Objective: Obesity is associated with adverse alterations in ventricular repolarization and increased electrophysiological heterogeneity. Sleeve gastrectomy provides substantial and sustained weight loss; however, its effects on ventricular repolarization parameters assessed by surface electrocardiography (ECG) remain incompletely characterized. The aim of this study was to evaluate the effect of weight loss after sleeve gastrectomy on ventricular repolarization parameters assessed by surface ECG.
Materials and
Methods: This retrospective study included 95 morbidly obese patients who underwent laparoscopic sleeve gastrectomy. Standard 12-lead electrocardiograms were evaluated preoperatively and during routine follow-up approximately 6 months after surgery. Changes in ventricular repolarization parameters were analyzed in relation to post-operative weight loss.

Results: Substantial weight loss was observed at follow-up. Among time-based electrocardiographic parameters, modest but statistically significant post-operative reductions were detected in corrected QT interval (QTc), QT interval dispersion (QTd), and corrected JT interval (JTc), while all values remained within generally accepted physiological ranges. In addition, ratio-based indices reflecting relative depolarization-repolarization timing, including Tpeak–Tend dispersion/QT and QRS duration/QT, showed significant post-operative decreases. No significant post-operative changes were observed in other ventricular repolarization parameters.

Conclusion: Weight loss following sleeve gastrectomy was associated with subtle changes in selected ventricular repolarization parameters detectable on surface ECG, suggesting limited electrophysiological adaptation rather than overt alterations in myocardial conduction or repolarization. The clinical implications of these findings remain uncertain, and further prospective studies with longer follow-up are warranted to clarify the electrophysiological effects of sleeve gastrectomy.