Esophagogastric junction distensibility measurements during Heller myotomy and POEM for achalasia predict postoperative symptomatic outcomes.

BACKGROUND: The functional lumen imaging probe (FLIP) is a novel diagnostic tool that can be used to measure esophagogastric junction (EGJ) distensibility. In this study, we performed intraoperative FLIP measurements during laparoscopic Heller myotomy (LHM) and peroral esophageal myotomy (POEM) for treatment of achalasia and evaluated the relationship between EGJ distensibility and postoperative symptoms. METHODS: Distensibility index (DI) (defined as the minimum cross-sectional area at the EGJ divided by distensive pressure) was measured with FLIP at two time points during LHM and POEM: (1) at baseline after induction of anesthesia, and (2) after operation completion. RESULTS: Measurements were performed in 20 patients undergoing LHM and 36 undergoing POEM. Both operations resulted in an increase in DI, although this increase was larger with POEM (7 ± 3.1 vs. 5.1 ± 3.4 mm(2)/mmHg, p < .05). The two patients (both LHM) with the smallest increases in DI (1 and 1.6 mm(2)/mmHg) both had persistent symptoms postoperatively and, overall, LHM patients with larger increases in DI had lower postoperative Eckardt scores. In the POEM group, there was no correlation between change in DI and symptoms; however, all POEM patients experienced an increase in DI of >3 mm(2)/mmHg. When all patients were divided into thirds based on final DI, none in the lowest DI group (<6 mm(2)/mmHg) had symptoms suggestive of reflux (i.e., GerdQ score >7), as compared with 20 % in the middle third (6-9 mm(2)/mmHg) and 36 % in the highest third (>9 mm(2)/mmHg). Patients within an "ideal" final DI range (4.5-8.5 mm(2)/mmHg) had optimal symptomatic outcomes (i.e., Eckardt ≤ 1 and GerdQ ≤ 7) in 88 % of cases, compared with 47 % in those with a final DI above or below that range (p < .05). CONCLUSIONS: Intraoperative EGJ distensibility measurements with FLIP were predictive of postoperative symptomatic outcomes. These results provide initial evidence that FLIP has the potential to act as a useful calibration tool during operations for achalasia.

An extended proximal esophageal myotomy is necessary to normalize EGJ distensibility during Heller myotomy for achalasia, but not POEM.

BACKGROUND: For laparoscopic Heller myotomy (LHM), the optimal myotomy length proximal to the esophagogastric junction (EGJ) is unknown. In this study, we used a functional lumen imaging probe (FLIP) to measure EGJ distensibility changes resulting from variable proximal myotomy lengths during LHM and peroral esophageal myotomy (POEM). METHODS: Distensibility index (DI) (defined as the minimum cross-sectional area at the EGJ divided by pressure) was measured with FLIP after each operative step. During LHM and POEM, each patient's myotomy was performed in two stages: first, a myotomy ablating only the EGJ complex was created (EGJ-M), extending from 2 cm proximal to the EGJ, to 3 cm distal to it. Next, the myotomy was lengthened 4 cm further cephalad to create an extended proximal myotomy (EP-M). RESULTS: Measurements were performed in 12 patients undergoing LHM and 19 undergoing POEM. LHM resulted in an overall increase in DI (1.6 ± 1 vs. 6.3 ± 3.4 mm(2)/mmHg, p < 0.001). Creation of an EGJ-M resulted in a small increase (1.6-2.3 mm(2)/mmHg, p < 0.01) and extension to an EP-M resulted in a larger increase (2.3-4.9 mm(2)/mmHg, p < 0.001). This effect was consistent, with 11 (92%) patients experiencing a larger increase after EP-M than after EGJ-M. Fundoplication resulted in a decrease in DI and deinsufflation an increase. POEM resulted in an increase in DI (1.3 ± 1 vs. 9.2 ± 3.9 mm(2)/mmHg, p < 0.001). Both creation of the submucosal tunnel and performing an EGJ-M increased DI, whereas lengthening of the myotomy to an EP-M had no additional effect. POEM resulted in a larger overall increase from baseline than LHM (7.9 ± 3.5 vs. 4.7 ± 3.3 mm(2)/mmHg, p < 0.05). CONCLUSIONS: During LHM, an EP-M was necessary to normalize distensibility, whereas during POEM, a myotomy confined to the EGJ complex was sufficient. In this cohort, POEM resulted in a larger overall increase in EGJ distensibility.

Esophageal body adaptation to Nissen fundoplication: Increased esophagogastric outflow resistance yields delayed and sustained peristaltic contractions without increased amplitude.

BACKGROUND: Improvement in lower esophageal sphincter (LES) competency after laparoscopic Nissen fundoplication (LNF) is well established, yet esophageal body physiology data are limited. We aimed to describe the impact of LNF on whole esophagus physiology using standard and novel manometric characteristics. METHODS: A cohort of patients with an intact fundoplication without herniation and no postoperative dysphagia were selected and underwent esophageal manometry at one-year after surgery. Pre- and post-operative manometry files were reanalyzed using standard and novel manometric characteristics and compared. KEY RESULTS: A total of 95 patients were included in this study. At 16.1 (8.7) months LNF increased LES overall and abdominal length and resting pressure (p < 0.0001). Outflow resistance (IRP) increased [5.8 (3-11) to 11.1 (9-15), p < 0.0001] with a 95th percentile of 20 mmHg in this cohort of dysphagia-free patients. Distal contractile integral (DCI) also increased [1177.0 (667-2139) to 1321.1 (783-2895), p = 0.002], yet contractile amplitude was unchanged (p = 0.158). There were direct correlations between pre- and post-operative DCI [R: 0.727 (0.62-0.81), p < 0.0001] and postoperative DCI and postoperative IRP [R: 0.347 (0.16-0.51), p = 0.0006]. Contractile front velocity [3.5 (3-4) to 3.2 (3-4), p = 0.0013] was slower, while distal latency [6.7 (6-8) to 7.4 (7-9), p < 0.0001], the interval from swallow onset to proximal smooth muscle initiation [4.0 (4-5) to 4.4 (4-5), p = 0.0002], and the interval from swallow onset to point when the peristaltic wave meets the LES [9.4 (8-10) to 10.3 (9-12), p < 0.0001] were longer. Esophageal length [21.9 (19-24) to 23.2 (21-25), p < 0.0001] and transition zone (TZ) length [2.2 (1-3) to 2.5 (1-4), p = 0.004] were longer. Bolus clearance was inversely correlated with TZ length (p = 0.0002) and time from swallow onset to proximal smooth muscle initiation (p < 0.0001). Bolus clearance and UES characteristics were unchanged (p > 0.05). CONCLUSIONS & INFERENCES: Increased outflow resistance after LNF required an increased DCI. However, this increased contractile vigor was achieved through sustained, not stronger, peristaltic contractions. Increased esophageal length was associated with increased TZ and delayed initiation of smooth muscle contractions.

Increased risk for persistent intestinal metaplasia in patients with Barrett's esophagus and uncontrolled reflux exposure before radiofrequency ablation.

BACKGROUND & AIMS: Radiofrequency ablation (RFA) is a safe alternative to esophagectomy for patients with dysplastic Barrett's esophagus (BE). Although some studies have indicated that RFA is effective at eradicating dysplasia, most have found that RFA is not as effective in eradicating intestinal metaplasia. We investigated whether uncontrolled reflux is associated with persistent intestinal metaplasia after RFA. METHODS: Thirty-seven patients with BE underwent RFA, high-resolution manometry, and 24-hour impedance-pH testing; they received proton pump inhibitors twice daily. Patients returned every 2 months for repeat treatment or standard surveillance. Patients were classified as complete responders (CRs) if all intestinal metaplasia was eradicated in fewer than 3 ablation sessions. We analyzed clinical parameters to identify factors associated with a CR or incomplete responder (ICR). RESULTS: Among the 37 patients, 22 had a CR and 15 had an ICR. Mann-Whitney U tests revealed that length of BE, size of hiatal hernia, and frequency of reflux, but not acid reflux, differed between CRs and ICRs. CRs had fewer weakly acidic events than ICRs (29.5 vs 52; P < .05) and total reflux events (33.5 vs 60; P < .05), and a trend toward fewer weakly alkaline events (1.0 vs 5.0; P = .06). No other clinical or manometric features differed between groups. CONCLUSIONS: Uncontrolled, predominantly weakly acidic reflux despite twice-daily proton pump inhibitor therapy before RFA increases the incidence of persistent intestinal metaplasia after ablation in patients with BE. Length of BE and size of hiatal hernia also were associated with persistent intestinal metaplasia after RFA.

Comparison of esophagogastric junction distensibility changes during POEM and Heller myotomy using intraoperative FLIP.

BACKGROUND: Peroral endoscopic myotomy (POEM) is a novel endoscopic surgical procedure for the treatment of achalasia. The comparative effects of POEM and laparoscopic Heller myotomy (LHM) on esophagogastric junction (EGJ) physiology are unknown. A novel measurement catheter, the functional lumen imaging probe (FLIP), allows for intraoperative evaluation of EGJ compliance by measuring luminal geometry and pressure during volume-controlled distensions. METHODS: Distensibility index (DI) (defined as the minimum cross-sectional area at the EGJ divided by pressure) was measured with FLIP intraoperatively in patients undergoing LHM and POEM. Separate measurements were taken after each operative step. During LHM, measurements were performed after: (1) induction of anesthesia, (2) insufflation of pneumoperitoneum, (3) hiatal dissection and esophageal mobilization, (4) myotomy, (5) partial fundoplication, and (6) deinsufflation. During POEM, they were performed after: (1) induction of anesthesia, (2) submucosal tunnel creation, and (3) myotomy. RESULTS: Eleven LHM and 14 POEM patients underwent intraoperative FLIP. Baseline DI was similar between groups. LHM resulted in an overall increase in mean DI (pre 1.4 vs. post 7.6 mm(2)/mmHg, using a 40-ml distension volume; p < 0.001). Insufflation of pneumoperitoneum and hiatal dissection did not affect DI. Myotomy caused an increase in DI. Partial fundoplication (6 Toupet, 5 Dor) caused a decrease in DI, and deinsufflation caused an increase in DI. POEM also resulted in an overall increase in mean DI (pre 1.4 vs. post 7.9 mm(2)/mmHg; p < 0.001). Measured individually, both submucosal tunnel creation and myotomy caused increases in DI. When overall changes were compared, there were no differences in the amount of DI increase between LHM and POEM. CONCLUSIONS: POEM and LHM result in a similar improvement in EGJ distensibility intraoperatively. Further study is needed to correlate intraoperative FLIP measurements with postoperative symptomatic and physiologic outcomes.

Distal esophageal spasm in high-resolution esophageal pressure topography: defining clinical phenotypes.

BACKGROUND: The manometric diagnosis of distal esophageal spasm (DES) uses "simultaneous contractions" as a defining criterion, ignoring the concept of short latency distal contractions as an important feature. Our aim was to apply standardized metrics of contraction velocity and latency to high-resolution esophageal pressure topography (EPT) studies to refine the diagnosis of DES. METHODS: Two thousand consecutive EPT studies were analyzed for contractile front velocity (CFV) and distal latency to identify patients potentially having DES. Normal limits for CFV and distal latency were established from 75 control subjects. Clinical data of patients with reduced distal latency and/or rapid CFV were reviewed. RESULTS: Of 1070 evaluable patients, 91 (8.5%) had a high CFV and/or low distal latency. Patients with only rapid contractions (n = 186 [17.4%] using conventional manometry criteria; n = 85 [7.9%] using EPT criteria) were heterogeneous in diagnosis and symptoms, with the majority ultimately categorized as weak peristalsis or normal. In contrast, 96% of patients with premature contraction had dysphagia, and all (n = 24; 2.2% overall) were ultimately managed as spastic achalasia or DES. CONCLUSIONS: The current DES diagnostic paradigm focused on "simultaneous contractions" identifies a large heterogeneous set of patients, most of whom do not have a clinical syndrome suggestive of esophageal spasm. Incorporating distal latency into the diagnostic algorithm of EPT studies improves upon this by isolating disorders of homogeneous pathophysiology: DES with short latency and spastic achalasia. We hypothesize that prioritizing measurement of distal latency will refine the management of these disorders, recognizing that outcomes trials are necessary.

Many patients continue using proton pump inhibitors after negative results from tests for reflux disease.

BACKGROUND & AIMS: Ambulatory reflux testing is used to evaluate symptoms of gastroesophageal reflux disease (GERD) refractory to protein pump inhibitors (PPIs). We investigated the prevalence of PPI use in patients with negative results from Bravo pH or multichannel intraluminal impedance-pH (MII-pH) tests and factors that might predict the use of PPIs. METHODS: We analyzed data from patients who had undergone Bravo pH monitoring or MII-pH testing at Northwestern University, without evidence of reflux disease. Demographics, endoscopy findings, pathology results, and provider recommendations were obtained via chart review. Eligible patients (n = 90) were contacted by telephone, and a cross-sectional survey was administered with questions about symptom severity, demographics, medication use, and health behaviors. Patients were compared by current PPI use, and statistical analyses were performed by using SAS version 9.2 software. RESULTS: Thirty-eight patients (42.2%) reported current PPI use despite a negative result from a pH study. Only 17 patients (18.9%) recalled being instructed to stop taking PPIs; chart review showed documented instructions to stop PPI therapy for 15 patients (16.7%). There were no significant differences in demographic or clinical characteristics among patients compared by current PPI use. Patients taking a PPI were more likely than those not taking a PPI to report troublesome symptoms that affected their daily life, as measured by a questionnaire for the diagnosis of GERD (the GerdQ). CONCLUSIONS: More than 42% of patients with negative results from pH monitoring studies continue PPI therapy despite physiological data that they do not have GERD.

Phenotypes and clinical context of hypercontractility in high-resolution esophageal pressure topography (EPT).

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

High-resolution manometry studies are frequently imperfect but usually still interpretable.

BACKGROUND & AIMS: Clinical esophageal manometry can be technically challenging. We investigated the prevalence and causes of technically imperfect, high-resolution esophageal pressure topography (EPT) studies at a tertiary referral hospital. METHODS: We reviewed 2000 consecutive clinical EPT studies that had been performed with consistent technique and protocol. A study was considered technically imperfect if there was a problem with pressure signal acquisition, if the catheter did not pass through the esophagogastric junction (EGJ), or if there were fewer than 7 evaluable swallows (without double-swallowing, and so forth). Data from the technically imperfect studies were interpreted blindly to determine a diagnosis; this diagnosis was compared with the diagnosis based on chart review. RESULTS: We identified 414 technically imperfect studies (21% of the series). These were attributed to fewer than 7 evaluable swallows (58%), inability to traverse the EGJ (29%), sensor or thermal compensation malfunction (7%), and miscellaneous artifacts (6%). The most frequent causes of failure to traverse the EGJ were a large hiatal hernia (50%) and achalasia (24%). The condition most frequently associated with an incomplete swallow protocol was achalasia (33%). Despite the limitations, the diagnosis of achalasia was achieved correctly by blinded interpretation in 77% of cases and nonblinded interpretation in 94% of cases. CONCLUSIONS: Technically imperfect EPT studies are common in a tertiary care center; large hiatal hernia and achalasia were the most frequent causes. However, despite the technical limitations, the data still could be interpreted, especially in the context of associated endoscopic and radiographic data.