Distal Contractile Integral Values Research Articles

Factors affecting the treatment outcomes of laparoscopic fundoplication for erosive reflux esophagitis: findings of esophageal pathological function tests.

To identify the factors that affect laparoscopic fundoplication (LF) treatment efficacy in patients with erosive gastroesophageal reflux disease (e-GERD) esophagitis, based on the findings of multichannel intraluminal impedance pH (MII-pH) and high-resolution manometry (HRM). The subjects were 102 patients with e-GERD diagnosed by endoscopy, who underwent LF as the initial surgery. To analyze the findings of MII-pH and HRM, the patients were divided into two groups: a cured group (CR), comprised of patients whose esophagitis was cured postoperatively; and a recurrence group (RE), comprised of patients who suffered recurrent esophagitis. There were 96 patients in the CR group and 6 in the RE group. MII-pH indicated that the acid reflux time, the longest reflux time, and the number of refluxes longer than 5min, were significantly higher in the RE group than in the CR group (p = 0.0028, p = 0.0008, p = 0.012, respectively). The HRM indicated that only the distal contractile integral (DCI) was significantly lower in the RE group (p = 0.0109). The results of this study indicate that esophageal clearance may affect the treatment outcome of LF. Based on the findings of MII-pH, the longest reflux time and the number of refluxes longer than 5min were important factors influencing the therapeutic effect, whereas based on the HRM, the DCI value was most important.

High-Resolution Manometry Thresholds and Motor Patterns Among Asymptomatic Individuals

ObjectiveHigh-resolution manometry (HRM) is the current standard for characterization of esophageal body and esophagogastric junction (EGJ) function. We aimed to examine the prevalence of abnormal esophageal motor patterns in health, and to determine optimal thresholds for software metrics across HRM systems. DesignManometry studies from asymptomatic adults were solicited from motility centers worldwide, and were manually analyzed using integrated relaxation pressure (IRP), distal latency (DL), and distal contractile integral (DCI) in standardized fashion. Normative thresholds were assessed using fifth and/or 95th percentile values. Chicago Classification v3.0 criteria were applied to determine motor patterns across HRM systems, study positions (upright vs supine), ages, and genders. ResultsOf 469 unique HRM studies (median age 28.0, range 18–79 years). 74.6% had a normal HRM pattern; none had achalasia. Ineffective esophageal motility (IEM) was the most frequent motor pattern identified (15.1% overall), followed by EGJ outflow obstruction (5.3%). Proportions with IEM were lower using stringent criteria (10.0%), especially in supine studies (7.1%–8.5%). Other motor patterns were rare (0.2%–4.1% overall) and did not vary by age or gender. DL thresholds were close to current norms across HRM systems, while IRP thresholds varied by HRM system and study position. Both fifth and 95th percentile DCI values were lower than current thresholds, both in upright and supine positions. ConclusionsMotor abnormalities are infrequent in healthy individuals and consist mainly of IEM, proportions of which are lower when using stringent criteria in the supine position. Thresholds for HRM metrics vary by HRM system and study position.

Application of a novel straight leg raise test during high-resolution manometry can predict esophageal contractile reserve in patients with gastroesophageal reflux disease.

Increased intra-abdominal pressure from abdominal compression augments esophageal peristalsis during high-resolution manometry (HRM), and straight leg raise (SLR) while supine increases intra-abdominal pressure. We determined if water swallows performed during SLR can mimic contraction reserve seen with multiple rapid swallows (MRS). Consecutive patients evaluated for GERD symptoms completed validated GERD questionnaires, esophageal HRM, and upper endoscopy. Distal contractile integral (DCI) was analyzed during single water swallows (10×5mL), MRS (5×2mL), and during SLR (5x5mL). Peristaltic breaks were measured using software tools with a 20mmHg isobaric contour. Univariate correlational analyses were performed to compare esophageal motor patterns and DCI values during single water swallows, MRS, and SLR. Of 103 study patients (mean age: 46.7±12.3years, 56.3% female), 50 (48.5%) had ineffective esophageal motility (IEM). Contraction reserve was observed on MRS in 62% with IEM, and 35.8% with normal motility (p=0.008). DCI was significantly higher during SLR compared to mean single swallow DCI in both IEM and normal motility patients (p<0.001 for each comparison). In IEM patients, SLR significantly reduced swallows with peristaltic breaks (6.1±3.7 vs 3.6±3.6; p<0.001) and shortened the length of the largest break (4.8±3.4 vs 3.0±3.0cm; p<0.001). DCI response following MRS correlated with DCI with swallows during SLR, with a correlational coefficient (Pearson's r) of 0.70 (p<0.001). Swallowing against the resistance of increased intra-abdominal pressure from SLR improves esophageal body peristaltic performance and predicts esophageal body contraction reserve.

Subjective Symptoms in Patients with Eosinophilic Esophagitis Are Related to Esophageal Wall Thickness and Esophageal Body Pressure.

Endoscopic ultrasonography (EUS) and high-resolution manometry (HRM) can be used in the evaluation of eosinophilic esophagitis (EoE) for frequent symptoms such as dysphagia. However, the role of these examinations is not clear. The aim of this study was to objectively evaluate the subjective symptoms of EoE patients with EUS and HRM. Patients who had endoscopic findings indicative of EoE and matched the number of eosinophil infiltrates used as diagnostic criteria were recruited between September 2018 and August 2019. Evaluable subjects underwent EUS and HRM and completed the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. The esophageal wall thickness (evaluated with EUS) and HRM parameters between patients with and without symptoms were retrospectively compared. Symptomatic patients were re-examined using EUS and HRM 6months after treatment. A total of 35 patients (29 males, median age of 49years) were divided into symptomatic (20 patients) and asymptomatic groups (15 patients). The esophageal wall was thicker, and the distal contractile integral (DCI) values were higher in the symptomatic group (P < 0.001). In addition, DCI values were positively correlated with esophageal wall thickness. After treatment, the GSRS scores showed an improving trend for each item. Esophageal wall thickness and DCI values were significantly decreased (Ps < 0.001). Esophageal wall thickening and increased esophageal body pressure may be involved in subjective symptoms. In addition, treatment may reduce esophageal thickness and pressure along with improvement of subjective symptoms.

Sleeve gastrectomy and gastroesophageal reflux: a comprehensive endoscopic and pH-manometric prospective study.

The impact of sleeve gastrectomy (SG) on gastroesophageal reflux disease (GERD) is still greatly debated. Most of the current evidence available is solely based on symptom evaluation or medication use, while a minority have implemented objective functional measurements. To better comprehend the pathophysiological mechanisms involved in the genesis of GERD after SG. University Hospital, Italy. A total of 21 patients affected by morbid obesity and eligible for SG were prospectively enrolled in the present study. Patients were evaluated by means of endoscopy, high-resolution manometry (HRM), 24-hour pH monitoring, and the Gastroesophageal Reflux Disease Health-Related Quality of Life questionnaire. Follow-up was completed at least 1 year post operation (mean follow-up, 14.3 ± 2.1 mo) by 19 patients. Body mass index decreased from 41.2 ± .9 to 26.8 ± .8 kg/m2 (P < .001). Distal contractile integral significantly decreased from 2772.8 ± 399.9 mm Hg/s/cm to 2060.4 ± 338.9 mm Hg/s/cm (P = .01). The 24-hour pH monitoring showed an overall reduction tendency of acid reflux, although this was not statistically significant. All analyzed endoscopic findings withstood substantial pejorative modifications after SG (P < .01). Distal contractile integral values at baseline predicted postoperative Z-line upward migration; HRM, distal latency, and DeMeester score at baseline predicted the development of erosive esophagitis at follow-up, by bootstrap estimates of a logistic regression. Postoperative GERD-related esophageal sequelae should be carefully considered after SG. Our results demonstrate how acid reflux does not seem to play a relevant role in the pathophysiology of post-SG GERD. Baseline HRM can help stratify the risk of developing erosive esophagitisand Z-line upward migration after SG, while postoperative endoscopic surveillance should be encouraged regardless of the presence or absence of symptoms.

Differences in clinical characteristics between conservative-treatment-response group and refractory (surgical-treatment) group in patients with jackhammer esophagus.

Jackhammer esophagus (JE) is a rare disease with unclear clinical features. The objective of this study was to retrospectively compare the clinical characteristics of patients with JE whose symptoms were controlled with conservative treatment, such as observation or medication, versus those who were required surgical treatment, such as surgical myotomy or per oral endoscopic myotomy. Eighteen patients with JE were included in this study. The patients were divided into two groups: patients who responded to conservative treatment (C group) and patients who were refractory to conservative treatment and underwent surgery (S group). Patient age, sex, disease duration before treatment, symptoms, esophagogastroduodenoscopic (EGD) findings, esophagographic findings, esophageal wall thickness on computed tomography, number of swallows with hypercontractile peristalsis in 10 water swallows, and maximum distal contractile integral (DCI) were compared between the groups. Thirteen of 18 patients (72%) were in the C group and five of 18 (28%) were in the S group. There were no significant differences in age, sex, disease duration before treatment, symptoms, EGD findings, esophagographic findings, esophageal wall thickness, or number of swallows with hypercontractile peristalsis between the groups. On Starlet high-resolution manometry, the median maximum DCI value was significantly higher in the S group (32,651mmHg-s-cm) than in the C group (17,926mmHg-s-cm) (P = 0.0136). JE treatment should be carefully considered because some patients require surgery, whereas others are controlled with conservative treatment alone. A higher DCI value in patients with JE may predict resistance to conservative treatment.

Distal contractile integral measurement and vascular compression in the esophagus: a problem unsolved?

Distal contractile integral (DCI) is influenced by factors other than esophageal smooth muscle contractility, such as intrabolus pressure and vascular and respiratory movements' artifacts. We aimed to determine the size of the contribution of pressures generated by vascular compression on the esophagus to the DCI measured in HRM recordings in symptomatic patients. HRM manometry recordings obtained from 383 subjects referred to the GI motility laboratory at a tertiary center (2012-2016) were evaluated by visual inspection for evidence of strong vascular compression (SVC) of the esophagus. Clinical, demographic, manometric, and serologic data for Chagas disease were obtained. Subjects were classified, respectively, as asymptomatics (ASYM) or symptomatics (SYMP). DCI and SVC-DCI were measured, and the SVC-DCI/DCI ratio was expressed as a percentage and the difference between DCI and SVC-DCI (neat-DCI) was calculated. DCI, SVC-DCI, SVC-DCI/DCI % and neat-DCI from SYMP and ASYM were compared. SVC was conspicuous in 42 of 383 subjects (11%). In 33 subjects, SVC was detected only in supine position. SVC was localized in middle esophagus in 21 subjects (50%), in distal esophagus in 12 subjects (29%) and in both regions in 9 subjects (21%). In 9 subjects, SVC vanished from the swallowing window analysis (21%). SVC is a common finding in esophageal HRM study, particularly in the supine position. Occasionally, its contribution to DCI value is sufficiently great to masquerade esophageal hypocontractility. Different manometric protocols may be required in patients with SVC.

P173 HIGH-RESOLUTION MANOMETRIC FINDINGS AFTER MAGNETIC SPHINCTER AUGMENTATION

Abstract Aim The aim of this study was to evaluate esophageal motility before and after Magnetic Sphincter Augmentation (MSA) for medically refractory Gastro-Esophageal Reflux Disease (GERD). Background and Methods MSA (LINX® Reflux Management System) is intended for patients with chronic GERD with incomplete symptom relief from proton-pump inhibitors (PPI) and abnormal acid exposure. A prospectively collected database of patients who underwent MSA between 2007 and 2019 was queried. All patients who completed pre- and post-operative high-resolution manometry (HRM) were included in the study. Additional investigations included Health-Related Quality of Life (GERD-HRQL) questionnaire, Functional Outcome Swallowing Scale (FOSS), upper gastrointestinal endoscopy, barium swallow, and 24-96 hours pH-study. Data were analyzed using Wilcoxon signed rank test and McNemar test. Results Forty-five patients met the inclusion criteria. The median follow-up was 10 months (IQR 6). Compared to baseline, there was a statistically significant reduction in PPI use (p=0.000), rate of heartburn (p=0.000), regurgitation (p=0.008), and extra-esophageal symptoms (p=0.000). Only three (6.7%) patients required dietary changes. The GERD-HRQL score significantly improved (p=0.000). There was a significant increase in the Lower Esophageal Sphincter (LES) competency, including LES length (p=0.004) and Esophago-gastric Contractile Integral ((EGJ-CI) (p=0.000). A significant increase in integrated relaxation pressure (IRP) (p=0.000), mean Distal Contractile Integral (DCI) (p=0.008) and intrabolus pressure (p=0.000) was also found. Thirteen (28.9%) patients presented pre-operative Ineffective Esophageal Motility (IEM) and five of them resolved postoperatively. Two patients (4.4%) developed IEM after surgery: both had IRP and DCI values within normal limits, and one of them complained of dysphagia. However, the GERD-HRQL score recovered in both patients. Conclusion MSA was clinically effective in relieving both typical and atypical GERD symptoms. LES competency increased after MSA. EGJ outflow obstruction was uncommon and not associated with symptoms. Finally, ineffective esophageal motility may reverse to normal after MSA.

High-resolution manometry findings after Linx procedure for gastro-esophageal reflux disease.

Magnetic sphincter augmentation with the Linx® system is a novel laparoscopic procedure for the treatment of gastro-esophageal reflux disease (GERD). Only few data are available regarding the impact of Linx on high-resolution manometry (HRM) variables. The prospectively collected database of patients who underwent Linx procedure at a single institution was queried. All patients who completed pre- and postoperative HRM, GERD health-related quality of life (GERD-HRQL) questionnaire, and functional outcome swallowing scale (FOSS) questionnaire were included in the study. Forty-five out of 304 patients were included. At a median follow-up of 12months (IQR 10) after surgery, a statistically significant increase of lower esophageal sphincter (LES) total length (P=.002), intra-abdominal length (P=.001), integrated relaxation pressure (IRP), intrabolus pressure (IBP), and esophagogastric contractile integral (EGJ-CI) was noted (P<.001). Distal esophageal amplitude (P=.004), mean distal contractile integral (DCI) (P<.001), post multiple repeated swallows DCI (P=.001), and the percent of normal peristalsis increased (P=.040). All patients were relieved of reflux symptoms. Ineffective esophageal motility reversed to normal in 36% of patients after surgery. The only factor significantly associated with postoperative dysphagia was preoperative dysphagia (P=.006). Postoperatively, a significant correlation between IRP and DCI (r=0.361 and P=.019) and between IBP and DCI (r=0.443 and P=.003) was found. The Linx procedure had a remarkable effect on esophageal motility in the short-term follow-up. It appears that the overall postoperative increase of IRP and IBP may justify the higher DCI values. Preoperative dysphagia was the only factor associated with postoperative dysphagia.

Length Normalisation for Pharyngeal and Distal Contractile Integrals: Is It Necessary?

Introduction: High-resolution pharyngeal manometry (HRPM) is instrumental in evaluation of the intraluminal pressure in the pharynx, thus can be utilized in guiding therapy. The pharyngeal contractile integral (PhCI) is a HRPM metric assessing “vigor” of the pharyngeal contraction, and is analogous to the distal contractile integral (DCI) of the esophagus. Pharyngeal and esophageal length can vary from person to person and may confound PhCI and DCI measurements, so we decided to investigate this further. Methods: To compare normalized (nPhCI) and (nDCI) versus non-normalized PhCI and DCI using pharyngeal and esophageal length measurementsRetrospective study including 100 people underwent HRM excluding those with total absence of peristalsis. nDCI was calculated by dividing average DCI to their esophageal length which was defined by HRM as the distance between inferior border of UES to the upper of the LES. nPhCI was calculated by dividing average PhCI to its pharyngeal length. Pharyngeal length was measured radiographically from anterior superior edge of C1 vertebra to the anterior inferior edge of C5. Results: Results are summarized in table 1 and 2. nPhCI was tightly correlated with the original average PhCI, suggesting that pharyngeal length is fairly constant over the range of observed PhCI (r=0.95, p<0.001) (figure 1A). nDCI was also tightly correlated with the original average DCI value (r=0.99, p<0.001) (figure 1B). Conclusion: Data suggests that “normalization” for pharyngeal and esophageal lengths are not necessary when completing HRM. PhCI may a useful indicator of the severity of pharyngeal swallowing impairment. HRPM has the potential to be a valuable adjunct testing procedure in the evaluation and treatment of dysphagic individuals. 384_A Figure 1 No Caption available.384_B Figure 2 No Caption available.384_C Figure 3 No Caption available.

Role of Esophageal Motility, Acid Reflux, and of Acid Suppression in Nonobstructive Dysphagia.

The present study was aimed at evaluating, in dysphagic patients, the role of high-resolution manometry (HRM) findings, presence of gastroesophageal reflux disease (GERD), and proton-pump inhibitor (PPI) therapy on dysphagia perception. A relevant proportion of patients with nonobstructive dysphagia present normal esophageal HRM findings. Patients with GERD often complain of dysphagia and factors, such as hypersensitivity, might be involved in its occurrence. In total, 37 nonerosive reflux disease (NERD) patients with only dysphagia (group 1) and 52 patients with both dysphagia and typical GERD symptoms (group 2) were evaluated with symptom scores, HRM combined with impedance and 24 hours impedance-pH monitoring. In total, 44 NERD patients, not presenting dysphagia, underwent the same protocol. A total of 22/37 group 1 patients [11 with pathologic acid exposure time (AET)] were treated with esomeprazole 40 mg oid for 4 weeks and were reassessed during the last week of therapy. A total of 15/37 group 1 patients (40%), 27/52 group 2 patients (52%), and 19/44 (43%) NERD patients presented pathologic AET [P=not significant (NS)]. Group 1 patients with a pathologic AET showed a significantly lower mean distal contractile integral (DCI) and a significant correlation (ρ=-0.71) between individual DCI and total bolus transit time values. During PPI therapy, in group 1 patients with pathologic AET, the mean dysphagia score value decreased significantly [7.5 (range, 3 to 9) before, 4 (range, 2 to 6) during PPI; P<0.01)] and mean DCI value increased significantly. In total, 40% of dysphagic patients show a pathologic AET and reduced peristaltic vigor. In these patients, an adequate PPI therapy significantly decreases dysphagia frequency and severity and improves the esophageal peristaltic force.

Interobserver Variability in Esophageal Body Measurements With High-resolution Manometry Among New Physician Users

To evaluate interobserver variability among 4 new physician users on measures of esophageal body function. Esophageal high-resolution manometry allows observation of esophageal motility by pressure topography plots. Little is known about the interobserver variability among physicians. Two resident and 2 fellow level physicians each interpreted 10 liquid swallows of 20 esophageal high-resolution manometry studies (n = 200 swallows) using the BioVIEW Analysis Suite (Sandhill Scientific Inc.). Studies evaluated were from patients referred for evaluation of dysphagia but found to have normal esophageal manometry and complete liquid bolus transit. Physicians received an orientation session and reviewed recent literature. Each physician recorded contractile front velocity (CFV) and distal contractile integral (DCI) for each liquid swallow. Interobserver agreements for CFV and DCI were assessed by intraclass correlation (ICC) values. Linear correlations between measurements by 2 readers were assessed using linear regression modeling techniques. CFV and DCI values of up to 200 data points were analyzed. Four reader results for CFV and DCI showed strong agreement although stronger for DCI measures (ICC = 0.94; range, 0.91 to 0.98) in comparison with CFV (ICC = 0.79; range, 0.52 to 0.82). Further correlation was performed with 2 readers; readers 1 and 2 revealed excellent correlation for DCI (r = 0.95, P < 0.001) and good correlation for CFV (r = 0.61, P < 0.001). With a thorough orientation session, good to excellent agreement for CFV and DCI measurements can be obtained from new physician users. CFV measures exhibit greater interobserver variability possibly due to the artifact produced by intraesophageal pressurization.

High-Resolution Manometry Correlates of Ineffective Esophageal Motility

There are currently no criteria for ineffective esophageal motility (IEM) and ineffective swallow (IES) in esophageal pressure topography (EPT). Our aims were to use high-resolution manometry metrics to define IEM within the Chicago Classification and to determine the distal contractile integral (DCI) threshold for IES. The EPT of 150 patients with either dysphagia or reflux symptoms were reviewed. Peristaltic function in EPT was defined by the Chicago Classification; the corresponding conventional line tracing (CLT) were reviewed separately. Generalized linear mixed models were used to find thresholds for DCI corresponding to traditionally determined IES and failed swallows. An external validation sample was used to confirm these thresholds. In terms of swallow subtypes, IES in CLT were a mixture of normal, weak, and failed peristalsis in EPT. A DCI of 450 mm Hg-s-cm was determined to be optimal in predicting IES. In the validation sample, the threshold of 450 mm Hg-s-cm showed strong agreement with CLT determination of IES (positive percent agreement 83%, negative percent agreement 90%). The patient diagnostic level agreement between CLT and EPT was good (78.6% positive percent agreement and 63.9% negative percent agreement), with negative agreement increasing to 92.0% if proximal breaks were excluded. The manometric correlate of IEM in EPT is a mixture of failed swallows and weak swallows with breaks in the middle/distal troughs. A DCI value <450 mm Hg-s-cm can be used to predict IES previously defined in CLT. IEM can be defined by >5 swallows with weak/failed peristalsis or with a DCI <450 mm Hg-s-cm.

Su1087 Heartburn and Condition of Distal Part of Esophagus in Pregnancy

Ineffective esophageal motility (IEM) has been observed in erosive and non-erosive reflux disease (NERD) patients and may account for delayed bolus transit and impaired esophageal reflux clearance. It has been demonstrated that conventional manometry findings cannot predict reflux clearance in GERD patients. High resolution manometry (HRM) allows an accurate analysis of esophageal motility. Distal contractile integral (DCI) integrates the length, contractile vigour, and duration of contraction of the first two segments of the distal esophagus. Aim: To assess the correlation between HRM findings and reflux clearance in GERD patients. Methods: Following a 3-week washout from PPI and/or H2 antagonists, HRM and 24-hour ambulatory multichannel pH-impedance (pH-MII) monitoring were performed in 37 consecutive GERD patients, with no evidence of hiatal hernia at endoscopy. Patients were analyzed in the supine position, a catheter with 36 solid state pressure sensors located at 1 cm intervals (MMS, HRIM, Enschede, The Netherlands) was used. Data were stored and analyzed using dedicated software. A total of 10 saline (5 ml) swallows, at 30sec intervals were analyzed in each subject. The pH-impedance assembly was positioned with the pH electrode at 5cm above the LES and impedance measuring segments at 3, 5, 7, 9, 15 and 17cm above LES (Sandhill Scientific, USA). Reflux episodes were classified according to standardized criteria. Mean reflux clearance time (RCT) and reflux exposure time (RET) were calculated using Bioview software analysis, after a manual analisys of each pH-MII tracing. DCI was calculated and correlated to RCT and RET values by means of linear regression analysis. HRM tracings were analyzed according to the Chicago classification. IEM was defined by the presence of hypothensive or absent peristaltic waves in >20% of deglutitions. Results: Of the 37 patients, 30 showed normal esophageal motility and 7 IEM. Mean DCI values were 1562 (95% CI, 1203-1921) mmHg*s−1*cm−1 in all patients and 182 (95% CI, 122-242) mmHg*s−1*cm−1 in the 7 patients with IEM (p<0.001). Mean RCT and RET were 12.2 sec. and 3.6% of total recording time in all 37 patients, 13.5 sec. and 6.5% in the 7 IEM patients. No correlation was found between DCI and mean RCT and RET (r= 0.3 and 0.25, respectively). Weak correlation was found between DCI and mean RCT in the subgroup of IEM patients (r= 0.65, p<0.05). Conclusions: failure of esophageal motility seems to play a weak role in the clearing of gastroesophageal reflux episodes. DCI is not correlated to impaired esophageal reflux clearing whose occurrence could depend on the balance between the magnitude of the motility weakness and of the flow resistance at esophago-gastric junction.

P.19.3 ESOPHAGEAL HIGH RESOLUTION MANOMETRY FINDINGS DO NOT CORRELATE WITH CLEARANCE OF GASTRO-ESOPHAGEAL REFLUX IN GERD PATIENTS

Ineffective esophageal motility (IEM) has been observed in erosive and non-erosive reflux disease (NERD) patients and may account for delayed bolus transit and impaired esophageal reflux clearance. It has been demonstrated that conventional manometry findings cannot predict reflux clearance in GERD patients. High resolution manometry (HRM) allows an accurate analysis of esophageal motility. Distal contractile integral (DCI) integrates the length, contractile vigour, and duration of contraction of the first two segments of the distal esophagus. Aim: To assess the correlation between HRM findings and reflux clearance in GERD patients. Methods: Following a 3-week washout from PPI and/or H2 antagonists, HRM and 24-hour ambulatory multichannel pH-impedance (pH-MII) monitoring were performed in 37 consecutive GERD patients, with no evidence of hiatal hernia at endoscopy. Patients were analyzed in the supine position, a catheter with 36 solid state pressure sensors located at 1 cm intervals (MMS, HRIM, Enschede, The Netherlands) was used. Data were stored and analyzed using dedicated software. A total of 10 saline (5 ml) swallows, at 30sec intervals were analyzed in each subject. The pH-impedance assembly was positioned with the pH electrode at 5cm above the LES and impedance measuring segments at 3, 5, 7, 9, 15 and 17cm above LES (Sandhill Scientific, USA). Reflux episodes were classified according to standardized criteria. Mean reflux clearance time (RCT) and reflux exposure time (RET) were calculated using Bioview software analysis, after a manual analisys of each pH-MII tracing. DCI was calculated and correlated to RCT and RET values by means of linear regression analysis. HRM tracings were analyzed according to the Chicago classification. IEM was defined by the presence of hypothensive or absent peristaltic waves in >20% of deglutitions. Results: Of the 37 patients, 30 showed normal esophageal motility and 7 IEM. Mean DCI values were 1562 (95% CI, 1203-1921) mmHg*s−1*cm−1 in all patients and 182 (95% CI, 122-242) mmHg*s−1*cm−1 in the 7 patients with IEM (p<0.001). Mean RCT and RET were 12.2 sec. and 3.6% of total recording time in all 37 patients, 13.5 sec. and 6.5% in the 7 IEM patients. No correlation was found between DCI and mean RCT and RET (r= 0.3 and 0.25, respectively). Weak correlation was found between DCI and mean RCT in the subgroup of IEM patients (r= 0.65, p<0.05). Conclusions: failure of esophageal motility seems to play a weak role in the clearing of gastroesophageal reflux episodes. DCI is not correlated to impaired esophageal reflux clearing whose occurrence could depend on the balance between the magnitude of the motility weakness and of the flow resistance at esophago-gastric junction.

Automated calculation of the distal contractile integral in esophageal pressure topography with a region‐growing algorithm

The distal contractile integral (DCI) is an index of contractile vigor in high-resolution esophageal pressure topography (EPT) calculated as the product of amplitude, duration, and span of the distal esophageal contraction. The aim of this study was to develop an automated algorithm calculating DCI. The DCI was calculated conventionally using ManoView™ (Given Imaging, Los Angeles, CA, USA) software in EPT studies from 72 controls and 20 patients and compared to the calculation using a MATLAB™ (Version 7.9.0, R2009b; The MathWorks Inc., Natick, MA, USA) 'region-growing' algorithm. This algorithm first established the spatial limits of the distal contraction (the proximal pressure trough to either the distal pressure trough or to the superior margin of the lower esophageal sphincter at rest). Pixel-by-pixel horizontal line segments were then analyzed within this span starting at the pressure maximum and extending outward from that point. The limits of 'region-growing' were defined either by the spatial DCI limits or by encountering a pressure <20 mmHg. The DCI was then calculated as the total units of mmHg s cm greater than 20 mmHg within this domain. Excellent correlation existed between the two methods (r = 0.98, P < 0.001). The DCI values obtained with the conventional calculation were slightly but significantly greater than with the region-growing algorithm. Differences were attributed to the inclusion of vascular pressures in the conventional calculation or to differences in localization of the distal limit of the DCI. The proposed region-growing algorithm provides an automated method to calculate DCI that limits inclusion of vascular pressure artifacts and minimizes the need for user input in data analysis.

Phenotypes and Clinical Context of Hypercontractility in High-Resolution Esophageal Pressure Topography (EPT)

This study aimed to refine the criteria for esophageal hypercontractility in high-resolution esophageal pressure topography (EPT) and to examine the clinical context in which it occurs. A total of 72 control subjects were used to define the threshold for hypercontractility as a distal contractile integral (DCI) greater than observed in normals. In all, 2,000 consecutive EPT studies were reviewed to find patients exceeding this threshold. Concomitant EPT and clinical variables were explored. The greatest DCI value observed in any swallow among the control subjects was 7,732 mm Hg-s-cm; the threshold for hypercontractility was established as a swallow with DCI >8,000 mm Hg-s-cm. A total of 44 patients were identified with a median maximal DCI of 11,077 mm Hg-s-cm, all with normal contractile propagation and normal distal contractile latency, thereby excluding achalasia and distal esophageal spasm. Hypercontractility was associated with multipeaked contractions in 82% of instances, leading to the name "Jackhammer Esophagus." Dysphagia was the dominant symptom, although subsets of patients had hypercontractility in the context of esophagogastric junction (EGJ) outflow obstruction, reflux disease, or as an apparent primary motility disorder. We describe an extreme phenotype of hypercontractility characterized in EPT by the occurrence of at least a single contraction with DCI >8,000 mm Hg-s-cm, a value not encountered in control subjects. This phenomenon, branded "Jackhammer Esophagus," was usually accompanied by dysphagia and occurred both in association with other esophageal pathology (EGJ outflow obstruction, reflux disease) or as an isolated motility disturbance. Further studies are required to define the pathophysiology and treatment of this disorder.