The relationship between vitamin B12 levels and electrocardiographic ventricular repolarization markers.

Background: it has been shown that vitamin B12 deficiency, which can cause hematological and neuropsychiatric disorders, may also be associated with cardiac autonomic dysfunction, heart rate variability, endothelial dysfunction, and a decrease in myocardial deformation. Aims: the aim of our study is to evaluate the relationship between vitamin B12 levels and electrocardiographic repolarization disorders, which are indicators of arrhythmogenic predisposition in healthy individuals. Methods: our study population consisted of 214 healthy adults. Considering the distribution of vitamin B12 levels and accepting 25 % and 75 % percentiles as the cut-off values, the participants were divided into 3 groups. Laboratory, echocardiography and electrocardiography (ECG) measurements were compared between three groups. ECG measurements were performed manually and Tpeak-Tend (Tp-e), Tp-e corrected (Tp-ec), QT and QT corrected (QTc) intervals were calculated. Results: the patients in Group 1 (vitamin B12 < 253 pg/ml) were found to have significantly higher QT and QTc dispersions, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios when compared to those in Group 2 (253 pg/ml < vitamin B12 > 436 pg/ml) and Group 3 (vitamin B12 > 436 pg/ml). On the other hand, a negative significant correlation was detected between vitamin B12 levels and Tp-e, Tp-e/QT, Tp-e/QTc ratios, QT and QTc dispersions. Conclusion: a low level of vitamin B12 in healthy individuals can be a significant indicator of arrhythmogenic susceptibility. A close follow-up of these subjects in terms of arrhythmogenic predisposition can be useful. [ABSTRACT FROM AUTHOR]