Impedance planimetry values for predicting clinical response following peroral endoscopic myotomy

Diagnostic and therapeutic strategies for achalasia of the cardia

The diagnosis of achalasia of the cardidia (AC) is primarily based on clinical symptoms, esophagographic findings, esophagodynamic examination, and upper gastrointestinal endoscopic findings. High resolution manometry is considered the gold standard for diagnosis. With the advan-cement of new technologies, the diagnostic methods for AC have become more diverse, and three-dimensional modeling may facilitate early detection of AC. The use of endoscopic functional intracavity imaging probe can enhance diagnostic accuracy. Common treatment options include endoscopic balloon dilation, laparoscopic Heller myotomy, and peroral endoscopic myotomy (POEM). POEM has emerged as the most widely utilized therapeutic approach currently, significantly improving the clinical success rate in treating AC. This article provides a comprehensive review on recent research progress in the diagnosis and treatment of AC.

Automatic three-dimensional reconstruction of the oesophagus in achalasia patients undergoing POEM: an innovative approach for evaluating treatment outcomes

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) is a standard treatment option for achalasia patients. Treatment response varies due to factors such as achalasia type, degree of dilatation, pressure and distensibility indices. We present an innovative approach for treatment response prediction based on an automatic three-dimensional (3-D) reconstruction of the tubular oesophagus (TE) and the lower oesophageal sphincter (LES) in patients undergoing POEM for achalasia.

METHODS

A software was developed, integrating data from high-resolution manometry, timed barium oesophagogram and endoscopic images to automatically generate 3-D reconstructions of the TE and LES. Novel normative indices for TE (volume×pressure) and LES (volume/pressure) were automatically integrated, facilitating pre-POEM and post-POEM comparisons. Treatment response was evaluated by changes in volumetric and pressure indices for the TE and the LES before as well as 3 and 12 months after POEM. In addition, these values were compared with normal value indices of non-achalasia patients.

RESULTS

50 treatment-naive achalasia patients were enrolled prospectively. The mean TE index decreased significantly (p<0.0001) and the mean LES index increased significantly 3 months post-POEM (p<0.0001). In the 12-month follow-up, no further significant change of value indices between 3 and 12 months post-POEM was seen. 3 months post-POEM mean LES index approached the mean LES of the healthy control group (p=0.077).

CONCLUSION

3-D reconstruction provides an interactive, dynamic visualisation of the oesophagus, serving as a comprehensive tool for evaluating treatment response. It may contribute to refining our approach to achalasia treatment and optimising treatment outcomes.

TRIAL REGISTRATION NUMBER

22-0149.

Using impedance planimetry to define the end of a peroral endoscopic myotomy

INTRODUCTION

Peroral endoscopic myotomy (POEM) is a minimally invasive endoscopic option for management of achalasia. Adequate distal myotomy is necessary for relief of symptoms, but when too long may also increase risk of reflux. The objective of this study is to evaluate clinical outcomes after POEM and final length of gastric myotomy using impedance planimetry (EndoFLIP).

METHODS

A retrospective review of 34 consecutive patients undergoing POEM with EndoFLIP were included. EndoFLIP measurements, including esophagogastric junction distensibility index (DI), minimum diameter (Dmin), and cross-sectional area (CSA) were recorded at 30- and 40-mL balloon-fill pre- and post- myotomy. The myotomy was considered complete when DI ≥ 3.4 mm2/mmHg. Postoperative Eckardt score (ES) was determined at initial postoperative visit and most recent follow-up. Linear and logistic regression were used to evaluate the association between gastric myotomy length and post-myotomy EndoFLIP measurements on postoperative ES and GERD. Wilcoxon rank-sum test was used to compare gastric myotomy lengths and EndoFLIP parameters in relation to clinical success and development of GERD, and paired t-test to compare EndoFLIP measurements and ES pre- and post-myotomy.

RESULTS

Final length of gastric myotomy measured 1 cm in 1 (2.9%), 1.5 cm in 11 (32.4%), 2.0 cm in 19 (55.9%), and 2.5 cm in 3 (8.8%) patients. Mean preoperative ES was 6.6 ± 2.2. All patients achieved ES < 3 postoperatively, which was maintained in 88.5% of patients at a median of 7.5 months of follow-up. Gastric myotomy length and post-myotomy EndoFLIP values were not associated with postoperative Eckardt scores or GERD.

DISCUSSION

Early and late symptom relief was achieved in 100 and 88.5% of patients, respectively, at a gastric myotomy length of 1-2.5 cm. Using EndoFLIP to define a completed myotomy at DI of 3.4 mm2/mmHg yielded variable lengths of gastric myotomy.

Intraoperative distensibility measurement in POEM for achalasia: impact on patient outcome and associations with other outcome variables at 1-year follow-up

BACKGROUND AND AIMS

The functional luminal imaging probe (FLIP) can provide measurements of lower esophageal sphincter (LES) distensibility. Studies report that use of intraoperative FLIP examination during peroral endoscopic myotomy (POEM) for achalasia is associated with treatment success, but evidence is limited and inconsistent. The main aim of the present study was to assess associations between intraoperative FLIP values and 1-year outcomes. Additionally, associations between 1-year FLIP measurements and other 1-year outcome variables were studied.

METHODS

We performed a single-center prospective study of consecutive achalasia patients treated with POEM with a standardized 1-year follow-up. The inclusion period was from June 2017 to January 2020. We compared 1-year outcomes (FLIP measurement values, Eckardt score (ES), reflux esophagitis, timed barium esophagogram (TBE), and lower esophageal sphincter resting pressure (LES-rp)) in patients with and without intraoperative FLIP examination. We also assessed associations between intraoperative FLIP values, 1-year FLIP values, and other 1-year outcomes. Results are given as median (IQR), and non-parametrical statistical analyses were applied.

RESULTS

Sixty-two patients (27 females) with median age 45 years (35-54) were included. Baseline characteristics were similar in patients with (n = 32) and without (n = 30) intraoperative FLIP examination. In patients with intraoperative FLIP, ES was 2 (1-3) and LES distensibility index (DI) 3.7 (2.6-5.4) after 1 year, compared with ES 2 (1-3) and DI 4.0 (3.1-6.8)) in patients without intraoperative FLIP (ns). Intraoperative DI was not correlated with 1-year ES or DI. One-year DI correlated significantly with 1-year ES (rs - 0.42), TBE (rs - 0.34), and LES-rp (rs - 0.29).

CONCLUSIONS

Use of intraoperative FLIP measurements in POEM for achalasia is not associated with improved 1-year outcome, and the clinical value of intraoperative FLIP in POEM for achalasia is questioned. Follow-up FLIP measurements are moderately associated with symptomatic outcome, and may serve as an additional diagnostic modality in post-treatment evaluation.

Role of short interval FLIP panometry in predicting long-term outcomes after per-oral endoscopic myotomy

BACKGROUND

The Eckardt score (ES) is used to assess symptom response to Per-Oral Endoscopic Myotomy (POEM), but reliable methods to assess physiologic success are needed. Functional lumen imaging probe (FLIP) panometry has a potential role in post-POEM follow-up to predict long-term outcomes. The aim of this study was to assess the correlation between clinical success and FLIP parameters following POEM to determine if short interval FLIP could predict long-term outcomes.

METHODS

This was a prospective study of adult patients who underwent POEM with short interval follow-up FLIP between 11/2017 and 3/2020. Clinical success was defined as post-procedure ES ≤ 3. Physiologic success was based on an esophago-gastric junction distensibility index (EGJ-DI) > 2.8 mm2/mmHg on FLIP.

RESULTS

47 patients (55% female, mean age 55 years) were included in the study. Clinical success after POEM was seen in 45 (96%) patients (mean ES 6.5 ± 2.2 pre and 0.83 ± 1.0 post-POEM, p < 0.001). Physiologic success was noted in 43 (91.5%) patients (mean EGJ-DI 6.1 mm2/mmHg ± 2.5). Among 4 patients not meeting criteria for physiologic success, EGJ-DI was 2.5-2.6. There was no correlation between post-POEM EGJ-DI and ES in the short term or long term. Significant reflux esophagitis was seen in 6 (12.8%) patients with no difference in mean EGJ-DI with vs without esophagitis (5.9 vs 6.1, p = 0.44).

CONCLUSION

Post-POEM endoscopy with FLIP is useful to both assess EGJ physiology and to examine for reflux esophagitis. Short interval FLIP has limited utility to predict long-term patient outcomes or risk of acid reflux.

Comparison of functional lumen imaging probe and high-resolution manometry to assess response after peroral endoscopic myotomy

BACKGROUND AND AIMS

Outcomes after peroral endoscopic myotomy (POEM) are assessed clinically by the Eckardt score (ES) or objectively by high-resolution manometry (HRM) and functional lumen imaging probe (FLIP). This study compared HRM and FLIP to evaluate clinical response after POEM.

METHODS

This was a single tertiary center retrospective study of consecutive patients who underwent POEM for treatment-naive achalasia and with ≥6 months of follow-up. Baseline and follow-up testing in all patients included ES, HRM, and FLIP of the esophagogastric junction (EGJ). A normal post-POEM (or normalized) EGJ distensibility index (EGJ-DI) >2.8 mm²/mm Hg, maximum EGJ diameter (MxEGJD) ≥14 mm, and integrated relaxation pressure (IRP) <15 mm Hg were compared with a clinical response, defined as ES ≤3.

RESULTS

Eighty-seven patients (58% men, mean age 51 ± 17 years) were included. Overall clinical response by ES, IRP, MxEGJD, and EGJ-DI were 97.7%, 86.2%, 75.9%, and 92.0%, respectively. The sensitivity of a normal IRP (87.1% [95% confidence interval {CI}, 78.0-93.4]) was similar to the sensitivity of a normal MxEGJD (75.3% [95% CI, 64.7-84.0], P = .053) and normal EGJ-DI (91.8% [95% CI, 83.8%-96.6%], P = .39) after POEM to predict clinical response. However, the sensitivity of a normal post-POEM EGJ-DI was superior to a normal post-POEM MxEGJD (P = .001) to predict clinical response. There was no difference in the area under the curve of a normal MxEGJD or EGJ-DI to predict a normal IRP (P = .956) after POEM.

CONCLUSIONS

Normal FLIP metrics ≥6 months after POEM for achalasia show good to excellent sensitivity but are equivalent to a normalized IRP by HRM to predict clinical response by ESs. FLIP may be used as an alternative to HRM to assess lower esophageal sphincter response to POEM in these patients. (Clinical trial registration number: NCT02770859.).

Insights into the endoscopic management of esophageal achalasia

Achalasia is a primary esophageal motility disorder characterized by the loss of inhibitory neurons in the myenteric plexus, resulting in impaired relaxation of the esophagogastric junction. Achalasia is an incurable disease, and the treatment modalities are aimed at disruption of the esophagogastric junction and vary widely from pharmacological to endoscopic to surgical. Traditional endoscopic therapy includes pneumatic dilation, botulinum toxin injection, and peroral endoscopic myotomy. This review aims to provide an overview of the endoscopic management of achalasia, while focusing on the utilization of peroral endoscopic myotomy and other novel approaches.