Left ventricle shortening fraction: a comparison between euploid and trisomy 21 fetuses in the first trimester.

OBJECTIVES Measurement of the shortening fraction of the left ventricle (SFLV) is an objective way to assess systolic performance. The aim of the study was to compare first trimester SFLV values in euploid fetuses to those in fetuses with trisomy 21. METHODS We measured SFLV in 56 fetuses from 11 weeks to 13 weeks 6 days. The left ventricular diastolic diameter (LVDD) and left ventricular systolic diameter (LVSD) were measured offline, and SFLV was calculated. The data were analyzed using Mann-Whitney U test. RESULTS We found a significant difference in the SFLV measurements between the group of 49 euploid fetuses and the 7 fetuses with trisomy 21 [38.00 (95% CI: 33.72-42.27) vs 49.93 (95% CI: 43.72-56.13)] (p < 0.05). There was also a significant difference in the nuchal translucency measurements between the two groups: 1.78 mm (95% CI: 1.08-2.48 mm) in the euploid population versus 5.06 mm (95% CI: 3.61-6.71 mm) in the fetuses with trisomy 21 (p < 0.05). There were no significant differences between the group of euploid fetuses and the group of trisomy 21 fetuses in the following parameters: CRL (chorionic villus sampling), LVDD and LVSD. CONCLUSIONS SFLV is a well-defined, simple measurement of systolic function of the fetal myocardium. SFLV values in fetuses with trisomy 21 appear to be significantly higher than in euploid fetuses.