6 ± 0.6; p < 0.01), but the proportion of TLESRs associated with reflux was unaltered (67.6 ± 6.9 vs. 69.9 ± 6.3 %). TIF also led to a decrease in the number and proximal extent of reflux episodes and an improvement of acid exposure in the upright position; conversely, TIF had no effect on the number of gas reflux episodes. EGJ distensibility was reduced after the procedure (2.4 ± 0.3 vs. 1.6 ± 0.2 mm(2)/mmHg; p < 0.05).

CONCLUSIONS

TIF reduced the number of postprandial TLESRs, the number of TLESRs associated with reflux and EGJ distensibility. This resulted in a reduction of the number and proximal extent of reflux episodes and improvement of acid exposure in the upright position. The anti-reflux effect of TIF showed to be selective for liquid-containing reflux only, thereby preserving the ability of venting gastric air.

Intragastric balloon fundal or antral position affects weight loss and tolerability

BACKGROUND

Intragastric balloons (BIB) are routinely used for weight reduction. They should be placed to the gastric fundus, as this place is believed more effective for achievement of satiety and thus weight reduction. The aim of the present study was to evaluate whether the balloon position may affect 6-month weight loss as well as first-month side-effects, i.e. nausea, vomiting, and gastroesophageal reflux.

METHODS

From a total of 158 BIB-treated obese individuals, 105 females were found eligible, since the balloon in the stomach was found upon removal in the same position (fundus or antrum) placed at the time of insertion. These subjects were divided into fundus and antral groups. Data related to obesity were recorded on day 0 and upon BIB removal, 6 months thereafter. Data related to transient side-effects (nausea, vomiting, gastroesophageal reflux) were recorded on days 0-3, 7, and weekly thereafter, for 1 month.

RESULTS

BIB placed in the antrum was found to have significantly better results on weight loss parameters, while nausea, vomiting (p = 0.02) as well as gastroesophageal reflux still remained up to the fourth week in a relation to the fundus group. Similarly, the rate of gastric distension was found significantly increased (p = 0.001) during the days 1-3 in fundus group in relation to antrum, followed by a progressive decrease in both groups.

CONCLUSIONS

Intragastric balloon placed in the antrum lead to better results in weight reduction but to longer duration of tolerability-related side-effects, i.e., nausea, vomiting, and gastroesophageal reflux.