Heart disease is the primary cause of death in patients with beta-thalassemia major. The study aimed to determine the association between vitamin D and left ventricular function in patients with beta-thalassemia major with iron overload. A cross-sectional hospital-based study was conducted, where the vitamin D and ferritin levels of children living with beta-thalassemia major were measured, and left ventricular function was assessed utilizing ejection fraction (EF) and fractional shortening (FS) using 2D echocardiography. The mean serum ferritin was 4622 ± 2289 ng/ml, and the mean serum vitamin D levels were 22 ± 7.7 ng/ml. The mean values of EF were 62.30 ± 6.9%, and FS was 31.21 ± 4.8%. Statistically significant negative correlation (r = −0.447, p < 0.001) was found between vitamin D and serum ferritin values, and a significant positive association was found between vitamin D levels concerning EF and FS with a p-value of 0.034 and 0.014, respectively.Conclusion: It was observed  that increasing ferritin was associated with lower vitamin D levels which in turn influenced fractional shortening /cardiac function in these patients.  What is Known:• Patients with Beta Thalassemia major on long term transfusion are prone to develop heart disease / cardiac failure due to chronic iron overload. What is New:• Patients with beta thalassemia major on long term term transfusions with iron overload who are vitamin D deficient are more prone to the cardiac complications which inturn can be prevented by vitamin D supplementation.

Heart disease is the primary cause of death in patients with Beta Thalassemia Major. The study aimed to determine the association between vitamin D and left ventricular function in patients with Beta-Thalassemia major with iron overload. A cross-sectional hospital-based study was conducted, where the vitamin D and ferritin levels of children living with Beta Thalassemia Major were measured and left ventricular function was assessed utilizing Ejection Fraction (EF) and Fractional Shortening (FS) using 2D Echocardiography. The mean serum ferritin was 4622 ± 2289ng/ml, and the mean serum vitamin D levels were 22 ± 7.7ng/ml. The mean values of EF were 62.30 ± 6.9%, and FS was 31.21 ± 4.8%. Statistically significant negative correlation (r=-0.447, p < 0.001) was found between vitamin D and serum ferritin values, and a significant positive association was found between vitamin D levels concerning EF and FS with a p-value of 0.034 and 0.014, respectively.