A wearable, non-invasive system was developed to monitor electrical activity in the stomach over 24 hours — essentially an electrocardiogram for the gastro-intestinal (GI) tract. Monitoring for longer periods of time also increases the likelihood of capturing abnormal events.
The device is a 3D-printed portable box connected to ten small, wearable electrodes. Data collected with the wearable system were comparable to data collected in a clinic with state-of-the-art methods that are invasive, including a catheter inserted through the patient’s nose. The stomach’s electrical activity changes not only around meals, but also during sleep, following its own circadian rhythm.
The device could enable a gastroenterologist to quickly see where and when a part of the GI tract is showing abnormal rhythms, and as a result, make more accurate, faster, and personalized diagnoses. It can help determine if the stomach is functioning properly during meals and, most importantly, when patients are experiencing symptoms such as nausea and belly pain.
The major challenge was designing algorithms that recognize and boost the stomach’s electrical signals amid noise and artifacts. This is especially difficult to do because the stomach’s electrical signals are ten times weaker than the heart’s, making them harder to capture and analyze. The algorithmic pipeline cleans up the data and separates out abdominal muscle activity (for example, when a person walks), heartbeats, and gastric activity into different bands of signals that do not overlap. As a result, clinicians can examine each signal individually and compare it to others.
The device uses off-the-shelf electrodes used in electrocardiograms. The electronics and battery are encased in a 3D-printed box and connected to the electrodes, which fit on a person’s abdomen just over the stomach. It is paired with a smartphone app that allows patients to log their meals, sleep, and other activities. The long-term goal is to design an app that would allow patients and physicians to see the data collected by the device in real time.
Healthy people could also benefit from using the device. Competitive athletes and their coaches could monitor GI activity to figure out the best time for meals, especially while traveling across different time zones. Pregnant women suffering from heartburn and other GI problems could use it to monitor the stomach’s activity before, during, and after meals, as would the elderly.