Determinants of outcome in fetal pulmonary valve stenosis or atresia with intact ventricular septum

Echocardiographic characteristics and clinical outcomes in fetuses with pulmonary stenosis or pulmonary atresia with intact ventricular septum

OBJECTIVE

To summarize echocardiographic characteristics of the anatomy and hemodynamic and clinical outcomes in fetuses with isolated pulmonary stenosis (PS) or pulmonary atresia with intact ventricular septum (PA/IVS).

METHODS

This was a single-center retrospective study of fetuses with isolated PS or PA/IVS. Echocardiographic variables and clinical outcomes after delivery were evaluated and compared.

RESULTS

Between 2016 and 2021, 115 livebirths with isolated PS or PA/IVS were included. Proportion of fetuses with mild, moderate and critical PS and PA/IVS was 41.7 %, 18.3 %, 26.1 % and 13.9 %. Fetuses with more severe PS had worse anatomic and hemodynamic profiles. Specifically, the cardiothoracic ratio, pulmonary valve (PV) velocity, degree and velocity of tricuspid regurgitation increased as PS severity increased; and the pulmonary artery/aorta ratio, right ventricle/left ventricle long-axis (TV/MV) ratio, tricuspid valve/mitral valve annulus (TV/MV) ratio, and tricuspid valve inflow duration/cardiac cycle ratio decreased as PS severity increased (P <0.001 for all). PV velocity ≥2 m/s predicted PV pressure ≥40 mm Hg after delivery, with an AUC of 0.81; TV/MV ratio combined with RV/LV ratio predicted clinical outcomes, with an AUC of 0.88. Live births with more severe PS had higher mortality rate (mild 0 vs. moderate 0 vs. critical 11 % vs. PA-IVS 36 %) and lower rate of developing bi-ventricles (mild 100 % vs. moderate 95 % vs. critical 89 % vs. PA-IVS 36 %).

CONCLUSION

Findings of this study help better understand the anatomy and hemodynamic and clinical outcomes in fetuses with isolated PS or PA/IVS, which could have implications for prenatal counseling and prediction of fetal outcome.

Prediction of postnatal circulation in pulmonary atresia/critical stenosis with intact ventricular septum: systematic review and external validation of models

OBJECTIVE

A favorable postnatal prognosis in cases of pulmonary atresia/critical stenosis with intact ventricular septum (PA/CS-IVS) is generally equated with the possibility of achieving biventricular (BV) repair. Identification of fetuses that will have postnatal univentricular (UV) circulation is key for prenatal counseling, optimization of perinatal care and decision-making regarding fetal therapy. We aimed to evaluate the accuracy of published models for predicting postnatal circulation in PA/CS-IVS using a large internationally derived validation cohort.

METHODS

This was a systematic review of published uni- and multiparametric models for the prediction of postnatal circulation based on echocardiographic findings at between 20 and 28 weeks of gestation. Models were externally validated using data from the International Fetal Cardiac Intervention Registry. Sensitivity, specificity, predictive values, area under the receiver-operating-characteristics curves (AUCs) and proportion of cases with true vs predicted outcome were calculated.

RESULTS

Eleven published studies that reported prognostic parameters of postnatal circulation were identified. Models varied widely in terms of the main outcome (UV (n = 3), non-BV (n = 3), BV (n = 3), right-ventricle-dependent coronary circulation (n = 1) or tricuspid valve size at birth (n = 1)) and in terms of the included predictors (single parameters only (n = 6), multiparametric score (n = 4) or both (n = 1)), and were developed on small sample sizes (range, 15-38). Nine models were validated externally given the availability of the required parameters in the validation cohort. Tricuspid valve diameter Z-score, tricuspid regurgitation, ratios between right and left cardiac structures and the presence of ventriculocoronary connections (VCC) were the most commonly evaluated parameters. Multiparametric models including up to four variables (ratios between right and left structures, right ventricular inflow duration, presence of VCC and tricuspid regurgitation) had the best performance (AUC, 0.80-0.89). Overall, the risk of UV outcome was underestimated and that of BV outcome was overestimated by most models.

CONCLUSIONS

Current prenatal models for the prediction of postnatal outcome in PA/CS-IVS are heterogeneous. Multiparametric models for predicting UV and non-BV circulation perform well in identifying BV patients but have low sensitivity, underestimating the rate of fetuses that will ultimately have UV circulation. Until better discrimination can be achieved, fetal interventions may need to be limited to only those cases in which non-BV postnatal circulation is certain. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Fetal cardiac interventions: First-year experience of a tertiary referral center in Turkey

AIM

To present the first-year experience of fetal cardiac interventions (FCIs) in a tertiary referral hospital and to evaluate the outcomes.

METHODS

This retrospective study consisted of four pregnant women who underwent fetal pulmonary or aortic balloon valvuloplasty between November 2020 and June 2021. The procedures were performed with a percutaneous cardiac puncture under the ultrasonography guidance. Gestational age at intervention, procedural success, complications, and perinatal outcomes were evaluated. Procedural complications defined as fetal bradyarrhythmia requiring treatment, pericardial effusion requiring drainage, balloon rupture, and fetal death. The procedure was considered technically successful if the valve was dilated with a balloon catheter. Ultimately successful procedure was defined as the discharge of infants alive with biventricular circulation.

RESULTS

A total of 5 FCIs attempted between 26 + 3 and 28 + 2 gestational weeks. While the procedure was technically successful in 2 cases with pulmonary stenosis, both attempts were unsuccessful in the fetus with pulmonary atresia. Although the procedure was technically successful in the patient with critical aortic stenosis, it ultimately failed. No fetal death occurred in our series and there were no procedure-related significant maternal complications. However, three interventions were complicated by fetal bradycardia and pericardial effusion necessitating treatment, and balloon rupture cropped up in one case.

CONCLUSION

FCIs may lead to improving the likelihood of a biventricular outcome for selected fetuses. Careful selection of patients and centralization of experience are essential for obtaining favorable outcomes. Operators should be aware of procedural complications. Improved procedural techniques with a lower complication rate will be achieved through advanced medical technology and special balloon catheters.

Prenatal Diagnosis of Fetal Heart Failure

Fetal heart failure (FHF) is a condition of inability of the fetal heart to deliver adequate blood flow for tissue perfusion in various organs, especially the brain, heart, liver and kidneys. FHF is associated with inadequate cardiac output, which is commonly encountered as the final outcome of several disorders and may lead to intrauterine fetal death or severe morbidity. Fetal echocardiography plays an important role in diagnosis of FHF as well as of the underlying causes. The main findings supporting the diagnosis of FHF include various signs of cardiac dysfunction, such as cardiomegaly, poor contractility, low cardiac output, increased central venous pressures, hydropic signs, and the findings of specific underlying disorders. This review will present a summary of the pathophysiology of fetal cardiac failure and practical points in fetal echocardiography for diagnosis of FHF, focusing on essential diagnostic techniques used in daily practice for evaluation of fetal cardiac function, such as myocardial performance index, arterial and systemic venous Doppler waveforms, shortening fraction, and cardiovascular profile score (CVPs), a combination of five echocardiographic markers indicative of fetal cardiovascular health. The common causes of FHF are reviewed and updated in detail, including fetal dysrhythmia, fetal anemia (e.g., alpha-thalassemia, parvovirus B19 infection, and twin anemia-polycythemia sequence), non-anemic volume load (e.g., twin-to-twin transfusion, arteriovenous malformations, and sacrococcygeal teratoma, etc.), increased afterload (intrauterine growth restriction and outflow tract obstruction, such as critical aortic stenosis), intrinsic myocardial disease (cardiomyopathies), congenital heart defects (Ebstein anomaly, hypoplastic heart, pulmonary stenosis with intact interventricular septum, etc.) and external cardiac compression. Understanding the pathophysiology and clinical courses of various etiologies of FHF can help physicians make prenatal diagnoses and serve as a guide for counseling, surveillance and management.

Right ventricular outflow tract anomalies: Neonatal interventions and outcomes

Right ventricular outflow tract (RVOT) anomalies comprise a wide spectrum of congenital heart disease, typically characterized by obstruction to flow from the right ventricle to pulmonary arteries. This review highlights important considerations surrounding management strategy as well as clinical outcomes for the neonate with RVOT anomaly, including: pulmonary atresia with intact ventricular septum, congenital pulmonary valve stenosis, tetralogy of Fallot, and Ebstein anomaly with anatomic or physiologic RVOT obstruction.

A 'holistic' sonographic view on congenital heart disease - How automatic reconstruction using fetal intelligent navigation echocardiography (FINE) eases the unveiling of abnormal cardiac anatomy part I: Right heart anomalies

Attempting a comprehensive examination of the fetal heart remains challenging for unexperienced operators as it emphasizes the acquisition and documentation of sequential cross-sectional and sagittal views and inevitably results in diminished detection rates of fetuses affected by congenital heart disease. The introduction of four-dimensional spatio-temporal image correlation (4D STIC) technology facilitated a volumetric approach for thorough cardiac anatomic evaluation by the acquisition of cardiac 4D datasets. By analyzing and re-arranging of numerous frames according to their temporal event within the heart cycle, STIC allows visualization of cardiac structures as an endless cine loop sequence of a complete single cardiac cycle in motion. However, post-analysis with manipulation and repeated slicing of the volume usually requires experience and in-depth anatomic knowledge, which limits the widespread application of this advanced technique in clinical care and unfortunately leads to the underestimation of its diagnostic value to date. Fetal intelligent navigation echocardiography (FINE), a novel method that automatically generates and displays nine standard fetal echocardiographic views in normal hearts, has shown to be able to overcome these limitations. Very recent data on the detection of congenital heart defects (CHDs) using the FINE method revealed a high sensitivity and specificity of 98% and 93%, respectively. In this two-part manuscript, we focused on the performance of FINE in delineating abnormal anatomy of typical right and left heart lesions and thereby emphasized the educational potential of this technology for more than just teaching purposes. We further discussed recent findings in a pathophysiological and/or functional context.

Fetal cardiac filling and ejection time fractions by pulsed-wave Doppler: reference ranges and potential clinical application

OBJECTIVES

Fetal cardiac function can be evaluated using a variety of parameters. Among these, cardiac cycle time-related parameters, such as filling time fraction (FTF) and ejection time fraction (ETF), are promising but rarely studied. We aimed to report the feasibility and reproducibility of fetal FTF and ETF measurements using pulsed-wave Doppler, to provide reference ranges for fetal FTF and ETF, after evaluating their relationship with heart rate (HR), gestational age (GA) and estimated fetal weight (EFW), and to evaluate their potential clinical utility in selected fetal conditions.

METHODS

This study included a low-risk prospective cohort of singleton pregnancies and a high-risk population of fetuses with severe twin-twin transfusion syndrome (TTTS), aortic stenosis (AoS) or aortic coarctation (CoA), from 18 to 41 weeks' gestation. Left ventricular (LV) and right ventricular inflow and outflow pulsed-wave Doppler signals were analyzed, using valve clicks as landmarks. FTF was calculated as: (filling time/cycle time) × 100. ETF was calculated as: (ejection time/cycle time) × 100. Intraclass correlation coefficients (ICC) were used to evaluate the intra- and interobserver reproducibility of FTF and ETF measurements in low-risk fetuses. The relationships of FTF and ETF with HR, GA and EFW were evaluated using multivariate regression analysis. Reference ranges for FTF and ETF were then constructed using the low-risk population. Z-scores of FTF and ETF in the high-risk fetuses were calculated and analyzed.

RESULTS

In total, 602 low-risk singleton pregnancies and 54 high-risk fetuses (nine pairs of monochorionic twins with severe TTTS, 16 fetuses with AoS and 20 fetuses with CoA) were included. Adequate Doppler traces for FTF and ETF could be obtained in 95% of low-risk cases. Intraobserver reproducibility was good to excellent (ICC, 0.831-0.905) and interobserver reproducibility was good (ICC, 0.801-0.837) for measurements of all timing parameters analyzed. Multivariate analysis of FTF and ETF in relation to HR, GA and EFW in low-risk fetuses identified HR as the only variable predictive of FTF, while ETF was dependent on both HR and GA. FTF increased with decreasing HR in low-risk fetuses, while ETF showed the opposite behavior, decreasing with decreasing HR. Most recipient twins with severe TTTS showed reduced FTF and preserved ETF. AoS was associated with decreased FTF and increased ETF in the LV, with seemingly different patterns associated with univentricular vs biventricular postnatal outcome. The majority of fetuses with CoA had FTF and ETF within the normal range in both ventricles.

CONCLUSIONS

Measurement of FTF and ETF using pulsed-wave Doppler is feasible and reproducible in the fetus. The presented reference ranges account for associations of FTF with HR and of ETF with HR and GA. These time fractions are potentially useful for clinical monitoring of cardiac function in severe TTTS, AoS and other fetal conditions overloading the heart. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Natural history of pulmonary atresia with intact ventricular septum (PAIVS) and critical pulmonary stenosis (CPS) and prediction of outcome

Objectives

To analyse prenatal parameters predicting biventricular (BV) outcome in pulmonary atresia with intact ventricular septum/critical pulmonary stenosis (PAIVS/CPS).

Methods

We evaluated 82 foetuses from 01/08 to 10/18 in 3 centres in intervals 1 (< 24 weeks), 2 (24–30 weeks) and 3 (> 30 weeks).

Results

61/82 (74.4%) were livebirths, 5 (8.2%) lost for follow-up, 3 (4.9%) had compassionate care leaving 53 (64.6% of the whole cohort and 86.9% of livebirths) with intention to treat. 9 died, 44/53 (83.0%) survived. 24/38 (63.2%) with information on postnatal outcome had BV outcome, 14 (36.8%) non-BV outcome (2 × 1.5 circulation). One with BV outcome had prenatal valvuloplasty. Best single parameter for BV outcome was tricuspid/mitral valve (TV/MV) ratio (AUC 0.93) in intervals 2 and 3 (AUC 0.92). Ventriculo-coronary-arterial communications (VCAC) were present in 11 (78.6%) in non-BV outcome group vs. 2 (8.3%) in BV outcome group (p < 0.001). Tricuspid insufficiency (TI)-Vmax > 2.5 m/s was present in BV outcome group in75.0% (18/24) vs. 14.3% (2/14) in non-BV outcome group. Including the most predictive markers (VCAC presence, TI- Vmax  < 2.5 m/s, TV/MV ratio < cutoff) to a score, non-BV outcome was correctly predicted when > 1 criterion was fulfilled in all cases. After recently published criteria for foetal intervention, only 4/9 (44.4%) and 5/14 (35.7%) in our interval 2 + 3 with predicted non-BV outcome would have been candidates for intervention. Two (1 × intrauterine intervention) in interval 2, two in interval 3 reached BV outcome and one 1.5 circulation without intervention.

Conclusion

TV/MV ratio as simple parameter has high predictive value. After our score, non-BV outcome was correctly predicted in all cases. Criteria for foetal intervention must further be evaluated.

Fetal Pulmonary Valvuloplasty in Fetuses with Right Ventricular Outflow Tract Obstructive Disease: Experience and Outcome of the First Five Cases in China

The current study was to report our initial experiences of fetal pulmonary valvuloplasty (FPV) for fetuses with pulmonary atresia with intact ventricular septum (PA/IVS) and critical pulmonary stenosis (CPS), including case selection, technical feasibility, and the effects of FPV on utero and postnatal outcome. Two fetuses with PA/IVS and three fetuses with CPS were enrolled between September 2016 and April 2018. All fetuses were with concomitant severe right ventricular dysplasia and growth arrest. Parameters of right cardiac development and hemodynamics, including tricuspid/mitral annulus ratio (TV/MV), right ventricle/left ventricle long-axis ratio (RV/LV), tricuspid valve inflow duration/cardiac cycle ratio (TVI/CC), degree of tricuspid regurgitation (TR), and blood flow direction of arterial duct and ductus venosus, were evaluated using echocardiogram. FPV was performed trans-abdominally under ultrasound guidance. Echocardiogram was performed post-FPV and every 2-4 weeks thereafter until delivery. The median gestational age at the time of FPV was 28 weeks. From technical perspective, pulmonary balloon valvuloplasty was successfully performed and the opening of pulmonary valve was improved in all fetuses in 2-4 weeks. However, progressive restenosis was observed in four fetuses with gestation advancing, and re-atresia occurred in two PA/IVS fetuses at 36th and 37th weeks' gestation, respectively. The growth trajectories of TV/MV, RV/LV, and TVI/CC were improved in the 1st week after FPV and then slowed down along with pulmonary valve restenosis. All fetuses were born alive and underwent postnatal interventions, including pulmonary balloon valvuloplasty in three fetuses and surgical procedures in two fetuses. During follow-up, three fetuses turned to be biventricular, one became one and a half ventricular at 1-year old, and one died of neonatal infection. Although pulmonary valve restenosis might occur as gestation advancing, FPV seems to be a safe and feasible procedure to improve the growth trajectories of right heart for fetuses with PA/IVS and CPS.

Fetal Cardiac Intervention for Pulmonary Atresia with Intact Ventricular Septum: International Fetal Cardiac Intervention Registry

INTRODUCTION

Invasive fetal cardiac intervention (FCI) for pulmonary atresia with intact ventricular septum (PAIVS) and critical pulmonary stenosis (PS) has been performed with small single-institution series reporting technical and physiological success. We present the first multicenter experience.

OBJECTIVES

Describe fetal and maternal characteristics of those being evaluated for FCI, including pregnancy/neonatal outcome data using the International Fetal Cardiac Intervention Registry (IFCIR).

METHODS

We queried the IFCIR for PAIVS/PS cases evaluated from January 2001 to April 2018 and reviewed maternal/fetal characteristics, procedural details, pregnancy and neonatal outcomes. Data were analyzed using standard descriptive statistics.

RESULTS

Of the 84 maternal/fetal dyads in the registry, 58 underwent pulmonary valvuloplasty at a median gestational age of 26.1 (21.9-31.0) weeks. Characteristics of fetuses undergoing FCI varied in terms of tricuspid valve (TV) size, TV regurgitation, and pulmonary valve patency. There were fetal complications in 55% of cases, including 7 deaths and 2 delayed fetal losses. Among those who underwent successful FCI, the absolute measurement of the TV increased by 0.32 (±0.17) mm/week from intervention to birth. Among 60 liveborn with known outcome, there was a higher percentage having a biventricular circulation following successful FCI (87 vs. 43%).

CONCLUSIONS

Our data suggest a possible benefit to fetal therapy for PAIVS/PS, though rates of technically unsuccessful procedures and procedure-related complications, including fetal loss were substantial. FCI criteria are extremely variable, making direct comparison to nonintervention patients challenging and potentially biased. More uniform FCI criteria for fetuses with PAIVS/PS are needed to avoid unnecessary procedures, expose only fetuses most likely to sustain a benefit, and to enable comparisons to be made with nonintervention patients.

An Overview of Contemporary Outcomes in Fetal Cardiac Intervention: A Case for High-Volume Superspecialization?

Fetal cardiac interventions (FCI) offer the opportunity to rescue a fetus at risk of intrauterine death, or more ambitiously to alter disease progression. Most of these fetuses require multiple additional postnatal procedures, and it is difficult to disentangle the effect of the fetal procedure from that of the postnatal management sequence. The true clinical impact of FCI may only be discernible in large-volume institutions that can commit to a standardized postnatal approach and have sufficient case volume to overcome their FCI learning curve.

Fetal cardiac interventions: Where do we stand?

Fetal cardiac intervention (FCI) is a novel and evolving technique that allows for in utero treatment of a subset of congenital heart disease. This review describes the rationale, selection criteria, technical features, and current outcomes for the three most commonly performed FCI: fetal aortic stenosis with evolving hypoplastic left heart syndrome (HLHS); HLHS with intact or restrictive atrial septum; and pulmonary atresia with intact ventricular septum, with concern for worsening right ventricular (RV) hypoplasia.

Severe Pulmonary Stenosis or Atresia with Intact Ventricular Septum in the Fetus: The Natural History

PURPOSE

To assess the intrauterine course, the outcome, and to establish a new prenatal echocardiographic scoring system to predict biventricular (BV) versus univentricular (UV) outcome of fetuses with severe pulmonary stenosis or atresia with intact ventricular septum (PSAIVS).

METHODS

All cases of PSAIVS diagnosed prenatally over a period of 14years were retrospectively collected in 2 tertiary referral centers.

RESULTS

Forty-nine fetuses with PSIVS (n = 11) or PAIVS (n = 38) were identified prenatally. Nineteen (38.8%) fetuses had additional ventriculocoronary connections (VCCs) and 21 (42.9%) fetuses had right ventricular hypoplasia. Four (8.2%) pregnancies were terminated, 2 (4.1%) ended in intrauterine fetal death, 4 (8.2%) in neonatal death, and 5 (10.2%) children died in infancy or childhood, including one case with compassionate care. Thirty-four of 44 (77.3%) fetuses with the intention-to-treat were alive at latest follow-up, 25 (73.5%) with BV, and 9 (26.5%) with UV circulation. Most significant predictive markers of UV circulation were Vmax of tricuspid regurgitation (TR) <2 m/s, right ventricle/left ventricle length ratio ≤0.6, and presence of VCC. A scoring system including these 3 markers had 100% sensitivity and 100% specificity predicting an UV outcome if more than one of these criteria was fulfilled. All 25 liveborn infants that were suitable for BV repair survived, whereas only 9 out of 14 candidates for UV repair survived. None of the 14 fetuses with predicted UV outcome would have met the inclusion criteria for fetal intervention, as 10 of them had VCC and the remaining 4 had absent TR or Vmax <2 m/s.

CONCLUSION

The prognosis of prenatally diagnosed PSAIVS is good if BV circulation can be achieved, while postnatal mortality in UV circulation is high within the first 4 months of life. Postnatal outcome can be predicted prenatally with high accuracy using a simple scoring system. This information is mandatory for parental counseling and may be useful in selecting fetuses for intrauterine valvuloplasty.

Reference Ranges for the Size of the Fetal Cardiac Outflow Tracts From 13 to 36 Weeks Gestation: A Single-Center Study of Over 7000 Cases

BACKGROUND

Assessment of the outflow tract views is an integral part of routine fetal cardiac scanning. For some congenital heart defects, notably coarctation of the aorta, pulmonary valve stenosis, and aortic valve stenosis, the size of vessels is important both for diagnosis and prognosis. Existing reference ranges of fetal outflow tracts are derived from a small number of cases.

METHODS AND RESULTS

The study population comprised 7945 fetuses at 13 to 36 weeks' gestation with no detectable abnormalities from pregnancies resulting in normal live births. Prospective measurements were taken of (1) the aortic and pulmonary valves in diastole at the largest diameter with the valve closed, (2) the distal transverse aortic arch on the 3 vessel and trachea view beyond the trachea at the distal point at its widest systolic diameter, and (3) the arterial duct on the 3 vessel and trachea view at its widest systolic diameter. Regression analysis, with polynomial terms to assess for linear and nonlinear contributors, was used to establish the relationship between each measurement and gestational age. The measurement for each cardiac diameter was expressed as a z score (difference between observed and expected value divided by the fitted SD corrected for gestational age) and percentile. Analysis included calculation of gestation-specific SDs. Regression equations are provided for the cardiac outflow tracts and for the distal transverse aortic arch:arterial duct ratio.

CONCLUSIONS

The study established reference ranges for fetal outflow tract measurements at 13 to 36 weeks' gestation that are useful in clinical practice.

Fetal Echocardiographic Parameters and Surgical Outcomes in Congenital Left-Sided Cardiac Lesions

This study aimed to evaluate fetal echocardiographic parameters associated with neonatal intervention and single-ventricle palliation (SVP) in fetuses with suspected left-sided cardiac lesions. Initial fetal echocardiograms (1/2002-1/2017) were interpreted by the contemporary fetal cardiologist as coarctation of the aorta (COA), left heart hypoplasia (LHH), hypoplastic left heart syndrome (HLHS), mitral valve hypoplasia (MVH) ± stenosis, and aortic valve hypoplasia ± stenosis (AS). The cohort comprised 68 fetuses with suspected left-sided cardiac lesions (COA n = 15, LHH n = 9, HLHS n = 39, MVH n = 1, and AS n = 4). Smaller left ventricular (LV) length Z score, aortic valve Z score, ascending aorta Z score, and aorta/pulmonary artery ratio; left-to-right shunting at the foramen ovale; and retrograde flow in the aortic arch were associated with the need for neonatal intervention (p = 0.005-0.04). Smaller mitral valve (MV) Z score, LV length Z score, aortic valve Z score, ascending aorta Z score, aorta/pulmonary artery ratio, and LV ejection fraction, as well as higher tricuspid valve-to-MV (TV/MV) ratio, right ventricular-to-LV (RV/LV) length ratio, left-to-right shunting at the foramen ovale, abnormal pulmonary vein Doppler, absence of prograde aortic flow, and retrograde flow in the aortic arch were associated with SVP (p < 0.001-0.008). The strongest independent variable associated with SVP was RV/LV length ratio (stepwise logistical regression, p = 0.03); an RV/LV length ratio > 1.28 was associated with SVP with a sensitivity of 76% and specificity of 96% (AUC 0.90, p < 0.001). A fetal RV/LV length ratio of > 1.28 may be a useful threshold for identifying fetuses requiring SVP.

Myocardial strain abnormalities in fetuses with pulmonary atresia and intact ventricular septum

OBJECTIVES

Global and regional myocardial deformation have not been well described in fetuses with pulmonary atresia and intact ventricular septum (PA/IVS). Speckle-tracking echocardiography (STE), an angle-independent technique for assessing global and regional strain, may be a more sensitive way of determining ventricular systolic dysfunction compared with traditional 2D echocardiography. The aim of this study was to assess myocardial deformation in fetuses with PA/IVS compared with control fetuses and to determine if, in fetuses with PA/IVS, strain differs between those with and those without right ventricle-dependent coronary circulation (RVDCC).

METHODS

This was a retrospective analysis of fetuses with PA/IVS examined at two medical centers between June 2005 and October 2017. Left ventricular (LV) and right ventricular (RV) regional and global longitudinal strain (GLS) and strain rate were obtained using STE, and comparisons were made between fetuses with PA/IVS and gestational age (GA)-matched controls. Postnatal outcome was assessed, including the presence of RVDCC.

RESULTS

Fifty-seven fetuses with PA/IVS and 57 controls were analyzed at a mean GA of 26.5 ± 5 weeks. LV-GLS was significantly decreased in fetuses with PA/IVS compared with controls (-17.4 ± 1.7% vs -23.7 ± 2.0%, P < 0.001). LV strain rate was also significantly decreased (-1.01 ± 0.21/s vs -1.42 ± 0.20/s, P < 0.001). Fetuses with PA/IVS had decreased strain in all segments. Similarly, RV strain was significantly decreased in fetuses with PA/IVS (-11.6 ± 3.8% vs -24.6 ± 2.5%, P < 0.0001). Thirty-six patients had postnatal cardiac catheterization performed to define coronary anatomy; 10 fetuses had RVDCC. Fetuses with RVDCC had decreased LV strain compared with those without (-15.8 ± 1.2% vs -17.9 ± 1.7%, P = 0.009). RV strain was also decreased in fetuses with RVDCC vs those without (-7.0 ± 2.9% vs -12.1 ± 3.2%, P = 0.0004).

CONCLUSIONS

Fetuses with PA/IVS have decreased global and regional LV and RV strain compared with controls. The finding of decreased LV strain may be due to altered ventricular mechanics in the context of a hypertensive right ventricle and/or abnormal coronary perfusion. Moreover, fetuses that were found to have RVDCC postnatally had decreased LV and RV strain compared with those that did not. These results encourage further investigation to assess whether fetal ventricular strain could be a prenatal predictor of RVDCC. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Fetal cardiac intervention for right sided heart disease: Pulmonary atresia with intact ventricular septum

Congenital heart disease (CHD), the most common of birth defects, can be serious enough to require a lifetime of medical care including multiple surgeries or other interventions. Advances in ultrasound technology and a better understanding of the progression of CHDs have made it possible to intervene in utero. This early stage intervention allows the still plastic cardiovascular system to return to a more normal trajectory thus sparing the newborn from negative consequences to morbidity and mortality. Fetal cardiac intervention (FCI) has been successful for the alleviation of left ventricular dysfunction resulting in remarkably positive outcomes for many families. Promising results support that FCI may also be useful in alleviating right ventricular dysfunction. This bodes well for expanding the use of FCI to lead to better postnatal adaptation and improved long-term function for more children with CHD.

In utero intervention for severe congenital heart disease

The aim of foetal cardiac therapy is to treat an abnormality at the developmental stage so that the process of cardiac growth, which is complex and relies on the volume and direction of circulating blood as well as genetic determinants, can continue. In reality, most cardiac interventions are palliative; hence, major abnormalities are still present at birth. Nevertheless, tangible benefits following successful foetal intervention include improved haemodynamics and reduction in secondary damage leading to better postnatal outcomes. In cases of semilunar valve stenosis, or atresia, foetal valvuloplasty aims to achieve a biventricular, rather than univentricular, circulation. Opening and stenting a restrictive atrial foramen may preserve the pulmonary function in cases of hypoplastic left heart syndrome, thereby increasing the chances of successful postnatal surgery. More recent endeavours include percutaneous implantation of a miniaturised pacemaker to treat complete heart block and the promotion of left-sided heart growth by chronic maternal hyperoxygenation. The true clinical benefit of these interventions over natural history remains uncertain because of the paucity of appropriate randomised controlled trials (RCTs). Foetal cardiac therapy must now move from a pioneering approach to one that is supported by evidence, as has been done successfully for other foetal therapies.

Controversy About a High-Risk and Innovative Fetal Cardiac Intervention

A 20-week-old fetus was diagnosed with critical pulmonary valve stenosis. Given the ultrasound findings, the outcome was difficult to predict. The fetal cardiologists discussed the possibility of a pulmonary valvuloplasty (an experimental procedure) with the parents, wherein the fetal right ventricle would be punctured with a long 18G needle, and through it, a wire advanced across the pulmonary valve, allowing for balloon dilation of the valve. The experimental procedure had been performed at a handful of centers. There were some reports of success. The parents sought an opinion at one of the referral centers that had tried the procedure. The doctors there recommended against it. The doctors at the original center were unsure whether they should try the procedure. The parents wanted it. In this ethics rounds, doctors and the parents discuss the arguments for and against a high-risk, innovative in utero procedure.

Immediate effects and outcome of in-utero pulmonary valvuloplasty in fetuses with pulmonary atresia with intact ventricular septum or critical pulmonary stenosis

OBJECTIVE

To assess the immediate effects of fetal pulmonary valvuloplasty on right ventricular (RV) size and function as well as in-utero RV growth and postnatal outcome.

METHODS

Patients with pulmonary atresia with intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS) who underwent fetal pulmonary valvuloplasty at our center between October 2000 and July 2017 were included. Echocardiographic data obtained before and after the procedure were analyzed retrospectively (median interval after intervention, 1 (range, 1-3) days) for ventricular and valvular dimensions and ratios, RV filling time (duration of tricuspid valve (TV) inflow/cardiac cycle length), TV velocity time integral (TV-VTI) × heart rate (HR) and tricuspid regurgitation (TR) velocity. Longitudinal data were collected from only those fetuses followed up in our center. Outcome was assessed using the scoring system as described by Roman et al. for non-biventricular outcome.

RESULTS

Thirty-five pulmonary valvuloplasties were performed in our institution on 23 fetuses with PAIVS (n = 15) or CPS (n = 8). Median gestational age at intervention was 28 + 4 (range, 23 + 6 to 32 + 1) weeks. No fetal death occurred. Immediately after successful intervention, RV/left ventricular length (RV/LV) ratio (P ≤ 0.0001), TV/mitral valve annular diameter (TV/MV) ratio (P ≤ 0.001), RV filling time (P ≤ 0.00001) and TV-VTI × HR (P ≤ 0.001) increased significantly and TR velocity (P ≤ 0.001) decreased significantly. In fetuses followed longitudinally to delivery (n = 5), RV/LV and TV/MV ratios improved further or remained constant until birth. Fetuses with unsuccessful intervention (n = 2) became univentricular, all others had either a biventricular (n = 15), one-and-a-half ventricular (n = 3) or still undetermined (n = 3) outcome. Five of nine fetuses with a predicted non-biventricular outcome, in which the procedure was successful, became biventricular, while two of nine had an undetermined circulation.

CONCLUSION

In selected fetuses with PAIVS or CPS, in-utero pulmonary valvuloplasty led immediately to larger RV caused by reduced afterload and increased filling, thus improving the likelihood of biventricular outcome even in fetuses with a predicted non-biventricular circulation. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Biventricular impact of mild to moderate fetal pulmonary valve stenosis

OBJECTIVES

To define the pattern of fetal echocardiographic changes associated with isolated pulmonary valve stenosis (PS) and to correlate the echocardiographic findings with neonatal outcome and the need for postnatal pulmonary valvuloplasty within the first 12 months postpartum.

METHODS

This was a prospective cohort study between January 2009 and October 2015 of 16 fetuses with isolated PS and 48 controls matched by gestational age at ultrasound examination (± 2 weeks) evaluated at the Fetal Cardiology Unit at BCNatal (Barcelona). Standard fetal ultrasound and comprehensive echocardiography, which included cardiovascular morphometric parameters, and systolic and diastolic functional and timing measurements, were performed in all cases. Baseline characteristics and perinatal outcome were retrieved from clinical records. Cases were followed up until 12 months of age, and admission to intensive care unit, days of hospitalization, need for prostaglandins and requirement for postnatal surgery were reviewed. Fetal PS cases were analyzed according to the need for postnatal pulmonary valvuloplasty.

RESULTS

The study groups were similar in terms of baseline, fetal ultrasound and perinatal characteristics. Median gestational age at diagnosis of PS was 33.4 (range, 20.0-36.5) weeks. Most cases corresponded to mild or moderate PS; only three fetuses had reversed flow in the ductus arteriosus before delivery. Six (37.5%) newborns, including all three with reversed flow in the ductus arteriosus prenatally, required postnatal pulmonary valvuloplasty. Fetuses with PS presented with larger and more globular hearts, with increased myocardial wall thickness in the third trimester. Despite preserved right ventricular (RV) ejection fraction and systolic longitudinal motion, PS cases showed increased right cardiac output and signs of diastolic dysfunction, with higher ductus venosus pulsatility index (0.72 ± 0.32 vs 0.53 ± 0.16, P = 0.004) and tricuspid E/E' ratio (7.52 ± 3.07 vs 5.76 ± 1.79, P = 0.022). In addition, fetuses with PS displayed a compensatory increase in left ventricular (LV) radial and longitudinal motion, as shown by a higher ejection fraction (79.3 ± 8.23% vs 67.6 ± 11.3%, P = 0.003) and mitral annular-plane systolic excursion (5.94 ± 1.38 vs 5.0 ± 1.22 mm, P = 0.035). Finally, fetuses requiring postnatal pulmonary valvuloplasty showed a different pattern of echocardiographic findings from those not requiring valvuloplasty, with a significantly smaller RV and pulmonary valve diameter, reduced tricuspid annular-plane systolic excursion (5.08 ± 1.59 vs 8.07 ± 1.93 mm, P = 0.028), increased LV cardiac output (340 ± 16 vs 176 ± 44 mL/min/kg, P = 0.003) and more pronounced signs of LV diastolic dysfunction (mitral E' velocity, 5.78 ± 0.90 vs 8.16 ± 1.58 cm/s, P = 0.008).

CONCLUSIONS

Fetuses with PS present with more hypertrophic, larger and more globular hearts in the third trimester of pregnancy, associated with a higher right cardiac output and impaired biventricular relaxation. In addition, signs of increased LV contraction were observed. Our data suggest that RV and LV functional parameters could be useful for predicting the need for postnatal pulmonary valvuloplasty. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

The boundaries of fetal cardiac intervention: Expand or tighten?

Fetal cardiac intervention (FCI) is a relatively new and continually evolving field, and, for select cardiac defects, offers the potential to alter the progression of the disease and improve outcomes. It is a procedure that requires a collaborative effort between maternal-fetal medicine, interventional cardiology and fetal echo/ultrasound specialists, as well as fetal and maternal anesthesiologists, nursing specialists, and social workers. This article reviews the most recently reported data and advances in FCI. Currently, FCI is most frequently performed in fetuses with severe aortic stenosis (AS) with evolving hypoplastic left heart syndrome (eHLHS), established HLHS with intact or highly restrictive atrial septum (IAS), and pulmonary atresia with intact ventricular septum (PA-IVS) with evolving hypoplastic right heart syndrome (eHRHS). The goal of FCI for eHLHS and eHRHS is to promote a postnatal biventricular circulation with, theoretically, the potential for better long-term outcomes. In HLHS with IAS the aim is to improve survival. Contemporary data for FCI demonstrate limited maternal risks and improving technical success. With experience, FCI in severe AS with eHLHS has shown improved rates of biventricular outcome and early survival. Limited data for PA-IVS show promise for improving postnatal biventricular outcomes; however, for HLHS with IAS, FCI has yet to clearly demonstrate improved survival. FCI has an evolving role in the management of congenital heart defects. Ongoing analysis of disease progression, patient selection and postnatal outcomes, in conjuncture with technologic innovations and a multicenter collaborative approach, is essential as the field expands.

Outcomes After Decompression of the Right Ventricle in Infants With Pulmonary Atresia With Intact Ventricular Septum Are Associated With Degree of Tricuspid Regurgitation

Background—

Outcomes after right ventricle (RV) decompression in infants with pulmonary atresia with intact ventricular septum vary widely. Descriptions of outcomes are limited to small single-center studies.

Methods and Results—

Neonates undergoing RV decompression for pulmonary atresia with intact ventricular septum were included from 4 pediatric centers. Primary end point was reintervention post-RV decompression; secondary end points included circulation type at latest follow-up. Ninety-nine patients (71 with pulmonary atresia with intact ventricular septum and 28 with virtual atresia) underwent RV decompression at median 3 (25th–75th, 2–5) days of age. Seventy-one patients (72%) underwent at least 1 reintervention after decompression. Median duration of follow-up was 3 years (range, 1–10). Freedom from reintervention was 51% at 1 month and 23% at 3 years. In multivariable analysis, reintervention was associated with virtual atresia (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.28–091; P =0.027), smaller RV length (HR, 0.94; 95% CI, 0.89–0.99; P =0.027), and ≤mild tricuspid regurgitation (TR; HR, 3.58; 95% CI, 2.04–6.30; P <0.001). Patients undergoing surgical shunt or ductal stent were less likely to have virtual atresia (HR, 0.36; 95% CI, 0.15–0.85; P =0.02) and more likely to have higher RV end-diastolic pressure (HR, 1.07; 95% CI, 1.00–1.15; P =0.057) and ≤mild TR (HR, 3.50; 95% CI, 1.75–7.0; P <0.001). Number of reinterventions was associated with ≤mild TR (rate ratio, 1.87; 95% CI, 1.23–2.87; P =0.0037). Multivariable analysis indicated that <2-ventricle circulation status was associated with ≤mild TR (odds ratio, 18.6; 95% CI, 5.3–65.2; P <0.001) and lower RV area (odds ratio, 0.81; 95% CI, 0.72–0.91; P <0.001).

Conclusions—

Patients with pulmonary atresia with intact ventricular septum deemed suitable for RV decompression have a high reintervention burden although most achieve 2-ventricle circulation. TR ≤mild at baseline is strongly associated with reintervention and <2-ventricle circulation at medium-term follow-up. Degree of baseline TR may be an important marker of long-term outcomes in this population.

Diverse outcome following early prenatal diagnosis of pulmonary stenosis

OBJECTIVE

To assess the natural history and outcome of fetal pulmonary stenosis (PS), particularly that detected at 14-17 weeks' gestation.

METHODS

In this retrospective study we searched an electronic database of women from the general Israeli population attending a private ultrasound institute (Al-Kol ultrasound institute in Haifa) for routine complete early fetal ultrasound, including all fetal systems and a fetal echocardiogram, between 2004 and 2015. Ninety-seven percent of the women were at low risk of fetal malformations, and 3% had risk factors such as maternal Type-1 diabetes mellitus, exposure during pregnancy to teratogenic drugs, or anomalies in previous pregnancies or in other family members. At presentation at 14-17 weeks of gestation, color and pulsed Doppler imaging were performed across the four cardiac valves. We identified cases in which abnormal flow was detected, leading to suspicion of PS; in these cases, a follow-up examination was carried out at 17-19 weeks and then monthly until delivery or resolution of the finding, and postnatal echocardiography was performed at birth, 4-6 weeks thereafter, and yearly afterwards. Outcome data for suspicious cases, including postnatal diagnosis and general or specific symptoms, were collected by contacting the parents via email or telephone.

RESULTS

Among 24 185 early prenatal transvaginal ultrasound screening examinations, 23 cases of suspected PS were identified. They were classified into three groups, according to their ultrasound findings. In Group A (n = 8), the ultrasound screen was normal except for high flow velocity across the pulmonary valve. In six cases, this finding had resolved by 20-21 weeks of gestation and all were found to be normal at postnatal follow-up, one case underwent termination of pregnancy at 19 weeks and PS was confirmed at autopsy and one case was lost to follow-up. In Group B (n = 12), there was aliasing across the pulmonary valve. Two of these cases were normal postnatally and eight had mild-to-moderate PS; the remaining two cases developed hypoplastic right ventricle and pulmonary atresia at 19-20 weeks and the pregnancies were terminated. In Group C (n = 3) PS was associated with other anomalies; all three pregnancies were terminated. There were an additional six cases (Group D) not identified in early gestation, in which PS was late-onset. One had tricuspid regurgitation at the early screen, but was subsequently diagnosed with Ebstein's anomaly and pulmonary atresia, at 22 weeks, and was terminated. The other cases had completely normal early ultrasound screening examinations: one case had Ebstein's anomaly and PS was diagnosed at birth; four had isolated mild PS, of which one was diagnosed at 22 weeks' gestation and the other three were diagnosed postnatally, before 3 months of age. The sensitivity for detection of the ascertained cases of PS was 64% (11/17) and the specificity was > 99%.

CONCLUSION

There is a diverse spectrum of presentation of fetal PS in the early mid-trimester. A possible explanation for this could be different pathophysiological pathways. Further study is needed to explain the different prenatal sonographic presentations in an unselected population. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Fetal cardiac interventions: clinical and experimental research

Fetal cardiac interventions for congenital heart diseases may alleviate heart dysfunction, prevent them evolving into hypoplastic left heart syndrome, achieve biventricular outcome and improve fetal survival. Candidates for clinical fetal cardiac interventions are now restricted to cases of critical aortic valve stenosis with evolving hypoplastic left heart syndrome, pulmonary atresia with an intact ventricular septum and evolving hypoplastic right heart syndrome, and hypoplastic left heart syndrome with an intact or highly restrictive atrial septum as well as fetal heart block. The therapeutic options are advocated as prenatal aortic valvuloplasty, pulmonary valvuloplasty, creation of interatrial communication and fetal cardiac pacing. Experimental research on fetal cardiac intervention involves technical modifications of catheter-based cardiac clinical interventions and open fetal cardiac bypass that cannot be applied in human fetuses for the time being. Clinical fetal cardiac interventions are plausible for midgestation fetuses with the above-mentioned congenital heart defects. The technical success, biventricular outcome and fetal survival are continuously being improved in the conditions of the sophisticated multidisciplinary team, equipment, techniques and postnatal care. Experimental research is laying the foundations and may open new fields for catheter-based clinical techniques. In the present article, the clinical therapeutic options and experimental fetal cardiac interventions are described.

Fetal interventions for congenital heart disease

PURPOSE OF REVIEW

This article discusses the rationale, patient selection, technical aspects, and outcomes of percutaneous, ultrasound-guided fetal cardiac intervention (FCI) for structural congenital heart disease.

RECENT FINDINGS

FCI is most commonly performed for three forms of congenital heart disease: severe aortic stenosis with evolving hypoplastic left heart syndrome (HLHS), pulmonary atresia with intact ventricular septum and evolving hypoplastic right heart syndrome, and HLHS with intact or highly restrictive atrial septum. For severe aortic stenosis and pulmonary atresia with intact ventricular septum, the goal of intervention is to alter the natural history such that a biventricular circulation may be achieved postnatally. A growing number of patients have achieved a biventricular circulation; however, patient selection and postnatal management strategy are essential for success. HLHS with intact or highly restrictive atrial septum is one of the most lethal forms of congenital heart disease, and the goal of FCI is to improve survival. Although the creation of an atrial communication in utero is technically feasible and may permit greater stability in the immediate postnatal period, significant improvements in survival have not yet been reported.

SUMMARY

FCI is an evolving form of treatment for congenital heart disease that holds promise for select patients. Critical evaluation of both short and long-term outcomes is warranted.

Echocardiographic factors discriminating biventricular versus univentricular approach in the foetus with borderline left ventricle

BACKGROUND

The term "borderline left ventricle" describes a small left heart that may be inadequate to provide systemic cardiac output and implies the potential need for a single-ventricle palliation. The aim of this study was to identify foetal echocardiographic features that help discriminate which infants will undergo single-ventricle palliation versus biventricular repair to aid in prenatal counselling.

METHODS

The foetal database at our institution was searched to identify all foetuses with borderline left ventricle, as determined subjectively by a foetal cardiologist, from 2000 to 2011. The foetal images were retrospectively analysed for morphologic and physiologic features to determine which best predicted the postnatal surgical choice.

RESULTS

Of 39 foetuses identified with borderline left ventricle, 15 were planned for a univentricular approach, and 24 were planned for a biventricular approach. There were significant differences between the two outcome groups in the Z-scores of the mitral valve annulus, left ventricular end-diastolic dimension, aortic valve annulus, and ascending aorta diameter (p<0.05). With respect to discriminating univentricular outcomes, cut-offs of mitral valve Z-score ⩽-1.9 and tricuspid:mitral valve ratio ⩾1.5 were extremely sensitive (100%), whereas a right:left ventricular end-diastolic dimension ratio ⩾2.1 provided the highest specificity (95.8%).

CONCLUSION

In foetuses with borderline left ventricle, a mitral valve Z-score ⩾-1.9 or a tricuspid:mitral valve ratio ⩽1.5 suggests a high probability of biventricular repair, whereas a right:left ventricular end-diastolic dimension ratio ⩾2.1 confers a likelihood of single-ventricle palliation.

Prenatal diagnosis of multiple ventriculocoronary connections in pulmonary atresia with an intact ventricular septum: a case report

We report a case of prenatally detected pulmonary atresia with an intact ventricular septum accompanied by multiple ventriculocoronary connections. This lesion was diagnosed by using ultrasonography at 20 weeks' gestation, and this antepartum diagnosis was confirmed with both postnatal echocardiography and chest computed tomography. The neonate underwent a modified Blalock-Taussig shunt on the 15th day of life, and was discharged 8 days after the surgery.

Factors associated with in utero demise of fetuses that have underlying cardiac pathologies

Factors associated with in utero fetal demise (IUFD) of fetuses that have underlying cardiac pathologies are largely unknown. This case-control study aimed to define the prevalence of IUFD in fetuses with a diagnosis of cardiac pathologies and to identify prenatal predictors of IUFD. Between January 2004 and December 2010, 74 IUFD cases [4.6 %; 95 % confidence interval (CI) 3.7-5.8 %] were identified from 1,584 cases with a diagnosis of structural or functional cardiac lesions in the Hospital for Sick Children database. The cases were divided into right-sided (N = 28), left-sided (N = 23), great artery (N = 8), and miscellaneous (N = 15) groups. The control subjects (1:1 ratio) were fetuses that had cardiac pathology diagnosed within 48 h of the IUFD case. Multivariable regression models were used to determine echocardiographic predictors of IUFD. The prevalence of IUFD was greatest in hypertrophic cardiomyopathy (8/16, 50 %) and Ebstein's anomaly/tricuspid dysplasia (4/15, 27 %) and lowest in transposition of the great arteries (2/85, 1 %). The findings showed IUFD to be associated with hydrops in 17 (23 %) of the 74 cases and arrhythmia in 11 (15 %) of the 74 cases. The factors identified by univariable logistic regression analyses were right ventricular dysfunction [odds ratio (OR) 2.7; p = 0.001], left ventricular dysfunction (OR 1.8; p = 0.007), umbilical vein pulsations (OR 10.9; p = 0.002), and abnormal ductus venosus flow (OR 3.3; p = 0.01). The factors associated with IUFD in multivariable logistic regression models were cardiomegaly (OR 5.6; p = 0.01), hydrops (OR 29.5; p = 0.001), pericardial effusion (OR 4.1; p = 0.06), and extracardiac abnormalities (OR 7.2; p < 0.001). The prevalence of IUFD is greatest in conditions affecting the ventricular myocardium. The onset of IUFD appears to be related initially to right ventricular dysfunction. Closer surveillance is recommended for lesions at risk of IUFD.

Diagnosis and treatment of fetal cardiac disease: a scientific statement from the American Heart Association

BACKGROUND

The goal of this statement is to review available literature and to put forth a scientific statement on the current practice of fetal cardiac medicine, including the diagnosis and management of fetal cardiovascular disease.

METHODS AND RESULTS

A writing group appointed by the American Heart Association reviewed the available literature pertaining to topics relevant to fetal cardiac medicine, including the diagnosis of congenital heart disease and arrhythmias, assessment of cardiac function and the cardiovascular system, and available treatment options. The American College of Cardiology/American Heart Association classification of recommendations and level of evidence for practice guidelines were applied to the current practice of fetal cardiac medicine. Recommendations relating to the specifics of fetal diagnosis, including the timing of referral for study, indications for referral, and experience suggested for performance and interpretation of studies, are presented. The components of a fetal echocardiogram are described in detail, including descriptions of the assessment of cardiac anatomy, cardiac function, and rhythm. Complementary modalities for fetal cardiac assessment are reviewed, including the use of advanced ultrasound techniques, fetal magnetic resonance imaging, and fetal magnetocardiography and electrocardiography for rhythm assessment. Models for parental counseling and a discussion of parental stress and depression assessments are reviewed. Available fetal therapies, including medical management for arrhythmias or heart failure and closed or open intervention for diseases affecting the cardiovascular system such as twin-twin transfusion syndrome, lung masses, and vascular tumors, are highlighted. Catheter-based intervention strategies to prevent the progression of disease in utero are also discussed. Recommendations for delivery planning strategies for fetuses with congenital heart disease including models based on classification of disease severity and delivery room treatment will be highlighted. Outcome assessment is reviewed to show the benefit of prenatal diagnosis and management as they affect outcome for babies with congenital heart disease.

CONCLUSIONS

Fetal cardiac medicine has evolved considerably over the past 2 decades, predominantly in response to advances in imaging technology and innovations in therapies. The diagnosis of cardiac disease in the fetus is mostly made with ultrasound; however, new technologies, including 3- and 4-dimensional echocardiography, magnetic resonance imaging, and fetal electrocardiography and magnetocardiography, are available. Medical and interventional treatments for select diseases and strategies for delivery room care enable stabilization of high-risk fetuses and contribute to improved outcomes. This statement highlights what is currently known and recommended on the basis of evidence and experience in the rapidly advancing and highly specialized field of fetal cardiac care.

Fetal cardiac function in recipient twins undergoing fetoscopic laser ablation of placental anastomoses for Stage IV twin-twin transfusion syndrome

OBJECTIVE

Cardiac dysfunction is common in the recipient fetus of twin-twin transfusion syndrome (TTTS). In this study, we aimed to document the severity of fetal cardiac dysfunction in Stage IV TTTS (fetal hydrops) and assess evolution of cardiac function longitudinally after fetoscopic laser surgery.

METHODS

We reviewed obstetric ultrasound examination data, pre- and postoperative echocardiograms and neonatal outcomes for 22 cases of Stage IV TTTS undergoing fetoscopic laser ablation of placental anastomoses between 1998 and 2011. Myocardial performance index, atrioventricular valve flow patterns, ventricular shortening fraction, ventricular hypertrophy, outflow tract obstruction and venous Doppler waveforms were assessed.

RESULTS

Nineteen fetuses (86.4%) had ascites, eight (36.4%) had pleural effusions, nine (40.9%) had a pericardial effusion and 12 (54.5%) had subcutaneous edema at presentation. Preoperatively, cardiac function was grossly abnormal in all. Eight fetuses (36.4%) had functional pulmonary atresia and one (4.5%) had functional aortic atresia. Seventy-seven percent of recipient fetuses survived until birth. Postoperative echocardiographic follow-up (mean, 26 days) showed that indices of fetal cardiac function improved considerably, but never completely normalized. Six of the eight fetuses with functional pulmonary atresia (75.0%), as well as the fetus with functional aortic atresia, survived to birth. In all cases, the functional atresia resolved within 48 h of laser ablation therapy and none had structural valve anomalies at birth. All fetal effusions resolved after the laser.

CONCLUSIONS

Fetoscopic laser ablation of placental anastomoses reverses cardiac dysfunction and valvulopathy, even in the most severe cases of TTTS. However, recovery takes longer than in early stage disease.

Diagnosis and management of fetal heart failure

Congestive fetal heart failure, defined as inability of the heart to deliver adequate blood flow to organs such as the brain, liver, and kidneys, is a common final outcome of many intrauterine disease states that may lead to fetal demise. Advances in fetal medicine during the past 3 decades now provide the diagnostic tools to detect and also treat conditions that may lead to fetal heart failure. Fetal echocardiographic findings depend on severity of diastolic and systolic dysfunction of both ventricles. At an advanced stage, findings include cardiomegaly; valvar regurgitation; venous congestion; fetal edema and effusions; oligohydramnios; and preferential shunting of blood flow to the brain, heart, and adrenals in the distressed fetus. A useful diagnostic tool to quantify severity of heart failure is the cardiovascular profile score, which is a composite score based on 5 different echocardiographic parameters. To predict outcomes, the score should be interpreted in the context of the underlying disease, as different causes of intrauterine heart failure may have highly variable outcomes. Low fetal cardiac output may result from a myocardial disease (cardiomyopathy, myocarditis, ischemia), abnormal loading conditions (arterial hypertension, obstructive structural heart disease, atrioventricular malformations, twin-to-twin transfusion), arrhythmia, or external cardiac compression (pleural and/or pericardial effusions, cardiac tumours). Treatment options are available for several of these conditions.

Fetal intervention in right outflow tract obstructive disease: selection of candidates and results

Objectives. To describe the process of selection of candidates for fetal cardiac intervention (FCI) in fetuses diagnosed with pulmonary atresia-critical stenosis with intact ventricular septum (PA/CS-IVS) and report our own experience with FCI for such disease. Methods. We searched our database for cases of PA/CS-IVS prenatally diagnosed in 2003–2012. Data of 38 fetuses were retrieved and analyzed. FCI were offered to 6 patients (2 refused). In the remaining it was not offered due to the presence of either favourable prognostic echocardiographic markers (n = 20) or poor prognostic indicators (n = 12). Results. The outcome of fetuses with PA/CS-IVS was accurately predicted with multiparametric scoring systems. Pulmonary valvuloplasty was technically successful in all 4 fetuses. The growth of the fetal right heart and hemodynamic parameters showed a Gaussian-like behaviour with an improvement in the first weeks and slow worsening as pregnancy advanced, probably indicating a restenosis. Conclusions. The most likely type of circulation after birth may be predicted in the second trimester of pregnancy by means of combining cardiac dimensions and functional parameters. Fetal pulmonary valvuloplasty in midgestation is technically feasible and in well-selected cases may improve right heart growth, fetal hemodynamics, and postnatal outcome.

Progression of outflow tract obstruction in the fetus

Fetal ventricular outflow tract obstruction (OTO) is congenital heart disease with significant potential for progression before birth as a consequence of the unique nature of the fetal circulation. The pattern of evolution depends upon the timing of development, severity of obstruction and the influence of the OTO on the fetal atrioventricular valve and myocardial function. Critical aortic (AS) or pulmonary (PS) valve stenosis, the two most common forms of fetal OTO, may be associated with progressive ventricular and great artery hypoplasia if presenting early in gestation or with normal ventricular and great artery growth if evolving later in gestation. In some affected fetuses, AS or PS may lead to the evolution of fetal heart failure. This article will review our current understanding of the natural history of fetal AS and PS, experience with fetal intervention and future directions of research.

Impact of prenatal diagnosis on outcome of pulmonary atresia and intact ventricular septum

OBJECTIVES

To determine the impact of fetal echocardiography on the management of pregnancy and of newborns affected by pulmonary atresia and intact ventricular septum (PAIVS) and to evaluate the outcome of infants with and without prenatal diagnosis of PAIVS.

METHODS

We searched our database for cases of PAIVS prenatally and postnatally diagnosed during the period January 1993-December 2009. Postnatal follow-up was available in all cases included in the study. Karyotyping and fluorescent in situ hybridization analysis for the DiGeorge critical region (22q11.2) were performed in all but one case.

RESULTS

The study comprised 60 cases of PAIVS: 36 with (Group A) and 24 without (Group B) prenatal diagnosis. In Group A, there were two intrauterine deaths, six postnatal deaths (five early after birth) and one termination of pregnancy. In this group, radiofrequency (RF) perforation was successfully performed in 25 cases; 20/25 infants had a biventricular (BV) repair, without further operation in 13 of them. No patient of Group B died. In this group, RF perforation was successfully performed in 22 cases; 20/22 had a BV repair without further procedure in 15 of them.

CONCLUSIONS

Prenatal diagnosis of PAIVS allows a reliable prognosis of severity and planning of proper surgical repair strategies. Fetuses that are prenatally diagnosed present a more severe spectrum of the disease; for the cases capable of getting through the neonatal period, the mortality rate and the need for further intervention were not significantly different when compared with babies with only postnatal diagnosis.

[Pulmonary stenosis and atresia with intact ventricular septum]

Pulmonary atresia and critical pulmonary stenosis with intact ventricular septum includes a wide spectrum of cardiopathies with great morphological heterogeneity. The pulmonary valve may be completely atretic or may contain a puncture hole if stenosis is present. The obstruction may be membranous and/or muscular. All components of the right ventricle can be affected, even the coronary circulation with ventriculocoronary connections and stenosis or atresia of the pulmonary arteries. Prenatal diagnosis is made when the right ventricle is hypoplastic and hypertrophic. The pulmonary valve is thickened and the pulmonary artery is perfused retrogradely through the ductus arteriosus. Right ventriculocoronary connections may sometimes be seen with fetal echocardiography. Postnatal survival depends on the patency of the ductus arteriosus, requiring prostaglandin E1 infusion. When hypoplastic right ventricle and/or ventricle-dependent coronary circulation exists, biventricular circulation is not possible. In these cases, surgical treatment is palliative. In cases with well-developed right ventricle, transcatheter therapy is usually provided with perforation and balloon dilation of the pulmonary valve. In cases of muscular obstruction of the right ventricle outflow tract, surgery may be considered as first-line therapy. In case of prenatal diagnosis, the medical termination of pregnancy is possible when severe right ventricular hypoplasia exists, precluding biventricular circulation. Postnatally, the prognosis of the patients is highly variable, mainly related to the size of the right cavities and the presence of coronary anomalies.