Development of the Z-score for the measurement of myocardial thickness
by means of two-dimensional echocardiography in normal fetuses.
In the current literature, we observed a tendency to describe normal
values of echocardiographic measurements by means of the Z-score. In
fetal cardiology, these Z-score equations are still being established.
Measurement of myocardial thickness is an important assessment
especially in fetuses of diabetic pregnant women because of the risk of
developing myocardial hypertrophy secondary to elevated maternal blood
glucose levels. To determine the percentiles and to develop the Z-score
equations of right and left ventricular lateral wall and
interventricular septum measurements using two-dimensional
echocardiography in normal fetuses between 24 and 34 weeks of gestation.
This is a prospective cross-sectional study that was performed in single
fetuses with normal heart and in non-diabetic pregnant women.
Measurements of the lateral wall of the right and left ventricles and
the interventricular septum were made. 873 pregnant women were included.
We determined the percentiles of the measurements for each gestational
age. The Z-score equation was developed for each of the measurements:
right ventricular lateral wall measurement [RVLW = x - (- 1 + 0.109 *
GI) / 0.4], left ventricle lateral wall measurement [LVLW = x - (-
1.366 + 0.12 * GI) / 0.43] and the interventricular septum in the
four-chamber plane [IVS4ch = (x - (- 1,113+ 0.107 * IG) / 0.4] and
the interventricular septum in the left ventricular outflow tract plane
[IVSLVOT = (x - (-0.581 + 0.084 * GI) / 0.35]. The present study
allowed to demonstrate the percentiles and the Z-score equations for
each of the measures studied.