Findings support potential of FLIP
“The endoscopic FLIP is an exciting clinical tool that utilizes distension of a catheter-mounted balloon to different volumes to acquire esophageal dimensions and pressures,” Amit Patel, MD, of Duke University, Durham, N.C., said in an interview.
Amit Patel, MD
“Accumulating data on FLIP inspired [recently published guidelines] to suggest the use of FLIP to complement high-resolution manometry in the setting of obstructive esophageal symptoms and borderline HRM findings, for patients in whom an HRM study cannot be completed, and for intraprocedural use during interventions for achalasia,” Dr. Patel said. “However, the comparative utility of FLIP, particularly among foundational esophageal diagnostics such as HRM and TBE, is less well developed at this point.”
Dr. Patel said he was surprised by some of the findings. “The characteristics of FLIP metrics (specifically, EGJ–distensibility index <2 mm2/mm Hg and/or maximum EGJ diameter <12 mm) were numerically superior to those for traditional IRP metrics from HRM in predicting retention on TBE on AUROC, regression analyses, and discordant cases in this study,” said Dr. Patel. “Although this study also corroborated the value of IRP on HRM, these findings were somewhat surprising for HRM, given its well-earned reputation as the gold standard for the diagnosis of esophageal motor disorders, its widespread use, and the record of strong data supporting its important role in clinical practice.”
Overall, this study suggests these metrics from FLIP (namely, EGJ–distensibility index and EGJ diameter) may have “diagnostic value beyond traditional IRP metrics from HRM to identify objective retention on TBE,” said Dr. Patel, who also said these exciting findings “support the growth of the complementary role of FLIP ... particularly in cases where HRM may be inconclusive or not tolerated by patients.”
However, more research is needed. “Taking into account other HRM metrics beyond IRP, such as intrabolus pressures or evaluation of bolus transit on impedance, and provocative maneuvers on HRM, such as rapid drink challenges or solid swallows, may be appropriate for further evaluation, as will improved arbitration of ‘borderline’ metrics or less clear cases,” Dr. Patel emphasized. Future studies should also incorporate management interventions and assessments of outcomes.
The study was supported by a grant from the Public Health service to a coinvestigator, and by the American College of Gastroenterology Junior Faculty Development Award to lead author Dr. Carlson. Dr. Carlson also disclosed speaking and consulting relationships with Medtronic, which manufactures FLIP panometry systems. Northwestern University and several coauthors also disclosed intellectual property rights and ownership surrounding FLIP panometry systems, methods, and apparatus with Medtronic. Dr. Patel had no financial conflicts to disclose.
This article was updated Oct. 13, 2021.