Cardiac Function in Fetuses of Poorly-Controlled Pre-Gestational Diabetic Pregnancies – A Pilot Study

Abstract

Objective: Cardiac impairment is frequently found in babies of diabetic mothers. It is still controversial whether this is due to poor glucose control. The aim of this study is to compare the cardiac function in fetuses of well- and poorly-controlled pre-gestational diabetic pregnancy in third trimester. Methods: Women with type 1 pre-gestational diabetes were enrolled at 30–32 weeks. Cardiac size and interventricular septal wall thickness were measured by M-mode at end-diastolic phase. The right and left ventricular ejection fractions were calculated. At the mitral and tricuspid valves inflow, the ratio between early ventricular filling and active atrial filling (E/A) at both atrioventricular valves were measured by Doppler echocardiography. Peak velocities of ascending aorta and pulmonary artery were assessed. The angle of isonation was kept at <20°. Women with poorly-controlled diabetes (HbA1c >6.5%) were compared with those with satisfactorily controlled diabetes (HbA1c ≤6.5%). Results: A total of 21 women with pre-gestational diabetes were recruited for this study. Eight women with well-controlled diabetes were compared with 9 women who had poorly-controlled diabetes. HbA1c in the poorly-controlled group was 7.3% and in the well-controlled group it was 5.4% (p < 0.001). There was no difference between the two groups in cardiac size, interventricular septal wall thickness, ejection fraction, aorta and pulmonary artery peak flow velocities. The right atrioventricular E/A ratio was significantly lower among the poorly-controlled diabetic pregnancies (0.71 vs. 0.54; p < 0.05). Conclusion: Fetuses of poorly-controlled diabetic mothers had a lower right atrioventricular E/A ratio. This may be due to metabolic acidosis, non-hypertrophic cardiac dysfunction or fetal polycythemia.

Increased periconceptual maternal glycated haemoglobin in diabetic mothers reduces fetal long axis cardiac function

“…There were no significant differences in maternal age (non-diabetic mothers 31 (19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)) v diabetic mothers 34 (24-40) years) or parity (1 (0-3)). Two non-diabetic and four diabetic mothers had a previous stillbirth.…”

“…Both systolic and diastolic augmentation of myocardial velocities are seen in FDM suggesting that the hypertrophied ventricle shows adaptation which is not evident from isolated Doppler flow velocities and was interpreted as diastolic dysfunction in previous studies. [24][25][26][27][28][29][30] Although the mechanisms underlying improved cardiac performance in diabetic pregnancies are speculative, the cardiac hypertrophy observed is most likely due to fetal hyperinsulinaemia. Both improved myocardial velocities and hypertrophy are likely to be associated with the increased (but normal) gestational related flow velocities through the pulmonary valve rather than with true outflow tract obstruction, which is easily distinguished by Doppler velocities raised for gestational age and an abnormal waveform.…”

Evaluation of Conventional Doppler Fetal Cardiac Function Parameters: E/A Ratios, Outflow Tracts, and Myocardial Performance Index

“…In uncontrolled diabetic pregnant women, Wong et al [24] also reported a reduction in the E/A ratios, mainly in the right ventricle, reflecting early fetal cardiac adaptation. In fetuses with premature rupture of membranes and microbial invasion of the amniotic cavity, Romero et al [25] showed an increment in E/A velocities and ratios in both cardiac ventricles, also indicating early cardiac dysfunction in these fetuses.…”

Can abnormal ductus venosus peak velocity index for veins in normal fetuses predictfailure of functional closure of the foramen ovale in the postnatal period?

“…In recent years, two of the DV Doppler indices, DV-PVIV and pulsatility index (DV-PI), are being increasingly used in the evaluation of fetal well-being and cardiac hemodynamics. It has been reported that DV indices may be utilized in the assessment of fetal cardiac hemodynamics, as well as in the follow-up of complicated pregnancies (fetal growth restriction, fetal acidemia, twin-to-twin transfusion syndrome, fetal anemia, congenital heart disease, and fetal myocardial hypertrophy) [16][17][18][19][20][21][22].…”