Ablation for Barrett’s esophagus does not impair esophageal motility
MedWire News: Ablative techniques used to treat Barrett's esophagus do not impair esophageal motility, but may decrease the ability of the esophagus to detect acidity, researchers in the UK have shown.
"The clinical importance of Barrett's esophagus, whereby the native esophageal squamous epithelium is replaced with specialized columnar cells, is the strong association with the development of adenocarcinoma of the esophagus," explain Anne Smythe (Royal Hallamshire Hospital, Sheffield) and colleagues.
Barrett's esophagus is usually preceded by chronic gastric acid reflux, but it is still unclear whether this is related to the poor esophageal motility usually seen in patients with the Barrett's esophagus.
Ablative techniques, such as argon plasma coagulation (APC) in which ionized argon gas is used to ablate via an endoscopic catheter, has been shown to effectively treat Barrett's esophagus. However, whether APC affects esophageal motility is unknown.
Smythe and co-workers therefore assessed esophageal motility and sensitivity to acid in 20 patients with Barrett's esophagus, before and after APC therapy.
Specifically, the researchers used pressure sensors on catheters (pull-through manometry) to measure gastric pressure and primary and esophageal peristalsis in response to air and water before and after APC treatment. The scientists also measured the response of the esophagus to an acid solution.
Patients were endoscopically reviewed 4-6 weeks after ablative treatment and further APC therapy was performed if necessary. A maximum of five APC sessions were performed. Biopsies were taken if endoscopic examination showed no macroscopic evidence of Barrett's esophagus. Repeat esophageal motility and sensitivity studies were carried out 4-6 weeks following successful ablation.
As reported in the journal Diseases of the Esophagus, APC had no significant effect on low esophageal sphincter pressure or how efficiently patients could swallow. Secondary peristalsis did improve after treatment, with an air bolus of 0 before treatment versus 2 after treatment and a respective water bolus of 0 versus 1, but the improvement was not statistically significant.
In addition, the sensitivity of the esophagus to acid (61 vs 31) and alkali (91 vs 64) significantly decreased.
Discussing their findings, the authors suggest that the mucosal nerve damage caused by APC was responsible for the decrease in the sensitivity of the esophagus to acid and alkali, and that this may have resolved if patients had been given more time to heal.
The investigators point out that their results agree with those from previous studies that showed some improvement in secondary peristalsis after ablative therapy, an observation that "has implications for reflux clearance after treatment," they write.
Concluding, the researchers suggest that "the complex interaction between the mucosa, mileau, and the physiological response needs further investigation."
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By Philip Ford