Flow across the gastro-esophageal junction: lessons from the sleeve sensor on the nature of anti-reflux barrier.

The principles of fluid flow are critical to the understanding of flow across the gastro-esophageal (GE) junction or gastro-esophageal reflux. The mechanism by which sleeve sensor measures lower esophageal sphincter (LES) pressure is also based on the principle of fluid flow across the GE junction and can provide important insights into the nature of anti-reflux barrier. We present arguments regarding the role of the length of LES, intra-abdominal length of the LES, flap valve at the GE junction and the angle of His on the strength of anti-reflux barrier. Our conclusion is that in the presence of normal anatomy of the GE junction (absence of hiatus hernia) the pressure at the GE junction is the most important determinant of the strength of anti-reflux barrier.