Longitudinal systolic left ventricular function in preterm and term neonates: reference values of the mitral annular plane systolic excursion (MAPSE) and calculation of z-scores.

The mitral annular plane systolic excursion (MAPSE) is a quick and reliable echocardiographic tool for assessing longitudinal left ventricular (LV) systolic function in children and adults. Because this parameter is affected by the LV longitudinal dimension, pediatric and adult normal values are not suitable for preterm and term neonates. A prospective study investigated a large group of preterm and term neonates [gestational age (GA), 26/0-6 to 40/0-6; birth weight (BW), 670-4,140 g]. The growth- and BW-related changes in MAPSE were determined to establish normal z-score values for preterm and term neonates. The MAPSE ranged from a mean of 0.36 ± 0.05 cm in preterm neonates with a GA of 26/0-6 to 0.56 ± 0.08 cm in term neonates with a GA of 40/0-6. The findings showed MAPSE, GA, and BW to be moderately correlated. Pearson's correlation coefficient was 0.56 for GA (MAPSE; p < 0.001) and 0.58 for BW (MAPSE; p < 0.001). The normal MAPSE values did not differ significantly between females and males (p = 0.946). The absolute values and z-scores of normal MAPSE values in healthy preterm and term neonates within the first 48 h of life were calculated, and percentile charts were established. Determination of LV function using MAPSE might be useful for vulnerable infants for whom a prolonged examination is inappropriate and for neonates with suboptimal visualization of the endocardium.