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Assessment of myocardial function in neonates using tissue Doppler imaging

Objective To measure the left and right ventricular myocardial velocities using tissue Doppler imaging (TDI) in the first 24 h of life in neonates. Design Left and right ventricular peak systolic (S′), early diastolic (E′) and late diastolic (A′) myocardial velocities were measured using TDI alongside standard echocardiography (including peak diastolic atrioventricular flow, E). E/E′ ratio was calculated for both ventricles. Setting UK neonatal intensive care unit. Patients 43 neonates were prospectively recruited into three groups: term (n=16), preterm (30–36 weeks, n=12) and very preterm (<30 weeks, n=15). Results Myocardial velocities increased with increasing gestation. Right ventricular velocities were significantly greater than left. E/E′ ratio decreased with increasing gestation. Left E/E′ ratio was higher than right in each group. Conclusions TDI is feasible in preterm neonates and enables the acquisition of myocardial velocities. With increasing gestation, higher myocardial velocities and lower E/E′ ratios were found. The addition of TDI to standard neonatal echocardiography may provide additional information about cardiac function.