Correlation of myocardial performance index and serum ferritin levels in children with beta thalassemia major

Abstract

Background: Cardiac complications are the major causes of mortality and morbidity in β Thalassemia major. Early recognition of cardiac iron overload by 2D and Doppler echocardiography which is economical guides early intervention and hence minimise morbidity and mortality. The objective of the study was assessment of myocardial performance index (MPI) and serum ferritin (SF) in children with β-Thalassemia and to establish relation of myocardial performance index in to serum ferritin level and age. Methods: A Cross -sectional descriptive analytical study including 34 patients in the age group 3 years to 17 years with β-thalassemia on regular blood transfusion were included in the study. M-mode, 2D and Doppler echocardiography is used for analysis of isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), ejection time (ET) and MPI. SF was measured by ELISA. Results: Mean age was 9.21(+/-3.9) years. SF ranged from 365 to 18826µg/L. MPI varied from 0.35 to 0.62. Similarly IVRT varied from 35ms to 74 ms (60.26+/-12.36ms), IVCT from 36 to 75ms, ET from 108 to 280ms. MPI was 0.39±0.04 (Mean±SD) at SF≤1000 µg/L against 0.49±0.04 at SF of 1000 µg/L to 2499 µg/L. Rate of increase of MPI was maximum from SF 582 µg/L to 1962µg/L. Conclusions: Mean MPI is abnormal at SF levels more than 1000 µg/L. Although MPI value is within the normal limit for the age at SF levels less than 1000 µg/L, MPI starts increasing with increasing SF from as low as 582 µg/L. Serial evaluation could give better information even if myocardial performance index falls within normal range for the age.