1 Deo R.

Katz R.

Shlipak M.G.

et al. Vitamin D, parathyroid hormone, and sudden cardiac death: results from the Cardiovascular Health Study.

2 Drechsler C.

Pilz S.

Obermayer-Pietsch B.

et al. Vitamin D deficiency is associated with sudden cardiac death, combined cardiovascular events, and mortality in haemodialysis patients.

1 Deo R.

Katz R.

Shlipak M.G.

et al. Vitamin D, parathyroid hormone, and sudden cardiac death: results from the Cardiovascular Health Study.

2 Drechsler C.

Pilz S.

Obermayer-Pietsch B.

et al. Vitamin D deficiency is associated with sudden cardiac death, combined cardiovascular events, and mortality in haemodialysis patients.

3 Dobnig H.

Pilz S.

Scharnagl H.

et al. Independent association of low serum 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels with all-cause and cardiovascular mortality.

4 Goldberger J.J.

Cain M.E.

Hohnloser S.H.

et al. American Heart Association/American College of Cardiology Foundation/Heart Rhythm Society scientific statement on noninvasive risk stratification techniques for identifying patients at risk for sudden cardiac death: a scientific statement from the American Heart Association Council on Clinical Cardiology Committee on Electrocardiography and Arrhythmias and Council on Epidemiology and Prevention.

5 Huikuri H.V.

Exner D.V.

Kavanagh K.M.

et al. Attenuated recovery of heart rate turbulence early after myocardial infarction identifies patients at high risk for fatal or near-fatal arrhythmic events.

Vitamin D deficiency is associated with an increased risk of cardiovascular events []. In particular, deficiency in both 25hydroxyvitamin D, the barometer of vitamin D status, and 1,25dihydroxyvitamin D, the activated form of vitamin D, are each associated with an increased risk of sudden arrhythmic death []. The assessment of heart rate variability (HRV), particularly its vagal component, is strongly linked to the development of serious cardiovascular events, including sudden death []. It is well recognized that impaired autonomic tone is central in the development of sudden arrhythmic death and that dynamic changes in autonomic tone appear central in the cascade of events common to the development of a cardiac arrest [].