Maternal arterial stiffness and fetal cardiovascular physiology in diabetic pregnancy.

OBJECTIVES: In mothers with pregestational or gestational diabetes, abnormal arterial stiffness (stiffer arteries) has been reported. The impact of abnormal maternal arterial stiffness on placental and fetal cardiovascular physiology is unknown. The purpose of this study was to determine the impact of maternal diabetes on maternal arterial stiffness and the association with fetal cardiovascular physiology as measured by fetal echocardiography. METHODS: Between December 2013 and January 2017 a prospective study was conducted on diabetic (but otherwise healthy) and non-diabetic, healthy pregnant mothers aged 18-40 years at 20-28 weeks' gestation who had a normal fetal cardiac echocardiogram and obstetric ultrasound. Clinical data were collected by means of a patient questionnaire and measurement of blood pressure, height, weight, arterial augmentation index (AIx) and placental and fetal cardiovascular parameters were collected by fetal echocardiography. Descriptive statistics were calculated. Comparisons were made using parametric and non-parametric tests between controls and diabetic mothers. RESULTS: Twenty-three healthy pregnant controls and 43 diabetic pregnant women (22 with pregestational and 21 with gestational diabetes) were included in the study. Maternal AIx was higher in those with diabetes than in healthy controls (12.4 ± 10.6% vs 4.6 ± 7.9%; P = 0.003). Fetal aortic valve (AoV) velocity time integral (VTI) was higher in fetuses whose mothers had diabetes than in those with non-diabetic mothers (7.7 ± 1.9 cm vs 6.3 ± 3.0 cm; P = 0.022). Left ventricular (LV) myocardial performance index (MPI) was lower in diabetic pregnancies than in controls (0.40 ± 0.09 vs 0.46 ± 0.11; P = 0.021). Umbilical artery (UA) resistance index (RI) was lower in diabetic pregnancies with glycated hemoglobin (HbA1c) levels ≥ 6.5% than in those with HbA1c levels < 6.5% (0.69 ± 0.06, n = 15 vs 0.76 ± 0.08, n = 21; P = 0.009) but not at higher HbA1C cut-offs. No correlation between AIx and AoV-VTI, LV-MPI or UA-RI was found. CONCLUSIONS: Arterial stiffness is higher in pregnant women with diabetes than in controls. Fetuses of diabetic mothers show altered cardiovascular parameters, with higher AoV-VTI and lower LV-MPI, which are markers of myocardial function. Placental function assessed by UA-RI was normal despite differences between groups. Arterial stiffness did not correlate with placental or fetal cardiovascular variables. Instead, the findings are likely to represent a shared response to the environment of abnormal glucose metabolism. The clinical significance of these findings is yet to be determined. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Changes in left heart hemodynamics after technically successful in-utero aortic valvuloplasty.

OBJECTIVE: Severe aortic stenosis in the mid-gestation fetus can progress to hypoplastic left heart syndrome (HLHS). @ In-utero aortic valvuloplasty is an innovative therapy to promote left ventricular growth and function and potentially to prevent HLHS. This study evaluated the effects of mid-gestation fetal balloon aortic valvuloplasty on subsequent fetal left ventricular function and left heart Doppler characteristics. METHODS: We reviewed fetuses with aortic stenosis that underwent attempted in-utero aortic valvuloplasty between 2000 and 2006. Pre-intervention and the latest post-intervention fetal echocardiograms were analyzed to characterize changes in left heart function and Doppler characteristics in utero. RESULTS: Forty-two fetuses underwent attempted aortic valvuloplasty during the study period, 12 of which were excluded from analysis secondary to inadequate follow-up data, termination or fetal demise. Study fetuses (n = 30) underwent pre-intervention echocardiography at a median gestational age of 23 weeks, and were followed for a median of 66 +/- 23 days post-intervention. In 26 fetuses, aortic valvuloplasty was technically successful. Among these 26, left heart physiology was abnormal pre-intervention and improved or normalized after intervention in most cases: biphasic mitral inflow was present in 5/25 (20%) cases pre-intervention and in 21/23 (91%) post-intervention (P < 0.001); moderate or severe mitral regurgitation was present in 14/26 (54%) cases pre-intervention and in 5/23 (22%) post-intervention (P = 0.02); bidirectional flow across the patent foramen ovale was present in 0/26 cases pre-intervention and in 6/25 (24%) post-intervention (P = 0.01); antegrade flow in the transverse arch was present in 0/25 cases pre-intervention and in 17/26 (65%) post-intervention (P < 0.001). The left ventricular ejection fraction increased from 19 +/- 10% pre-intervention to 39 +/- 14% post-intervention (P < 0.001). These changes were not observed in control fetuses (n = 18). CONCLUSION: Fetal aortic valvuloplasty, when technically successful, improves left ventricular systolic function and left heart Doppler characteristics.

Bidirectional cavopulmonary anastomosis: impact on diastolic ventricular function indices.

Systolic ventricular function has been demonstrated to remain unchanged following bidirectional cavopulmonary anastomosis (BCPA). The effects of BCPA on diastolic ventricular performance have not been critically assessed. The objective of this study was to evaluate the changes in diastolic ventricular function indices early after BCPA. Nineteen patients were enrolled prospectively. Transthoracic echocardiograms were performed at a median of 4 days prior to and 5 days subsequent to BCPA. Diastolic and systolic echocardiographic indices of ventricular performance were measured for the dominant ventricle. End diastolic volume decreased postoperatively (71.1 +/- 21.1 vs 68.08 +/- 17.9 ml/m2, p = 0.05). Tei index increased postoperatively (0.51 +/- 0.2 vs 0.62 +/- 0.1, p = 0.002), whereas inflow Doppler E velocity (70.3 +/- 13 vs 56.3 +/- 24.7 cm/sec, p = 0.04), E/A ratio (1.18 +/- 0.52 vs 0.84 +/- 0.2, p = 0.02), tissue Doppler E' velocity (9.5 +/- 2.5 vs 6.4 +/- 3.2 cm/sec, p = 0.03) and diastolic flow propagation velocity (56.5 +/- 12 vs 52.8 +/- 11 cm/sec, p = 0.04) all decreased. There was no change in ventricular mass, area change fraction, heart rate, or inflow Doppler A or tissue Doppler A' and S' velocities. This study demonstrated that diastolic indices of ventricular performance are altered indicating decreased diastolic function early following BCPA. Whether this observation is a result of a change in ventricular mass:volume ratio, loading conditions of the ventricle, ventricular geometry, or the effects of cardiopulmonary bypass remains to be determined.