3 The procedure
3.1 The aim of endoscopic radiofrequency ablation for gastro-oesophageal reflux disease is to reduce symptoms. The mechanism of action is unclear.
3.2 The procedure is usually performed with the patient under sedation. The distance to the gastro-oesophageal junction is measured endoscopically and a guidewire with a flexible tip is passed through the endoscope and left in the stomach; the endoscope is removed. A specially designed radiofrequency balloon catheter, consisting of an inflatable balloon-basket with 4 electrode needle sheaths, is inserted through the mouth over the guidewire and advanced to the gastro-oesophageal junction. The balloon is inflated to the diameter of the oesophagus and the electrodes are deployed to penetrate through the mucosa and deliver radiofrequency energy to the musculature of the lower oesophageal sphincter and the gastric cardia. Several cycles of approximately 1 minute of radiofrequency energy are delivered. These cause changes in the tissues of the lower oesophagus, but the precise mechanism of action of radiofrequency energy on the oesophagogastric junction remains a subject of debate (see section 6.1).