[Comparison of left and right ventricular pulsed and tissue Doppler myocardial performance index values using Z-score in newborns with hypoxic-ischemic encephalopathy].

OBJECTIVE

The aim of the study is determination of myocardial performance index (MPI/Tei index) using pulsed (PD) and tissue Doppler (TD) techniques to show cardiac response in newborns with hypoxic-ischemic encephalopathy (HIE) and healthy newborns and eventually evaluation of the differences between these two techniques.

METHODS

The study is a prospective observational study. Twenty term newborns diagnosed as perinatal asphyxia during postnatal 24 hours due to the defined criteria and fifty healthy term neonates as control group were included the study. Hypoxic group was divided into two groups with Sarnat stages, Sarnat Stage 1 and 2-3. MPIs (Tei indexes) were calculated with PD and TD echocardiographic techniques in all groups after the 24 hours of birth and one year later. The statistical differences between same techniques were calculated with Kruskal-Wallis test and Z score was used to compare the superiority of two techniques.

RESULTS

The MPI values calculated by PD (0.41±0.04, 0.51±0.02) and TD (0.59±0.04, 0.51±0.02) during the first day of life in Sarnat Stage 2-3 in both ventricles were significantly higher than the control group (p<0.01, p<0.02, p<0.03). While the Z score, calculated for MPI measured by PD and TD methods, were found similar in both ventricles in Sarnat Stage 1 and control groups, it was significantly different in other groups of Sarnat stages.

CONCLUSION

The degree of cardiac response in neonates with HIE is associated with the severity of hypoxia. MPI values are not different from the controls in newborns received mild hypoxia while they are higher in the patients who were received moderate or severe hypoxia. Any advantage could not be found between two techniques according to the measurement values, but higher variability in the value of MPI, measured by TD method, calculated from moderate and severe hypoxia group was detected.