Slow Wave(s) of Enthusiasm: Electrogastrography as an Electrodiagnostic Tool in Clinical Gastroenterology

Excerpt

The stomach is an electrical organ. Much like in the heart, gastric depolarizations are generated in a ‘pacemaker’ region and are linked to changes in muscle contractility. In the human stomach, these pacemaker depolarizations originate in the proximal stomach and continually and slowly spread toward the pylorus through the smooth muscle syncytium at a rate of approximately three times per minute. The first electrical recordings of these ‘gastric slow waves’ were reported about 100 years ago [1], after the initial descriptions of the interstitial cells of Cajal (ICC) were published. Yet, the mechanisms of gastric slow wave generation by these ICCs and the processes involved in electromechanical coupling of slow waves to smooth muscle contractions took decades of rigorous study to understand in detail [2, 3]. Despite this continued research attention, there are gaps in the understanding of the molecular and electrophysiological basis for numerous patterns of gastric motility. Similarly, the precise pathophysiologic mechanisms driving aberrant ICC function, patterns of gastric slow wave propagation, and electrical-mechanical coherence in several chronic gastric disorders are poorly understood. Clearly, there is no shortage of challenges remaining for the field of neurogastroenterology. …