Characterisation of Gastric Conduit Electrophysiology in Post-Oesophagectomy Patients Using High-Resolution Body Surface Gastric Mapping

BACKGROUND: Oesophagectomy with gastric conduit reconstruction is associated with long-term morbidity, yet mechanisms underlying post-operative gastric dysfunction remain incompletely understood. This study evaluated gastric myoelectrical activity in the reconstructed intrathoracic stomach using non-invasive body-surface gastric mapping (BSGM) and examined its relationship with symptoms and delayed gastric conduit emptying (DGCE). METHODS: Thirty adults who were at a median of 50.4 months post-oesophagectomy were recruited and compared with 30 matched controls. All participants underwent BSGM recordings. Patient-reported outcomes were assessed using PAGI-SYM, PAGI-QoL, total symptom burden score, and Konradsson's DGCE score. Electrophysiological metrics were compared with matched controls. Pearson correlations and ANOVA with correlation ratio were used to assess associations between electrophysiology, symptoms, and DGCE. RESULTS: Post-oesophagectomy patients demonstrated significantly impaired gastric electrophysiology, including reduced principal gastric frequency (2.65±0.37 vs. controls 3.11±0.24cpm, p<0.001) and BMI-adjusted amplitude (27.1±11.1 vs. 40.5±17.3 µV, p<0.001). Twenty-three patients (76.7%) exhibited abnormal BSGM phenotypes, most commonly low-frequency activity (n=13). DGCE was present in 23.3% of patients and was associated with higher symptom burden and reduced quality-of-life (PAGI-SYM r=0.37,p<0.05; PAGI-QOL r=-0.41,p<0.05). Principal gastric frequency was found to correlate with nausea (r=0.49,p<0.05), and BMI-adjusted amplitude correlated with symptoms of excessive fullness (r=0.49,p<0.05) and upper gut pain (r=0.48,p<0.05). CONCLUSION: The gastric conduit exhibits persistent electrophysiological abnormalities years after oesophagectomy, characterised by low-frequency slow-wave activity and reduced amplitude. While these abnormalities showed some association with symptom burden, they did not correlate with DGCE, indicating this is multifactorial. BSGM provides insight into post-oesophagectomy gastric function and could inform therapeutic strategies.