Gastric Alimetry(R) improves patient phenotyping in gastroduodenal disorders compared to gastric emptying scintigraphy alone

ObjectivesGastric emptying testing (GET) assesses gastric motility, however is non-specific and insensitive for neuromuscular disorders. Gastric Alimetry(R) (GA) is a new medical device combining non-invasive gastric electrophysiological mapping and validated symptom profiling. This study assessed patient-specific phenotyping using GA compared to GET. MethodsPatients with chronic gastroduodenal symptoms underwent simultaneous GET and GA, comprising a 30-minute baseline, 99mTC-labelled egg meal, and 4-hour postprandial recording. Results were referenced to normative ranges. Symptoms were profiled in the validated GA App and phenotyped using rule-based criteria based on their relationships to the meal and gastric activity: i) sensorimotor; ii) continuous; and iii) other. Results75 patients were assessed; 77% female. Motility abnormality detection rates were: GET 22.7% (14 delayed, 3 rapid); GA spectral analysis 33.3% (14 low rhythm stability / low amplitude; 5 high amplitude; 6 abnormal frequency); combined yield 42.7%. In patients with normal spectral analysis, GA symptom phenotypes included: sensorimotor 17% (where symptoms strongly paired with gastric amplitude; median r=0.61); continuous 30%; other 53%. GA phenotypes showed superior correlations with GCSI, PAGI-SYM, and anxiety scales, whereas Rome IV Criteria did not correlate with psychometric scores (p>0.05). Delayed emptying was not predictive of specific GA phenotypes. ConclusionsGA improves patient phenotyping in chronic gastroduodenal disorders in the presence and absence of motility abnormalities with improved correlation with symptoms and psychometrics compared to gastric emptying status and Rome IV criteria. These findings have implications for the diagnostic profiling and personalized management of gastroduodenal disorders. Study Highlights1) WHAT IS KNOWN O_LIChronic gastroduodenal symptoms are common, costly and greatly impact on quality of life C_LIO_LIThere is a poor correlation between gastric emptying testing (GET) and symptoms C_LIO_LIGastric Alimetry(R) is a new medical device combining non-invasive gastric electrophysiological mapping and validated symptom profiling C_LI 2) WHAT IS NEW HERE O_LIGastric Alimetry generates a 1.5x higher yield for motility abnormalities than GET C_LIO_LIWith symptom profiling, Gastric Alimetry identified 2.7x more specific patient categories than GET C_LIO_LIGastric Alimetry improves clinical phenotyping, with improved correlation with symptoms and psychometrics compared to GET C_LI