The effect of age on the key parameters in the Chicago classification: a study using high-resolution esophageal manometry in asymptomatic normal individuals

Esophageal motor disorders across ages: A retrospective multicentric analysis

BACKGROUND

Age-related changes in the gastrointestinal system are common and may be influenced by physiological aging processes. To date, a comprehensive analysis of esophageal motor disorders in patients belonging to various age groups has not been adequately reported.

METHODS

We conducted a retrospective assessment of high-resolution manometry (HRM) studies in a multicenter setting. HRM parameters were evaluated according to the Chicago Classification version 4.0. Epidemiological, demographic, clinical data, and main manometric parameters, were collected at the time of the examination. Age groups were categorized as early adulthood (<35 years), early middle-age (35-49 years), late middle-age (50-64 years), and late adulthood (≥65 years).

RESULTS

Overall, 1341 patients (632, 47.0% male) were included with a median age of 55 years. Late adulthood patients reported more frequently dysphagia (35.2%) than early adulthood patients (24.0%, p = 0.035), early middle-age patients (21.0%, p < 0.0001), and late middle-aged patients (22.7%, p < 0.0001). Esophagogastric junction outflow obstruction was more prevalent in late adulthood (16.7%) than in early adulthood (6.1%, p = 0.003), and in early middle-age (8.1%, p = 0.001). Patients with normal esophageal motility were significantly younger (52.0 years) than patients with hypercontractile esophagus (61.5 years), type III achalasia (59.6 years), esophagogastric junction outflow obstruction (59.4 years), absent contractility (57.2 years), and distal esophageal spasm (57.0 years), in multivariate model (p < 0.0001).

CONCLUSION

The rate of esophageal motor disorders is higher in older patients, in particular esophagogastric junction outflow obstruction and hypercontractile esophagus. Future prospective studies are necessary to confirm our results and to find tailored strategies to improve clinical outcomes.

Age Affects Esophageal Secondary Peristalsis More Than Primary as Assessed by FLIP Panometry and High-resolution Manometry

Age-related changes in esophageal function involve increased rates of dysmotility with advancing age (sometimes described as presbyesophagus).1-4 Specifically, advanced age has been associated with increased lower esophageal sphincter (LES) pressure and decreased peristaltic vigor.1-4 However, the mechanisms underlying these changes, including the relative relationship of primary peristalsis and secondary peristalsis over the lifespan, remain incompletely understood. Current approaches assess primary peristalsis using high-resolution manometry (HRM), with esophageal motility disorders defined using the Chicago Classification version 4.0 (CCv4.0), and secondary peristalsis using functional lumen imaging probe (FLIP) panometry.5,6 Although HRM and FLIP panometry motility diagnoses are often analogous, they can sometimes differ. For example, abnormal secondary peristalsis can occur when primary peristalsis is normal, which has been associated with reflux and non-obstructive dysphagia.7,8 This study aimed to examine the effect of age on primary peristalsis and secondary peristalsis.

High-resolution impedance manometry for comparing bolus transit between patients with non-obstructive dysphagia and asymptomatic controls

BACKGROUND

Currently, there are no high-resolution impedance manometry (HRIM)-based diagnostic criteria for non-obstructive dysphagia (NOD). New impedance parameters, such as the esophageal impedance integral (EII) and volume of inverted impedance (VII) ratios, have shown strong correlations with bolus transit. This study compared the EII and VII ratios as diagnostic tools for NOD.

METHODS

We analyzed 36 participants (12 patients with achalasia, 12 patients with NOD [7 with normal motility and 5 with ineffective esophageal motility], and 12 asymptomatic controls) who underwent HRIM with a maximum of 5 swallows per participant. The EII and VII ratios were calculated as Z2 (post-swallow)/Z1 (pre-swallow). Bolus transit was retrospectively evaluated using transluminal impedance analysis.

KEY RESULTS

Both EII and VII ratios could effectively distinguish the achalasia group from the non-achalasia groups (area under the receiver operating characteristic curve [AUROC]: 0.83 for VII vs. 0.80 for EII; p = 0.73). However, the VII ratio was significantly better in discriminating asymptomatic controls from patients with dysphagia (NOD + achalasia) (AUROC: 0.81 vs. 0.68; p = 0.01). Moreover, the VII ratio was better in discriminating asymptomatic controls from patients with NOD (AUROC: 0.68 vs. 0.51; p = 0.06). In repeated swallows, the VII ratio was consistently the lowest in controls and the highest in patients with achalasia, whereas the EII ratio did not show a consistent pattern.

CONCLUSIONS & INFERENCES

The VII ratio was more reliable than the EII ratio for describing bolus transit and distinguishing patients with NOD from asymptomatic controls, even during repeated measures of subsequent swallows.

The Predictive Value of Intraoperative Esophageal Functional Luminal Imaging Probe Panometry in Patients With Achalasia Undergoing Peroral Endoscopic Myotomy: A Single-center Experience

Background/Aims

We evaluated the clinical significance and prognostic power of functional luminal imaging probe (FLIP) panometry in patients with achalasia treated with peroral endoscopic myotomy (POEM), and examined the clinical parameters associated with symptomatic improvement and the presence of contractility (POC) following POEM.

Methods

We reviewed the electronic medical records of patients with achalasia treated with FLIP panometry and POEM at a tertiary teaching hospital in Seoul, Republic of Korea. Follow-up examination was composed of esophageal manometry and questionnaires on symptoms. We analyzed the FLIP data by interpolating using the cubic spline method in MATLAB.

Results

We retrospectively analyzed 33 men and 35 women (mean age 52 ± 17 years), of whom 14, 39, and 15 patients were diagnosed with achalasia types I, II, and III, respectively. The FLIP panometry diagnoses were reduced esophagogastric junction opening (REO) with a retrograde contractile response (n = 43); REO with an absent contractile response (n = 5); REO with a normal contractile response (n = 11); and a retrograde contractile response (n = 9). Overall, the patients showed improvements in Eckardt scores following POEM from 6.48 ± 2.20 to 1.16 ± 1.15 (P < 0.01). Post-POEM symptomatic improvement was not significantly associated with any of the clinical parameters, including panometry diagnosis. Conversely, post-POEM POC was significantly associated with the presence of repetitive antegrade contractions and achalasia subtypes (both P < 0.01).

Conclusion

While FLIP panometry was not significantly associated with the clinical course of achalasia, FLIP panometry was associated with POC following POEM and may complement manometry in the functional evaluation of esophageal motility disorders.

Effects of Age on Esophageal Motility: A High-Resolution Manometry Study

Background

Studies have found possible physiologic changes to esophageal motility with aging currently not taken into account in routine high-resolution manometry (HRM) interpretation. We aimed to quantify the relationship between these physiologic changes and aging to improve HRM interpretation.

Methods

We conducted a retrospective analysis of patients who underwent HRM at a tertiary hospital center between 2015 and 2019. Inclusion criteria were patients aged ≥18 years with normal HRM. Exclusion criteria were abnormal HRM, abnormal upper digestive endoscopy or imagery. Outcomes were median integrated relaxation pressure (IRP), lower esophageal sphincter (LES) pressure, distal contractal integral (DCI), distal latency (DL), and peristaltic break (PB) according to the v4.0 Chicago classification criteria. Effect of age was examined through univariate and multivariate linear regression analysis.

Results

We identified 1,917 patients with HRM and included 722 patients with normal exams (median age 56 years (interquartile range (IQR) 46 - 66), 63.8% female). Indications for HRM included dysphagia (39.6%), gastroesophageal reflux disease (29.5%), and chest pain (11.5%). There was statistically significant relationship between age and IRP (r = 0.20, P < 0.0001) as well as DCI (r = 0.12, P = 0.001) and DL (r = -0.09, P = 0.02). No statistically significant relationship was found between age and LES pressure or PB.

Conclusion

We found that IRP, DCI, and to a lesser extent, DL, are significantly correlated with the normal aging process in symptomatic patients. These findings should be taken into consideration when interpreting esophageal HRM.

The effects of different postures and provocative swallow materials on the normative Chicago 3.0 metrics in a healthy Asian population

BACKGROUND AND AIM

Variations in the Chicago 3.0 normative metrics may exist with different postures and with different provocative swallow materials in a healthy Asian population.

METHOD

Eligible healthy Malay volunteers were invited to undergo the high-resolution esophageal manometry (inSIGHT Ultima, Diversatek Healthcare, Milwaukee, WI, USA). In recumbent and standing positions, test swallows were performed using liquid, viscous, and solid materials. Metrics including integrated relaxation pressure 4 s (IRP-4 s, mmHg), distal contractile integral (DCI, mmHg s cm), distal latency (DL, s), and peristaltic break (PB, cm) were reported in median and 95th percentile.

RESULTS

Fifty of 57 screened participants were recruited, and 586 saline, 265 viscous, and 261 solid swallows were analyzed. Per-patient wise, in the recumbent position, 95th percentile for IRP-4 s, DCI, DL, and PB were 16.5 mmHg, 2431 mmHg s cm, 8.5 s, and 7.2 cm, respectively. We observed that with each posture, the use of viscous swallows led to changes in DL, but the use of solid swallows led to more changes in the metrics including DCI and length of PB. Compared with a recumbent posture, anupright posture led to lower IRP-4 s and DCI values. Both per-patient analysis and per-swallow analyses yielded almost similar results when comparing the different postures and types of swallows. No major motility disorders were observed in this cohort of asymptomatic population. However, more motility disorders were reported in the upright position.

CONCLUSIONS

Variations in metrics can be observed in different postures and with different provocative swallow materials in a healthy population. The normative Chicago 3.0 metrics are also determined for the Malay population.

[Diagnosis of Dysphagia: High Resolution Manometry & EndoFLIP]

Esophageal motility disorders were re-defined when high-resolution manometry was employed to better understand their pathogenesis. Newly developed parameters including integrated relaxation pressure (IRP), distal contractile integral, and distal latency showed better diagnostic yield compared with previously used conventional parameters. Therefore, Chicago classification was formulated, and its diagnostic cascade begins by assessing the IRP value. However, IRP showed limitation due to its inconsistency, and other studies have tried to overcome this. Recent studies showed that provocative tests, supplementing the conventional esophageal manometry protocol, have improved the diagnostic yield of the esophageal motility disorders. Therefore, position change from supine to upright, solid or semi-solid swallowing, multiple rapid swallows, and the rapid drink challenge were newly added to the manometry protocol in the revised Chicago classification version 4.0. Impedance planimetry enables measurement of bag cross-sectional area at various locations. The functional lumen imaging probe (FLIP) has been applied to assess luminal distensibility. This probe can also measure pressure, serial cross-sectional areas, and tension-strain relationship. The esophagogastric junction's distensibility is decreased in achalasia. Therefore, EndoFLIP can be used to assess contractility and distensibility of the esophagus in the patients with achalasia, including repetitive antegrade or retrograde contractions. EndoFLIP can detect achalasia patients with relatively low IRP, which was difficult to diagnose using the current high-resolution manometry. EndoFLIP also provides information on the contractile activity and distensibility of the esophageal body in patients with achalasia. The use of provocative tests, newly added in Chicago classification 4.0 version, and EndoFLIP can expand understanding of esophageal motility disorders.

Effects of the preoperative IRP values on the pathophysiology of patients with esophageal achalasia and on the treatment outcome of laparoscopic Heller-Dor surgery

PURPOSE

One diagnostic criterion of esophageal achalasia is that the integrated relaxation pressure (IRP) measured by high-resolution manometry (HRM) is at least 15 mmHg. Moreover, while the standard surgical treatment for esophageal achalasia is laparoscopic Heller-Dor surgery (LHD), there have been insufficient investigations concerning the surgical outcomes from the perspective of the preoperative IRP value.

METHODS

We split 121 cases in which LHD was performed as an initial treatment on patients with esophageal achalasia, into two categories according to the IRP median value, and performed a comparative investigation of the surgical outcomes with regard to the preoperative pathophysiology and symptoms.

RESULTS

The IRP median value was 29.6 mmHg. The high IRP group consisted of younger individuals and low BMI (p = 0.004 and p = 0.0273, respectively), and the percentage of Chicago classification Type II and III was high (p = 0.029) and the regurgitation score in the preoperative symptoms was high (p = 0.0043). However, no differences in the surgical outcomes were confirmed.

CONCLUSION

In patients with esophageal achalasia, the degree of the preoperative IRP value affects the age, BMI, preoperative LESP, and preoperative regurgitation symptoms. However, there were no effects on the surgical outcomes, with the surgical outcomes being satisfactory, regardless of the IRP value.

Normative reference values for esophageal high-resolution manometry in healthy adults: A systematic review

Establishing normative values of high-resolution esophageal manometry is necessary for accurate interpretation and comparison of measurements. In this systematic review, we aimed to summarize normal values for different esophageal high-resolution manometry systems. Moreover, we assessed the effect of body position, bolus consistency, and provocative maneuvers on these normative thresholds. We searched Medline, Embase, and the Cochrane Library from January 1st, 2006, to January 20th, 2020, for studies that reported normative data of high-resolution manometry in healthy volunteers. We assessed methodological quality of the included studies and planned a descriptive analysis. We analyzed data from 54 articles describing normative thresholds in high-resolution manometry using solid-state or water-perfused systems. Forty-six studies performed the manometry study in the supine position with liquid swallows, whereas sixteen studies described normative values in the upright position. Twelve studies assessed normative values for different bolus consistencies, and nine studies evaluated different provocative maneuvers. There is a considerable variety of normative values for esophageal high-resolution manometry depending on the equipment used and the protocols performed to obtain measurements. This should be taken into account when evaluating measurements in clinical practice and when comparing results of published research studies.

Effect of Body Position on High-resolution Esophageal Manometry Variables and Final Manometric Diagnosis

Background/Aims

According to the Chicago classification version 3.0, high-resolution manometry (HRM) should be performed in the supine position. However, with the patient in the upright/sitting position, the test could more closely simulate real-life behavior and may be better tolerated. We performed a systematic review of the literature to search whether the manometric variables and the final diagnosis are affected by positional changes.

Methods

A literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies published in English that compared HRM results in different body positions were included. Moreover, the change in diagnosis of esophageal motility disorders according to the shift of body position was investigated.

Results

Seventeen studies including 1714 patients and healthy volunteers met the inclusion criteria. Six studies showed a significant increase in lower esophageal sphincter basal pressure in the supine position. Integrated relaxation pressure was significantly higher in the supine position in 10 of 13 studies. Distal contractile index was higher in the supine position in 9 out of 10 studies. One hundred and fifty-one patients (16.4%) out of 922 with normal HRM in the supine position were diagnosed with ineffective esophageal motility (IEM) when the test was performed in the upright position (P < 0.001).

Conclusions

Performing HRM in the upright position affects some variables and may change the final manometric diagnosis. Further studies to determine the normal values in the sitting position are needed.

Minor esophageal functional disorders: are they relevant?

PURPOSE OF REVIEW

High resolution esophageal manometry (HRM) has expanded understanding of esophageal motor function. The Chicago Classification scheme has allowed systematic categorization of the myriad of manometric parameters identified during HRM. Multichannel intraluminal impedance pH has enhanced ambulatory reflux monitoring through complete assessment of esophageal content transit. However, the clinical implications of identified minor esophageal functional disorders remain unclear.

RECENT FINDINGS

Esophagogastric junction outlet obstruction is defined by esophagogastric junction obstruction with preserved peristalsis and may be managed expectantly, or in a manner similar to achalasia. Hypercontractile esophagus has been associated with dysphagia and non-cardiac chest pain, but the clinical significance is unclear as a majority of patients will improve without specific therapy. Additionally, these findings may be confounded by chronic opiate use. Ineffective esophageal motility is characterized by diminished esophageal contraction amplitude, potentially causing dysphagia and GERD. However, this is commonly identified in asymptomatic volunteers and may represent a normal variant. The multiple rapid swallow sequence can assess esophageal contraction reserve, which may predict post fundoplication dysphagia. The post-swallow induced peristaltic wave can serve as a surrogate of gastric refluxate clearance, providing important prognostic value. However, the associated time burden and lack of alternative therapeutic options limit its clinical utility.

SUMMARY

Minor esophageal functional disorders provide new therapeutic targets for symptomatic patients. However, these findings have inconsistent associations with symptoms and poorly defined therapeutic options. Minor esophageal function disorders should not be interpreted in isolation, with management decisions accounting for clinical, endoscopic, and radiographic factors in addition.

Elicitation of the Swallowing Reflex by Esophageal Stimulation in Healthy Subjects: An Evaluation Using High-Resolution Manometry

The purposes of this human study using high-resolution manometry were to verify whether the swallowing reflex can be evoked by intra-esophageal fluid injection and whether the reflex latency and manometric variables differ depending on the injected location, amount, or speed. Ten healthy individuals participated in this study. The tip of the intranasal catheter for injection was placed at 5 cm (upper), 10 cm (upper-middle), 15 cm (lower-middle), or 20 cm (lower) from the distal end of the upper esophageal sphincter (UES). An intra-esophageal injection of 3 mL or 10 mL of thickened water was administered and controlled at 3 mL/s or 10 mL/s. Latencies from the start of the injection to the onset of UES relaxation were compared regarding injection locations, amounts, and rates. Manometric variables of intra-esophageal injection and voluntary swallowing were compared. The latency became shorter when the upper region was injected. Latency after the 10-mL injection was shorter than that after the 3-mL injection (p < 0.01) when faster injection (10 mL/s) was used. Faster injection induced shorter latency (p < 0.01) when a larger volume (10 mL) was injected. Pre-maximum and post-maximum UES pressures during voluntary swallowing or during spontaneous swallowing when injecting the upper esophageal region were significantly higher than spontaneous swallowing at other regions (p < 0.01). Intra-esophageal fluid injection induces the swallowing reflex in humans. The most effective condition for inducing the swallowing reflex involved a larger fluid amount with a faster injection rate in the upper esophagus.

Normative values and factors affecting water-perfused esophageal high-resolution impedance manometry for a Chinese population

BACKGROUND

Combined esophageal high-resolution impedance manometry (HRIM) measures multiple pressures and bolus transit simultaneously, facilitating detailed assessment of esophageal motility. Currently, normative values for water-perfused HRIM systems for Chinese populations are lacking.

METHODS

Healthy volunteers were enrolled for comprehensive anthropometric measures, blood biochemistry tests, and an HRIM study using 22 water-perfused pressure sensors and 12 impedance channels. Ten 5-mL liquid swallows of saline at 30-second intervals were conducted. The following parameters were calculated: distal contractile integral (DCI), distal latency (DL), lower esophageal sphincter (LES) basal pressure, 4-second integrated relaxation pressure (IRP-4s), and complete bolus transit percentage. Normal values were established based on the 5th and 95th percentiles.

KEY RESULTS

All 66 participants (34 male, 32 female, aged 21-64 years) completed the study and tolerated the HRIM procedure well. The upper normal limit (95th percentile) of IRP-4 second was 20 mmHg. The 5th-95th percentile range for DCI, DL, and complete bolus transit was 99-2186 mmHg●s●cm, 6.2-11.3 second, and 50%-100%, respectively. Age was negatively correlated with DL. Females had significantly higher upper limits for IRP-4s and median DCI than males. Multivariate analyses confirmed that IRP-4s was higher in females, and that higher body mass index and waist circumference were associated with reduced DL and better bolus transit, respectively.

CONCLUSIONS AND INFERENCES

We established normative values for the water-perfused HRIM system for a Chinese population. Gender and anthropometric factors may affect various major HRIM parameters and should be taken into account when interpreting HRIM results in clinical practice.

Variation in esophageal physiology testing in clinical practice: Results from an international survey

BACKGROUND

Advances in clinical measurement of esophageal motility and function have improved the assessment of swallowing disorders and reflux symptoms. Variation in data acquisition, analysis, and reporting exists and impacts on diagnosis and management.

AIMS AND METHODS

This study examined variation in esophageal manometry methodology between institutions to establish the status in current practice. A structured survey was distributed through international NGM societies using an Internet-based platform. Questions explored infrastructure, technology, analysis, and reporting.

KEY RESULTS

Responses were received from 91 centers from 29 countries. Eighteen (20%) centers used "conventional" manometry, 75 (82%) high-resolution manometry, and 53 (58%) HR impedance manometry. All centers documented motility for single water swallows. The Chicago Classification was applied by 65 (71.4%) centers. In contrast, analysis of EGJ morphology varied widely. Adjunctive testing was often applied: multiple rapid swallows (77%), rapid drink challenge (77%), single solid swallows (63%), and a standard test meal (18%). Of 86 (94.5%) units that offered pH impedance (pH-Z) studies, approximately half (53.5%) performed tests on acid-suppressant medication in patients with a high pretest probability (eg, erosive esophagitis). Most (75.6%) centers manually reviewed every reflux event. Others examined pH-Z data only prior to symptoms. To assess symptom association with reflux events, 73.6% centers analyzed each symptom separately, whereas 29.7% centers pooled symptoms.

CONCLUSIONS AND INFERENCES

There is marked variation in the data acquisition, analysis, and reporting of esophageal manometry studies. Further efforts to improve quality and uniformity in testing and reporting are required. This survey provides information upon which best-practice guidelines can be developed.

Age-related impairment of esophagogastric junction relaxation and bolus flow time

AIM

To investigate the functional effects of abnormal esophagogastric (EGJ) measurements in asymptomatic healthy volunteers over eighty years of age.

METHODS

Data from 30 young controls (11 M, mean age 37 ± 11 years) and 15 aged subjects (9 M, 85 ± 4 years) were compared for novel metrics of EGJ-function: EGJ-contractile integral (EGJ-CI), “total” EGJ-CI and bolus flow time (BFT). Data were acquired using a 3.2 mm, 25 pressure (1 cm spacing) and 12 impedance segment (2 cm) solid-state catheter (Unisensor and MMS Solar GI system) across the EGJ. Five swallows each of 5 mL liquid (L) and viscous (V) bolus were analyzed. Mean values were compared using Student’s t test for normally distributed data or Mann Whitney U-test when non-normally distributed. A P value < 0.05 was considered significant.

RESULTS

EGJ-CI at rest was similar for older subjects compared to controls. “Total” EGJ-CI, measured during liquid swallowing, was increased in older individuals when compared to young controls (O 39 ± 7 mmHg.cm vs C 18 ± 3 mmHg.cm; P = 0.006). For both liquid and viscous bolus consistencies, IRP4 was increased (L: 11.9 ± 2.3 mmHg vs 5.9 ± 1.0 mmHg, P = 0.019 and V: 14.3 ± 2.4 mmHg vs 7.3 ± 0.8 mmHg; P = 0.02) and BFT was reduced (L: 1.7 ± 0.3 s vs 3.8 ± 0.2 s and V: 1.9 ± 0.3 s vs 3.8 ± 0.2 s; P < 0.001 for both) in older subjects, when compared to young. A matrix of bolus flow and presence above the EGJ indicated reductions in bolus flow at the EGJ occurred due to both impaired bolus transport through the esophageal body (i.e., the bolus never reached the EGJ) and increased flow resistance at the EGJ (i.e., the bolus retained just above the EGJ).

CONCLUSION

Bolus flow through the EGJ is reduced in asymptomatic older individuals. Both ineffective esophageal bolus transport and increased EGJ resistance contribute to impaired bolus flow.

ESOPHAGEAL MOTILITY IN MEN AND WOMEN EVALUATED BY HIGH-RESOLUTION MANOMETRY

BACKGROUND

Esophageal motility has been described in the literature as having differences between men and women. Most of these investigations use the water perfusion method for esophageal manometry. In this investigation the esophageal motility of men and women was compared with high-resolution manometry of the esophagus.

OBJECTIVE

To compare the esophageal motility of men and women with the high-resolution manometry method for esophageal manometry, performed in the sitting position. The hypothesis was that men and women have differences in esophageal motility.

METHODS

High-resolution manometry was performed in normal volunteers, 10 men [mean age: 37.5 (8.1) years] and 12 women [mean age: 38.7 (7.5) years], in the sitting position and with 10 swallows of a 5 mL bolus of saline, with an interval of at least 30 seconds between consecutive swallows. We evaluated the integrated relaxation pressure of the lower esophageal sphincter, contraction front velocity, distal contraction integral, distal latency, proximal contraction extension, proximal contraction duration >30 mmHg, proximal contraction duration, proximal contraction integral and maximal upper esophageal sphincter pressure.

RESULTS

There was no significant difference between men and women in the variables measured.

CONCLUSION

There was no difference in esophageal motility of men and women evaluated by the high resolution manometry method, in the sitting position with swallows of a liquid bolus.

High-resolution manometric evaluation of the effects of cisapride on the esophagus during administration of solid and liquid boluses in awake healthy dogs

OBJECTIVE To validate the use of high-resolution manometry (HRM) in awake, healthy dogs and compare the effects of bolus type (liquid vs solid) and drug treatment (saline [0.9% NaCl] solution [SS] vs cisapride) on esophageal pressure profiles. ANIMALS 8 healthy dogs. PROCEDURES In a crossover study, each dog received SS (10 mL) IV, and HRM was performed during oral administration of 10 boluses (5 mL each) of water or 10 boluses (5 g each) of canned food. Cisapride (1 mg/kg in 60 mL of SS) was subsequently administered IV to 7 dogs; HRM and bolus administration procedures were repeated. Two to 4 weeks later, HRM was repeated following administration of SS and water and food boluses in 4 dogs. Pressure profile data were obtained for all swallows, and 11 outcome variables were statistically analyzed. RESULTS After SS administration, predicted means for the esophageal contractile integral were 850.4 cm/mm Hg/s for food boluses and 660.3 cm/mm Hg/s for water boluses. Predicted means for esophageal contraction front velocity were 6.2 cm/s for water boluses and 5.6 cm/s for food boluses after SS administration. Predicted means for residual LES pressure were significantly higher following cisapride administration. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that HRM was feasible and repeatable in awake healthy dogs of various breeds and sizes. Stronger esophageal contractions and faster esophageal contraction velocity occurred during solid bolus and liquid bolus swallows, respectively. Lower esophageal sphincter pressure increased significantly following cisapride administration. Esophageal contractions and bolus transit latency should be further evaluated by HRM in clinically dysphagic dogs.

The Impact of Heller Myotomy on Integrated Relaxation Pressure in Esophageal Achalasia

BACKGROUND

A new high-resolution manometry (HRM) parameter, the integrated relaxation pressure (IRP), has been proposed for the assessment of esophageal-gastric junction (EGJ) relaxation. Our aim was to assess the effect of Heller myotomy on IRP in achalasia patients.

METHODS

We prospectively collected data on achalasia patients who underwent HRM between 2009-2014. Barium swallow was used to assess esophageal diameter and shape. Manometric diagnoses were performed by using the Chicago Classification v3. All patients with a confirmed diagnosis of achalasia were treated surgically with Heller Myotomy

RESULTS

One hundred thirty-nine consecutive achalasia patients (M:F = 72:67) represented the study population. All the patients had 100% simultaneous waves but 11 had an IRP < 15 mmHg. At median follow-up of 28 months, the median of IRP was significantly lower after surgery (27.4 [IQR 20.4-35] vs 7.1 [IQR 4.4-9.8]; p < 0.001), and so were the lower esophageal sphincter (LES) resting pressure (27 [IQR 18-33] vs 6 [IQR 3-11]; p < 0.001). At univariate analysis, IRP correlated with the gender, LES resting residual pressure, and dysphagia score.

CONCLUSIONS

This is the first study to have examined the role of IRP in achalasia, and how it changes after surgical treatment. An increased preoperative IRP correlated directly with a more severe dysphagia. The IRP was restored to normal by Heller myotomy.

Predictive value of routine esophageal high-resolution manometry for gastro-esophageal reflux disease

BACKGROUND

Using conventional manometry, gastro-esophageal reflux disease (GERD) was associated with a reduced lower esophageal sphincter (LES) pressure and impaired peristalsis. However, with a large overlap between GERD patients and controls, these findings are of limited clinical relevance. It is uncertain whether the more detailed information of high-resolution manometry (HRM) can discriminate GERD patients. Therefore, we aimed to determine to which extent HRM findings can predict GERD.

METHODS

HRM measurements in 69 patients with GERD and 40 healthy subjects were compared and the predictive value of HRM for the diagnosis of GERD was explored.

KEY RESULTS

GERD patients had a significantly lower contraction amplitude (55 vs 64 mmHg; p = 0.045) and basal LES pressure (10 vs 13.2 mmHg; p = 0.034) than healthy controls. GERD patients more often had a hiatal hernia than healthy subjects (30% vs 7%; p = 0.005). Patients with reflux esophagitis had a lower DCI than patients without reflux esophagitis (558 vs 782 mmHg cm s; p = 0.045). No significant difference was seen in contractile front velocity, distal latency, number of peristaltic breaks, residual LES pressure and LES length. On multivariate logistic regression analysis, both esophagogastric junction type I (OR 4.971; 95% CI 1.33-18.59; p = 0.017) and mean wave amplitude (OR 0.95; 95% CI 0.90-0.98; p = 0.013) were found to be independent predictors of GERD. However, the sensitivity and specificity of these findings were low.

CONCLUSIONS & INFERENCES

Hiatal hernia, low contraction amplitude and LES pressure are associated with GERD, but do not predict the disease with sufficient accuracy. Routine esophageal HRM can therefore not be used to distinguish GERD patients from healthy subjects.