THE GASTROESOPHAGEAL FLAP VALVE - IN-VITRO AND IN-VIVO OBSERVATIONS

Background: This study was performed to confirm the presence and signi ficance of a gastroesophageal flap valve. Methods: The pressure gradie nt needed to induce reflux across the gastroesophageal junction and th e level of a high-pressure zone were determined in 13 cadavers. On ins pection in the cadavers, a mucosal flap valve at the entrance of the e sophagus into the stomach was seen through a gastrostomy. This valve w as deficient or absent in cadavers with a hiatal hernia. The valve was inspected in controls and in patients with reflux with a retroflexed endoscope. Results: In cadavers with no hiatal hernia, a gradient acro ss the gastroesophageal junction was present in nearly all cadavers. T he gradient could be increased by surgically accentuating the valve wi thout a concomitant rise in pressure in the high-pressure zone. Reduct ion of the hiatal hernia in the cadaver and anchoring of the gastroeso phageal junction to the normal attachment to the preaortic fascia rest ored the valve and the gradient as seen through a gastrostomy. Control subjects had a prominent fold of tissue that extended 3 to 4 cm along the lesser curve of the stomach and tightly grasped the shaft of the endoscope. This was diminished or absent in reflux patients. Inspectio n of the valve in control subjects and subjects with reflux allowed fo r a grading system with Grades I through IV. This grading system was a pplied to a cohort of patients with and without reflux. The appearance of the flap valve was a better predictor of the presence or absence o f reflux than was lower esophageal sphincter pressure. Endoscopic view ing of the valve during surgery can confirm that a competent valve has been reconstructed. Conclusions: Grading of the gastroesophageal valv e is simple, reproducible, and offers useful information in the evalua tion of patients with suspected reflux undergoing endoscopy.