The gastro-œsophageal ‘sphincter’ and the mechanism of regurgitation

Heartburn in Late Pregnancy. Manometric Studies of Esophageal Motor Function*

“…Increased intragastric pressure is the most obvious: the enlarging uterus allows less room for stomach contents. Many pregnant women experience symptoms of reflux when bending or stooping, actions which result in a sharp rise in intragastric pressure (20). Such a rise in pressure alone might be responsible for reflux, but while the fundal esophageal pressure gradient increased in most pregnant subjects as the uterus enlarged, the women in whom reflux occurred had no higher intragastric pressure than those without reflux, nor did Creamer find that the fundal esophageal pressure gradient rose during spontaneous reflux in nonpregnant subjects (15).…”

Endoscopic augmentation of the cardia with a biocompatible injectable polymer (Enteryx) in a porcine model

“…Swallowing of air or food results in gastric dilatation, increased intragastric pressure, and unfolding of the sphincter area. When the stomach is distended, the vectors produced by gastric wall tension pull on the gastroesophageal junction with a force that varies according to the geometry of the cardia; that is, the forces are applied more directly when a hiatal hernia exists than when a proper angle of His is present [5]. Indeed, there is a close relationship between the degree of gastric distention necessary to overcome the highpressure zone and the morphology of the cardia [4].…”

“…In early disease or normal subjects, this is usually due to a transient loss of the high-pressure zone. Transient loss is usually caused by a functional problem of the gastric reservoir [5,16]. Swallowing of air or food results in gastric dilatation, increased intragastric pressure, and unfolding of the sphincter area.…”

Hiatal Hernia in Bronchial Asthma

“…The importance of the right crus of the diaphragm has been emphasized by several authors [2,9,39] although some workers do not attach much value to this [5,7,18,49]. The mucous membrane in the cardiac region of the stom ach is said to be quite mobile [26,59] and to exert a valve mechanism [7,21,22,47,54].…”

“…The muscle fibres lying obliquely on the upper angle of the stomach, between the oesophagus and the fundus, arc said to play some part in the valve mechanism [7]. The pressure difference between thorax and abdomen exerts its influence on the viscera, especially on the gullet and stomach [21,65], Experimental work has been done in this respect [5,6,22,29,38,49]. According to Dornhorst.…”