Allison Divanovic

Prediction and perinatal management of severely restrictive atrial septum in fetuses with critical left heart obstruction: Clinical experience using pulmonary venous Doppler analysis

OBJECTIVE Up to 20% of fetuses with critical left heart obstructive lesions have highly restrictive or intact atrial septae. Although this condition is generally tolerated in utero, severe hypoxemia requiring emergency atrial septostomy often develops in newborns with restrictive atrial septum. We have reported that a pulmonary venous Doppler forward/reverse time-velocity integral ratio less than 5 is highly predictive of the need for emergency atrial septostomy. We reviewed our subsequent experience using fetal pulmonary venous Doppler patterns to identify and manage fetuses with critical left heart obstruction and suspected restrictive atrial septum. METHODS A retrospective review of neonates with a prenatal diagnosis of critical left heart obstruction was performed. Fetal restrictive atrial septum was defined as a small/absent interatrial shunt on 2-dimensional imaging and a mean forward/reverse time-velocity integral ratio of 5 or less. Available serial pulmonary venous Doppler data were reviewed. The primary outcome was postnatal confirmation of restrictive atrial septum or severe left atrial hypertension. RESULTS Eight of 39 infants had a forward/reverse time-velocity integral ratio of 5 or less. A restrictive atrial septum was confirmed postnatally in 6 of 8 infants. Overall, a forward/reverse time-velocity integral ratio of 5 or less had a sensitivity of 100% and specificity of 94% for emergency atrial septostomy. Lowering the cutoff value to 3 or less would have eliminated false-positive diagnoses in the current series. Serial data demonstrated that late second trimester values did not change in later gestation with respect to either threshold in 30 of 32 fetuses. CONCLUSIONS In the fetus with critical left heart obstruction, a threshold forward/reverse time-velocity integral ratio of 3 or less optimizes specificity for predicting emergency atrial septostomy. Most late second trimester values will not change over time with regard to threshold levels.

Estimated cardiac output and cardiovascular profile score in fetuses with high cardiac output lesions

High cardiac output lesions are associated with an increased risk of fetal death, largely as a result of cardiac failure and hydrops fetalis. The cardiovascular profile score (CVPS) has been used to characterize cardiovascular wellbeing, and has been linked to fetal outcomes in other conditions. We aimed to test the hypothesis that elevated combined cardiac output (CCO) in fetuses with high output lesions may be associated with worsening cardiovascular status, as evidenced by a lower CVPS.

Microcephaly is associated with early adverse neurologic outcomes in hypoplastic left heart syndrome

Background:Hypoplastic left heart syndrome (HLHS) is associated with significant mortality and morbidity. Fetal head growth abnormalities have been identified in a subset of HLHS fetuses, but it is unclear whether specific patterns of maladaptive growth affect clinical outcomes. We hypothesized that poor fetal head growth is associated with an increased frequency of adverse clinical outcomes.Methods:We retrospectively examined a cohort of HLHS patients from midgestation to 1 y of age. Fetal and birth anthropometric measurements were analyzed using the Olsen standard, and clinical outcomes were obtained.Results:A total of 104 HLHS patients were identified over a 12-y period; fetal data were available in 38 cases. HLHS neonates demonstrated a high incidence of microcephaly (12%), small head size (27%), and poor head growth (32%). All-cause mortality was 31% at 30 d and 43% at 1 y. Neurologic outcomes were observed in 12% of patients and were significantly increased with microcephaly (43 vs. 4%; P = 0.02). The average length of hospital stay following stage I palliation was 33.4 ± 33 d, correcting for early death.Conclusion:In term nonsyndromic HLHS, fetal and neonatal microcephaly are associated with early adverse neurologic outcomes but not mortality.

Somatic growth trajectory in the fetus with hypoplastic left heart syndrome

Background:Fetal growth abnormalities in hypoplastic left heart syndrome (HLHS) have been documented primarily by birth measurements. Fetal growth trajectory has not been described. We hypothesized that fetal growth trajectory declines across late gestation in this population.Methods:Infants with a prenatal diagnosis of HLHS and no history of prematurity or a genetic syndrome were identified. Fetal ultrasound measurements and birth anthropometrics were obtained from clinical records. z-Scores for estimated fetal weight (EFWz) and birth weight (BWTz) were compared. BWTz for three neonatal standards were compared.Results:Paired fetal and neonatal data were identified in 33 cases of HLHS. Mean gestational age at ultrasound and birth were 27 and 38 wk, respectively. BWTz was lower than EFWz by a mean of 0.82 (SD: 0.72, P < 0.0001), with 64% of subjects demonstrating a decrease in z-score of >0.5. Umbilical artery (UA) Doppler found no evidence of significant placental insufficiency. Modest differences in BWTz were seen across BWT standards in this cohort.Conclusion:The majority of fetuses with HLHS demonstrate decreased growth velocity during later pregnancy, suggesting growth abnormalities manifest in utero. The potential relationship to future clinical outcomes warrants further study.

Assessment of fetal cardiomyopathy in early‐stage twin–twin transfusion syndrome: comparison between commonly reported cardiovascular assessment scores

To assess the relationship between commonly reported fetal cardiomyopathy scoring systems in early‐stage twin–twin transfusion syndrome (TTTS).

Ductus arteriosus aneurysm with massive thrombosis of pulmonary artery and fetal hydrops.

Ductus arteriosus aneurysm (DAA) is a rare cardiovascular lesion usually diagnosed within the first 2 months of life, or less frequently in the 3rd trimester, by antenatal sonography. The true in utero incidence of DAA is unknown, as most affected fetuses are asymptomatic at birth. Potential complications include thromboembolism, rupture, and death. We report a unique lethal case of a large DAA detected by mid–2nd trimester fetal echocardiography, complicated by stricture and massive occlusive thrombosis extending into the pulmonary artery branches. Stricture and thrombosis of the DAA led to interruption of fetal circulation, cardiac failure, and fetal hydrops, ultimately resulting in fetal demise.

Effect of fetal hemodynamics on growth in fetuses with single ventricle or transposition of the great arteries

As birth weight is a critical predictor of outcome in neonates with congenital heart defect (CHD), the common problem of poor fetal growth in this population is clinically important. However, it is not well understood and the impact of fetal hemodynamics on fetal growth and birth weight in those with CHD has not been assessed. In this study, we sought to evaluate the association between combined cardiac output (CCO) and fetal middle cerebral artery (MCA) and umbilical artery (UA) pulsatility indices (PIs) and fetal growth in different subgroups of CHD, and to study the effects of fetal hemodynamics on late gestational weight gain. We hypothesized that fetuses with CHD will have lower CCO and be smaller at birth.

Intrauterine fetal demise after prenatal diagnosis of congenital heart disease: assessment of risk

Elective deliveries in fetal congenital heart disease (CHD) attempt to balance fetal and neonatal risk with the goal of optimizing overall outcome. However, the magnitude of the risk for intrauterine fetal demise (IUFD) is unclear. This study aimed to (1) determine the rate of IUFD and (2) identify fetal risk factors associated with IUFD.

Fetal somatic growth trajectory differs by type of congenital heart disease

BackgroundThe growth trajectories of common measurements, including estimated fetal weight (EFW), head circumference (HC), and abdominal circumference (AC), in fetuses with congenital heart disease (CHD) have not been described for different cardiac lesions. We hypothesized that (i) fetuses with CHD have differential growth in utero, and (ii) different categories of CHD demonstrate different in utero growth curves.MethodsWe performed a retrospective observational cohort study of pregnancies with known fetal CHD seen from January 2000 to June 2013. For analysis, the infants were divided into single ventricle (SV), biventricular conotruncal, d-transposition of great arteries (d-TGA), biventricular septal defects (SD; including atrial, ventricular, and atrioventricular SD), and all others (Other).ResultsA total of 194 newborns met inclusion criteria. There was significant differential growth of EFW in all CHD types, except d-TGA, starting with low z-scores before 25 weeks gestation, improving toward normal around 30–32 weeks gestation, and then again differential growth with advancing gestation. SV and SD groups had significant differential growth of HC starting early in gestation and linearly progressing negative z-scores with advancing gestation.ConclusionWe observed differences in the fetal growth curves throughout gestation for the major categories of CHD, including significant differential growth in even “simple” CHD, such as SD.

First‐Line Antiarrhythmic Transplacental Treatment for Fetal Tachyarrhythmia: A Systematic Review and Meta‐Analysis

Background There is no consensus on the most effective and best tolerated first‐line antiarrhythmic treatment for fetal tachyarrhythmia. The purpose of this systematic review and meta‐analysis was to compare the efficacy, safety, and fetal–maternal tolerance of first‐line monotherapies for fetal supraventricular tachycardia and atrial flutter. Methods and Results A comprehensive search of several databases was conducted through January 2017. Only studies that made a direct comparison between first‐line treatments of fetal tachyarrhythmia were included. Outcomes of interest were termination of fetal tachyarrhythmia, fetal demise, and maternal complications. Ten studies met inclusion criteria, with 537 patients. Overall, 291 patients were treated with digoxin, 137 with flecainide, 102 with sotalol, and 7 with amiodarone. Digoxin achieved a lower rate of supraventricular tachycardia termination compared with flecainide (odds ratio [OR]: 0.773; 95% confidence interval [CI], 0.605–0.987; I2=34%). In fetuses with hydrops fetalis, digoxin had lower rates of tachycardia termination compared with flecainide (OR: 0.412; 95% CI, 0.268–0.632; I2=0%). There was no significant difference in the incidence of maternal side effects between digoxin and flecainide groups (OR: 1.134; 95% CI, 0.129–9.935; I2=80.79%). The incidence of maternal side effects was higher in patients treated with digoxin compared with sotalol (OR: 3.148; 95% CI, 1.468–6.751; I2=0%). There was no difference in fetal demise between flecainide and digoxin (OR: 0.767; 95% CI, 0.140–4.197; I2=44%). Conclusions Flecainide may be more effective treatment than digoxin as a first‐line treatment for fetal supraventricular tachycardia.