Sleeve gastrectomy is an effective bariatric procedure, however may lead to persistent symptoms without obvious mechanical cause. The normal gastric pacemaker region, which lies on the greater curvature of the corpus, is resected in sleeve gastrectomy, however, the electrophysiological consequences are not adequately defined. This study assessed these impacts and associations with symptoms and quality of life (QoL), using non-invasive gastric mapping. Methods Patients with previous sleeve gastrectomy underwent body surface gastric mapping (Gastric Alimetry, New Zealand), comprising 30-minute fasting baseline and 4-hr post-prandial recordings. Analysis encompassed Principal Gastric Frequency (PGF), BMI-adjusted amplitude, Gastric Alimetry Rhythm Index (GA-RI), with comparison to reference intervals and matched controls. Symptoms were evaluated using a validated App and questionnaires. Results 38 patients (median 36 months post-surgery; range 6-119 months) and 38 controls were recruited. 37/38 patients had at least one abnormal parameter, typically reduced frequencies (2.4+/-0.22 vs controls 3.09+/-0.21; p<0.001) and amplitudes (28.2+/-7.1 vs 38.8+/-15.3; p<0.001). Patients also exhibited higher symptom burdens and reduced QoL (PAGI-SYM 20 vs controls 7, p<0.001; PAGI-QOL 27 vs 136, p<0.001; EQ-5D-5L 0.86 vs 0.96; p<0.01). Gastric amplitude and GA-RI were correlated positively with bloating (r=0.63 and r=0.53 respectively, p<0.01) while amplitude correlated negatively with heartburn (r=-0.43, p<0.05). Conclusion Sleeve gastrectomy modifies gastric electrophysiology due to pacemaker resection, with variable remodelling. Substantial reductions in gastric frequency and amplitude occur routinely after surgery, and specific relationships between post-sleeve gastric amplitude and symptoms of heartburn and bloating are identified.

The authors have declared no competing interest.

This work and authors were supported by the New Zealand Health Research Council, The Royal Australasian College of Surgeons John Mitchell Crouch Fellowship (GOG), the National Institutes of Health (R56 126935), and the Auckland Medical Research Foundation Douglas Goodfellow Medical Research Fellowship (THHW).

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethical approval for this study was granted by the institutional review committees of the University of Auckland, Western Sydney University and The University of Calgary Conjoint Health Research Ethics Board (AH1125, H15157, REB19-1925).

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All data produced in the present study are available upon reasonable request to the authors