Paired maternal and fetal cardiac functional measurements in women with gestational diabetes mellitus at 35-36 weeks' gestation.

BACKGROUND: Gestational diabetes mellitus is associated with early-onset cardiovascular disease and increased incidence of adverse cardiovascular outcomes in mothers and their offspring. Few studies with a limited number of patients have reported subclinical cardiac changes in association with gestational diabetes mellitus; however, it remains unclear whether the mother and the fetus respond in a similar fashion to gestational diabetes mellitus; thus, by assessing the heart of one, we can estimate or predict changes in the other. OBJECTIVE: This study aimed to compare maternal and fetal cardiovascular functions in the third trimester between women with gestational diabetes mellitus and women with uncomplicated pregnancy and to explore whether gestational diabetes mellitus affects to the same extent the maternal and fetal heart. STUDY DESIGN: This was a cross-sectional study of maternal and fetal echocardiography for assessment of cardiovascular function in the third trimester in women with singleton pregnancies who received a diagnosis of gestational diabetes mellitus and the control group with uncomplicated pregnancies. RESULTS: In this study, we included 161 women with gestational diabetes mellitus and 483 women with uncomplicated pregnancies. Compared with women in the control group, women with gestational diabetes mellitus were older (34.5, standard deviation, 5.3 years] vs 32.5, standard deviation, 4.8 years]; P<.001), had higher body mass index (31.3 kg/m2 [standard deviation, 5.8] vs 28.6 kg/m2 [standard deviation, 4.4]; P<.001), had lower weight gain during pregnancy (8.3 [interquartile range, 4.8-11 kg] vs 10.8 [interquartile range, 8.2-13.5 kg]; P<.001), and delivered babies with lower birthweight (P<.001). After multivariable analysis, accounting for differences in maternal characteristics and fetal weight, mothers with gestational diabetes mellitus had lower left ventricular diastolic and systolic (tissue Doppler systolic [s'] wave) functional indices (P<.01 for both) compared with those of mothers in the control group. The noted cardiac changes did not fulfill the adult criteria for clinical cardiac dysfunction. No differences in hemodynamic indices (cardiac output and peripheral vascular resistance) and left ventricular mass were noted between the groups. Fetuses of mothers with gestational diabetes mellitus had more globular-shaped hearts with increased right and left ventricular sphericity indices (P<.001 for both) and reduced global longitudinal right and left ventricular systolic functional indices (P<.001 for both). The effect of gestational diabetes mellitus on maternal and fetal hearts was different, and there was no clear association between the two. CONCLUSION: In the third trimester, in pregnancies with gestational diabetes mellitus, there were subclinical cardiac changes in both the mother and the fetus, but there was no significant difference in any of the fetal cardiac parameters between women with and women without unfavorable cardiac profile. This suggests that the stimulus for cardiovascular responses in the mother and fetus may not be the same in pregnancies with gestational diabetes mellitus.

Fetal Speckle-Tracking: Impact of Angle of Insonation and Frame Rate on Global Longitudinal Strain.

BACKGROUND: There is a growing body of research on fetal speckle-tracking echocardiography because it is considered to be an angle-independent modality. The primary aim of this study was to investigate whether angle of insonation and acquisition frame rate (FR) influence left ventricular endocardial global longitudinal peak strain (GLS) in the fetus. METHODS: Four-chamber views of 122 healthy fetuses were studied at three different angles of insonation (apex up/down, apex oblique, and apex perpendicular) at high and low acoustic FRs. GLS was calculated, and a linear mixed-model analysis was used for analysis. Six hundred fifty-six fetal echocardiographic clips were analyzed (288 in the second trimester, at a median gestation of 21 weeks [interquartile range (IQR), 1 week], and 368 in the third trimester, at a median gestation of 36 weeks [IQR, 2 weeks]). RESULTS: Angle of insonation and FRs were significant determinants of GLS. Ventricular septum perpendicular to the ultrasound beam was associated with higher (more negative) GLS compared with apex up/down (at high FR: -21.8% vs -19.7%, P < .001; at low FR: -24.1% vs -21.4%, P < .001). Higher frames per second (FPS; median 149 FPS [IQR, 33 FPS] = 61 frames per cycle [FPC] [IQR, 17 FPC]) compared with lower FPS (median 51 FPS [IQR, 15 FPS] = 22 FPC [IQR, 7 FPC]) at the same insonation angle resulted in lower GLS (apex up/down: -19.7% vs -21.4%, P < .001; apex oblique: -21.2% vs -22.7%, P < .001; apex perpendicular: -21.8% vs -24.1%, P < .001). CONCLUSIONS: The present findings show that insonation angle and FR influence GLS significantly. These factors need to be considered when comparing studies with different acquisition protocols, when establishing normative values, and when interpreting pathology. Speckle-tracking echocardiography cannot be considered an angle-independent modality during fetal life.