THE MYSTERY OF THE ANGLE OF HIS

The internist Wilhelm His (1863-1934) was born as one of six children to the esteemed anatomist and physiologist of the same name, Wilhelm His. Several significant discoveries, particularly regarding the heart's conduction system, are named after him.

However, he also dedicated himself to the question of reflux. He noticed that the stomach, when viewed from the front and with an intact diaphragm, is always positioned at an acute angle to the esophagus. The reason for this is that the esophagus enters the stomach slightly laterally rather than directly at the top. The resulting angle, which varies significantly among individuals, is approximately between 30 and 70 degrees.

He observed during autopsies that in reflux patients, on one hand, the stomach had slid upwards through the diaphragm, and on the other hand, that this angle had indeed changed: the higher the stomach ascended, the flatter the angle became.

Could this angle possibly be significant for reflux control? Was the flattening not merely an insignificant consequence of organ displacement, but did it actually influence reflux control?

Back then, as well as today, this was a fascinating hypothesis for the medical community. Everything now seemed so simple. For both then and now, researchers found no signs of any disease or muscle weakness in microscopic examinations of the esophagus. There was also no evidence of a malfunctioning or even any sphincter that could be relaxed. The organs were healthy and unremarkable; they were simply displaced. The only anatomically identifiable change was this altered angle. Therefore, the professor named it the "His angle."

Nevertheless, a heated discussion broke out, as always happens when no one really knows anything. Based on this hypothesis, the first surgeries to correct the His angle were performed. The anticipation was high, but the results were disappointing: the patients experienced as much reflux after the surgery as they had before.

Then, Allison et al. highlighted a crucial point in their research: the importance of the diaphragm! Allison described the diaphragmatic crura as stable pillars essential for the organization of the organs. When the diaphragm breaks, this important anchor is lost, and the organs shift.

We can confirm this fundamental insight today through our own research. How close the colleagues of that time came to the truth, and how they might have spared medicine the misguided path of esophageal wrapping and fundoplication! However, there was no cardiac MRI back then, as there is today. Therefore, the colleagues could not yet recognize the interlocking interplay of the beating heart, diaphragm, and esophagus.

Today we know that the His angle, as discovered back then, actually has nothing to do with natural reflux control. It merely indicates that the organs are displaced in their positions. Nothing more.

Therefore, it is essential to capture and correct the arrangement and interaction of the organs in three dimensions across different planes. When the organs are anatomically returned to their proper positions, their function returns. The His angle also normalizes because everything is now where it belongs.

PD Dr.med. Eckhard Löhde