Effect of vitamin d replacement on atrial electromechanical delay in subjects with vitamin d deficiency

AEMD and Vitamin D Deficiency Objectives Limited data are available regarding cardiac arrhythmias in vitamin D (VitD) deficiency. Therefore, we aimed to assess whether atrial electromechanical delay (AEMD) measured by tissue Doppler imaging (TDI), which is an indicator for atrial fibrillation (AF) development, is prolonged in patients with VitD deficiency as compared to the control group. The effect of vitD replacement on AEMD was also evaluated. Methods In this prospective study a total of 28 VitD-deficient and 56 age-, gender-, and BMI-matched VitD-sufficient healthy participants were enrolled. P-wave dispersion (PWd) was calculated on the 12-lead electrocardiogram. Both intra- and inter-AEMD were calculated by TDI. Measurements were performed at baseline in both groups and were repeated after 6-month replacement therapy in subjects with vitD deficiency. Results PWd and inter- and left intra-AEMD were significantly prolonged in patients with VitD deficiency compared to the control group (P < 0.001). While serum 25(OH)D levels were significantly and negatively correlated with left intra-AEMD (r = -0.657, P < 0.001), there was a positive correlation between serum 25(OH)D level and PWd (r = 0.523, P < 0.001). The serum 25(OH)D level was found as the independent predictor of the both left intra- and inter-AEMD in the multivariate linear regression analysis (β:-0.552, P < 0.001 and β:-0.555, P < 0.001, respectively). The serum 25(OH)D level was significantly increased after replacement therapy. While inter-AEMD was significantly decreased (P = 0.013), there was no change in PWD and left and right intra-AEMD (P > 0.05) following replacement therapy. Conclusion PWd and left intra- and inter-AEMD are increased in patients with VitD deficiency. The serum 25(OH)D level was found as an independent predictor for AEMD in patients with VitD deficiency. Also a significant decrement was observed in inter-AEMD following vitD replacement therapy. Studies with longer follow-up are needed to investigate whether vitD-deficient patients with prolonged AEMD develop clinical arrhythmia and vitD replacement reduces the risk of atrial arrhythmias.