Shortening of the QT interval is observed soon after sleeve gastrectomy in morbidly obese patients.

Background: Morbidly obese patients have an increased risk of sudden cardiac death. It is well known that obesity prolongs the QT interval, which in turn may cause ventricular arrhythmia and sudden cardiac death. The objective of this study was to establish whether sleeve gastrectomy shortens the QT interval.

Methods: Twenty-eight consecutive patients underwent sleeve gastrectomy at our institution between September 2010 and March 2011 and were included in the study. The indications for bariatric surgery were in accordance with French national guidelines. For each patient, an electrocardiogram was recorded before and then 3 months after surgery. The corrected QT (QTc) was determined independently by two physicians.

Results: The mean body mass index was 45.27 ± 6.09 kg/m(2) before surgery and 38.32 ± 5.19 kg/m(2) 3 months after surgery. The mean weight loss over this period was 20.71 ± 7.57 kg. The QTc interval was 427 ± 18.6 ms (415.7 ± 12.06 in men and 428.4 ± 18.96 in women) prior to surgery and was significantly lower 3 months after surgery (398.6 ± 15.5 ms overall, 391.3 ± 7.63 in men, and 399.6 ± 16.02 in women). The QTc interval decreased in all individual patients (by an average of 28.5 ± 15.6 ms overall, 24.3 ± 8.38 in men, and 29 ± 16.23 in women). Weight loss and decreased QTc interval were not significantly correlated (p = 0.88).

Conclusion: Sleeve gastrectomy in morbidly obese patients was associated with a significantly lower QTc interval 3 months after surgery. These findings imply that bariatric surgery might reduce the risk of sudden cardiac death in this patient population.