Correlation between serum vitamin D level and cardiac function: Echocardiographic assessment

Abstract

Background: The association between vitamin D and cardiovascular-diseases especially cardiac function is widely debated. Aim of work: To study the relation between serum 25-hydroxy vitamin D levels and parameters of cardiac systolic and diastolic functions in patients with LV systolic heart failure. Patients and methods: The study included 60 patients admitted to our hospital for management of symptomatic heart failure with systolic dysfunction (ejection fraction <40%). Venous samples were taken to measure serum 25-hydroxy vitamin D. Trans-thoracic echocardiography was done for all patients and parameters of systolic and diastolic functions were taken. Results: Compared to patients with vitamin D ≥20 ng/ml, patients with vitamin D level <20 ng/ml had significantly higher average e', significantly shorter isovolumetric relaxation time (IVRT), and significantly lower E/e', which is suggestive of a better diastolic function. While, also compared to patients with vitamin D ≥20 ng/ml, patients with vitamin D level <20 ng/ml had higher end systolic volume (ESV) (p= 0.05), larger end systolic dimension (ESD) (p= 0.056), higher interventricular septum (IVS) thickness (p< 0.001), higher posterior wall (PW) thickness (p< 0.001), higher mean LV wall thickness (p< 0.001), and higher LV mass (p= 0.05). Conclusion: Vitamin D exerts biphasic effect on cardiac function according to its serum levels. Reduced vitamin D (<20 ng/ml) appears to be associated with worse systolic functions in terms of end systolic volume and end systolic dimension. Higher vitamin D levels (≥20 ng/ml), however, seem to be linked to worse LV diastolic functions in terms of lower e', higher E/e' and longer IVRT.