Relationship between some electrocardiographic parameters of ventricular repolarization and Vitamin D status in apparently healthy individuals

Background: Vitamin D (VitD) is a vitamin affective on the cardiovascular system. VitD deficiency has been related to increased cardiac and all-cause mortality even in healthy controls. Evidence showed that such relatively novel electrocardiographic (ECG) parameters of ventricular repolarization (EPVR) as Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios might be related to increase cardiac arrhythmias and even sudden cardiac death. Little data are available about the effect of VitD deficiency on EPVR. The purpose of this study was to evaluate the EPVR in apparently healthy controls with VitD deficiency.Methods: A total of 72 consecutive VitD deficient and 51 consecutive VitD nondeficient healthy controls who presented to our hospital's outpatient clinics were included in the study as two different groups. The relevant data were obtained through physical examination, electrocardiography, and echocardiography. Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were calculated from surface ECG and compared between the two groups using the Mann–Whitney U-test.Results: Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were all observed to be greater in VitD deficient group compared with the VitD nondeficient group, with robust statistical significance (68.1 ms [61.7–75.4] vs. 58 ms [54–66.2]; 0.197 [0.179–0.210] vs. 0.164 [0.147–0.187]; and 0.172 (0.156–0.191) versus 0.150 (0.137–0.164); respectively; P ≤ 0.001]).Conclusion: Our study reveals that Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio increase in VitD deficiency in apparently healthy controls, which may be related to SCD. Further studies are needed to support our results.