- [Show abstract] [Hide abstract] ABSTRACT: Objectives: Although the postnatal physiology of D-loop transposition of the great arteries with intact ventricular septum (DTGA-IVS) is well established, little is known about fetal DTGA-IVS. In the normal fetus, the pulmonary valve (PV) is larger than the aortic valve (AoV), there is exclusive right to left flow at the foramen ovale (FO) and ductus arteriosus (DA), and the left ventricle (LV) ejects 40% of combined ventricular output (CVO) through the aorta, primarily to the brain. In DTGA-IVS, the LV ejects O2 -rich blood to the pulmonary artery, theoretically leading to pulmonary vasodilation, increased branch pulmonary arterial flow and reduced DA flow. We tested the hypothesis that TGA anatomy results in altered distribution of CVO, FO and DA flow, and valve size. Methods: We analyzed valve size, color flow and pulse Doppler on echocardiograms of 74 fetuses with DTGA-IVS (2004-2015). Findings were compared with our institutional normal fetal data, n = 222. Results: The LV component of CVO was higher in TGA than in controls (50.7% vs 40.2%, p < 0.001) with no difference in total CVO. Flow was bidirectional at the FO in 56 (75.7%) fetuses and at the DA in 24 (32.4%). Only 21.6% had normal exclusive right to left flow at both shunts. Bidirectional shunting was more common in the 3(rd) trimester than the 2(nd) (p < 0.03). In contrast to normal, D-TGA AoV and PV sizes were nearly identical, hence the AoV z-score was higher than the PV z-score (1.13 vs -0.65, p < 0.001). Conclusions: In DTGA-IVS there is loss of normal right sided dominance, as each ventricle provides half of the CVO, with a relatively large AoV and small PV, and frequently bidirectional FO and DA flow. This may support the theory that high pulmonary arterial O2 content lowers pulmonary vascular resistance, thereby increasing branch pulmonary arterial flow and venous return, increasing LV preload and output. Pulmonary sensitivity to O2 is thought to increase later in gestation, which may explain the increased bidirectional shunting. Consequences of these flow alterations include increased aortic and likely brain flow, perhaps compensating for substrate deficiency in DTGA-IVS.
- [Show abstract] [Hide abstract] ABSTRACT: In fetuses with Ebstein anomaly or tricuspid valve dysplasia (EA/TVD), poor hemodynamic status is associated with worse neonatal outcome. It is not known whether EA/TVD fetuses with more favorable physiology earlier in gestation progress to more severe disease in the 3rd trimester. We evaluated if echocardiographic indices in EA/TVD fetuses presenting <24 weeks gestation are reliable indicators of physiologic status later in pregnancy. This multi-center, retrospective study included 51 fetuses presenting at <24 weeks gestation with EA/TVD and serial fetal echocardiograms ≥4 weeks apart. We designated the following as markers of poor outcome: absence of antegrade flow across the pulmonary valve, pulmonary valve regurgitation (PR), cardiothoracic area ratio (CTA) >0.48, left ventricular (LV) dysfunction or tricuspid valve (TV) annulus Z-score >5.6. Median gestational age at diagnosis was 21 weeks [range, 18-24]. Eighteen (35%) fetuses had no markers for poor hemodynamic status initially, while only 7 of these continued to have no markers of poor outcome in the 3rd trimester. Nine of 27 fetuses (33%) with antegrade pulmonary blood flow on the first echocardiogram developed pulmonary atresia; 7/39 (18%) developed new PR. LV dysfunction was present in 2 (4%) patients at <24 weeks but in 14 (37%) later (p<0.01). The TV annulus Z-score and CTA both increased from diagnosis to follow-up. In conclusion, progressive hemodynamic compromise was common in this cohort. Our study highlights that care must be taken in counseling prior to 24 weeks, as the absence of factors associated with poor outcome early in pregnancy may be falsely reassuring.
- [Show abstract] [Hide abstract] ABSTRACT: Fetuses with hypoplastic left heart syndrome (HLHS) and intact atrial septum are a particular subset of HLHS neonates with high perinatal mortality. The reported mortality in these patients is 50% to 70%, even with prenatal diagnosis. Prenatal left atrial and pulmonary venous hypertension results in abnormal pulmonary vascular and parenchymal development. The goal of this study was to compare the sonographic appearance of the lungs in fetuses with HLHS/intact atrial septum to neonatal outcome and/or pathology in cases where in utero intervention was performed to open the atrial septum. We found that lung inhomogeneity on ultrasound corresponded to peripheral lymphatic dilatation at autopsy and was associated with a dismal prognosis even when in utero intervention was successful.
- [Show abstract] [Hide abstract] ABSTRACT: Objectives: Mitral valve replacement (MVR) in young children is limited by the lack of small prostheses. Our institution began performing MVR with modified, surgically placed, stented jugular vein grafts (Melody valve) in 2010. We sought to describe key echocardiographic features for pre- and postoperative assessment of this novel form of MVR. Methods: The pre- and postoperative echocardiograms of 24 patients who underwent Melody MVR were reviewed. In addition to standard measurements, preoperative potential measurements of the mitral annulus were performed whereby dimensions were estimated for Melody sizing. A ratio of the narrowest subaortic region in systole to the actual mitral valve dimension (SubA:MV) was assessed for risk of postoperative left ventricular outflow tract obstruction (LVOTO). Results: Melody MVR was performed at a median of 8.5 months (5.6 kg) for stenosis (5), regurgitation (3), and mixed disease (16). Preoperatively, actual mitral z scores measured hypoplastic (median -3.1 for the lateral [lat] dimension; -2.1 for the anteroposterior [AP] dimension). The potential measurements often had normal z scores with fair correlation with intraoperative Melody dilation (ρ = 0.51 and 0.50 for lat and AP dimensions, respectively, both P = .01). A preoperative SubA:MV <0.5 was associated with postoperative LVOTO, which occurred in 4 patients. Postoperatively, mitral gradients substantially improved, with low values relative to the effective orifice area of the Melody valve. No patients had significant regurgitation or perivalvar leak. Conclusions: Preoperative echocardiographic measurements may help guide intraoperative sizing for Melody MVR and identify patients at risk for postoperative LVOTO. Acute postoperative hemodynamic results were favorable; however, ongoing assessment is warranted.
- [Show abstract] [Hide abstract] ABSTRACT: Objectives: To assess cardiac sequelae of fetal cerebral arteriovenous malformations (CAVMs) and evaluate any association with outcomes. Methods: We retrospectively analyzed cardiac structure and function in fetuses with CAVMs who underwent fetal echocardiography (October 1999 to August 2015, n = 11), and compared them with normal controls. Results: The median gestational age was 36 weeks (range 18-38). Common abnormal findings included dilated superior vena cava (100%) and right atrium (82%), reduced middle cerebral artery pulsatility index (86%), tricuspid regurgitation (82%), and right ventricular (RV) dysfunction (64%). Hydrops was present in 1 fetus, who did not survive. The median cardiothoracic ratio (CTR) was 0.36 (0.29-0.45, n = 10); the median combined cardiac output indexed to estimated fetal weight (iCCO) was 565 ml/kg/min (379-1,565, n = 7). Of the 11 fetuses, 1 patient elected for termination, and 5 suffered neonatal demise. Comparing survivors (n = 5) and nonsurvivors (n = 6), a larger tricuspid valve (TV) z-score (p = 0.009) and RV dysfunction (p = 0.015) were associated with nonsurvival, and nonsurvivors had a higher iCCO than controls (990 vs. 550 ml/kg/min, p = 0.035). A larger difference between the TV and mitral valve z-scores (surrogate for RV dilation, p = 0.052), and CTR >0.38 (p = 0.0762) tended towards nonsurvival. Conclusion: CAVMs impose volume load on the fetal circulation, mainly affecting right heart structures. Increased right heart dilation and dysfunction are associated with nonsurvival.
- [Show abstract] [Hide abstract] ABSTRACT: Background and purpose: Brain injury in neonates with congenital heart disease is an important predictor of adverse neurodevelopmental outcome. Impaired brain development in congenital heart disease may have a prenatal origin, but the sensitivity and specificity of fetal brain MR imaging for predicting neonatal brain lesions are currently unknown. We sought to determine the value of conventional fetal MR imaging for predicting abnormal findings on neonatal preoperative MR imaging in neonates with complex congenital heart disease. Materials and methods: MR imaging studies were performed in 103 fetuses with confirmed congenital heart disease (mean gestational age, 31.57 ± 3.86 weeks) and were repeated postnatally before cardiac surgery (mean age, 6.8 ± 12.2 days). Each MR imaging study was read by a pediatric neuroradiologist. Results: Brain abnormalities were detected in 17/103 (16%) fetuses by fetal MR imaging and in 33/103 (32%) neonates by neonatal MR imaging. Only 9/33 studies with abnormal neonatal findings were preceded by abnormal findings on fetal MR imaging. The sensitivity and specificity of conventional fetal brain MR imaging for predicting neonatal brain abnormalities were 27% and 89%, respectively. Conclusions: Brain abnormalities detected by in utero MR imaging in fetuses with congenital heart disease are associated with higher risk of postnatal preoperative brain injury. However, a substantial proportion of anomalies on postnatal MR imaging were not present on fetal MR imaging; this result is likely due to the limitations of conventional fetal MR imaging and the emergence of new lesions that occurred after the fetal studies. Postnatal brain MR imaging studies are needed to confirm the presence of injury before open heart surgery.
- [Show abstract] [Hide abstract] ABSTRACT: 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.
- [Show abstract] [Hide abstract] ABSTRACT: The most commonly performed fetal cardiac intervention (FCI) is aortic balloon valvuloplasty. The primary aim of fetal aortic valvuloplasty is to modify the in utero natural history of severe aortic stenosis, characterized by left heart growth arrest, and prevent progression to hypoplastic left heart syndrome (HLHS).
- [Show abstract] [Hide abstract] ABSTRACT: Invasive fetal cardiac intervention (FCI) has been reported in single-institution series, promoting technical and physiologic success. This study describes the creation of an international registry of cases presenting for FCI, intended to compile technical and outcome data from a multicenter cohort. For this initial analysis, the entire database of the International Fetal Cardiac Intervention Registry (IFCIR) was queried for details of diagnoses, procedures, and outcomes. Maternal-fetal dyads from January 2001 through June 2014 were included. Eighteen institutions submitted data by data harvest. Of 370 cases entered, 245 underwent FCI: 100 aortic valvuloplasties from a previous single-center report (excluded from additional reporting here), an additional 86 aortic and 16 pulmonary valvuloplasties, 37 atrial septal cases, and 6 unclassified cases. FCI did not appear to affect overall survival to hospital discharge. Among live-born infants with a fetal diagnosis of aortic stenosis/evolving hypoplastic left heart syndrome, more than twice as many were discharged with biventricular circulation after successful FCI versus those meeting institutional criteria but without any or successful FCI (42.8% vs. 19.4%, respectively). When fetal deaths were counted as treatment failures, the percentages were similar: biventricular circulation at discharge was 31.3% versus 18.5% for those discharged with univentricular palliation. Survival to discharge for live-born fetuses with atrial restriction was similar to that of those undergoing technically successful versus unsuccessful FCI (63.6% vs. 46.7%, respectively), although criteria for diagnosis were nonuniform. We describe the contents of the IFCIR and present post-natal data to suggest potential benefit to fetal therapy among pregnancies considered for possible intervention and support proposals for additional work. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: -Ebstein anomaly and tricuspid valve dysplasia (EA/TVD) are rare congenital tricuspid valve malformations associated with high perinatal mortality. The literature consists of small, single-center case series spanning several decades. We performed a multi-center study to assess outcomes and factors associated with mortality after fetal diagnosis in the current era. -Fetuses diagnosed with EA/TVD from 2005-2011 were included from 23 centers. The primary outcome was perinatal mortality, defined as fetal demise or death prior to neonatal discharge. Of 243 fetuses diagnosed at a mean gestational age (GA) of 27 ± 6 weeks, there were 11 lost to follow-up (5%), 15 terminations (6%), and 41 demises (17%). In the live-born cohort of 176 live-born patients, 56 (32%) died prior to discharge, yielding an overall perinatal mortality of 45%. Independent predictors of mortality at the time of diagnosis were GA <32 weeks (odds ratio (OR) 8.6 [95% confidence interval: 3.5 - 21.0]; p<0.001), tricuspid valve annulus diameter z-score (OR 1.3 [1.1 - 1.5]; p<0.001), pulmonary regurgitation (PR) (OR 2.9 [1.4 - 6.2]; p<0.001), and a pericardial effusion (OR 2.5 [1.1 - 6.0]; p=0.04). Non-survivors were more likely to have PR at any GA (61% vs. 34%; p<0.001), as well as lower GA and weight at birth (35 vs. 37 weeks; 2.5 vs. 3.0 kg; both p<0.001). -In this large, contemporary series of fetuses with EA/TVD, perinatal mortality remained high. Fetuses with PR, indicating circular shunt physiology, are a high-risk cohort and may benefit from more innovative therapeutic approaches to improve survival.
- [Show abstract] [Hide abstract] ABSTRACT: Fetal aortic valvuloplasty (FAV) has shown promise in averting the progression of fetal aortic stenosis to hypoplastic left-heart syndrome. Altered loading conditions due to valvar disease, intrinsic endomyocardial abnormalities, and procedures that alter endomyocardial mechanics may place patients with biventricular circulation (BiV) after FAV at risk of abnormal LV remodeling and function. Using the most recent echo data on BiV patients after technically successful FAV (n = 34), we evaluated LV remodeling pattern, risk factors for pathologic LV remodeling, and the association between LV remodeling pattern and LV function. Median age at follow-up was 4.7 years (range 1.0-12.5). Cardiac interventions were common. At latest follow-up, no patient had hypoplastic LV. Nineteen patients (55 %) had dilated LV, and five (16 %) patients had severely dilated LV. LV remodeling patterns were as follows: 12 (35 %) normal ventricle, 11 (32 %) mixed hypertrophy, 8 (24 %) eccentric hypertrophy or remodeling, and 3 (9 %) concentric hypertrophy. Univariate factors associated with pathologic LV remodeling were long-standing AR, ≥2 cardiac interventions, EFE resection, and aortic or mitral regurgitation ≥ moderate at most recent follow-up. In multivariate analysis, only long-standing AR fraction remained associated with pathologic remodeling. Pathologic LV remodeling was associated with depressed ejection fraction, lower septal E´, and higher E/E´. Pathologic LV remodeling, primarily eccentric or mixed hypertrophy, is common in BiV patients after FAV and is related to LV loading conditions imposed by valvar disease. Pathologic remodeling is associated with both systolic and diastolic dysfunction in this population.
- [Show abstract] [Hide abstract] ABSTRACT: To evaluate temporal trends in prenatal diagnosis of transposition of the great arteries with intact ventricular septum (TGA/IVS) and its impact on neonatal morbidity and mortality. Newborns with TGA/IVS referred for surgical management to our center over a 20-year period (1992 - 2011) were included. The study time was divided into 5 four-year periods, and the primary outcome was rate of prenatal diagnosis. Secondary outcomes included neonatal pre-operative status and perioperative survival. Of the 340 patients, 81 (24%) had a prenatal diagnosis. Prenatal diagnosis increased over the study period from 6% to 41% (p < 0.001). Prenatally diagnosed patients underwent a balloon atrial septostomy (BAS) earlier than postnatally diagnosed patients (0 vs. 1 day, p < 0.001) and fewer required mechanical ventilation (56% vs. 69%, p = 0.03). There were no statistically significant differences in pre-operative acidosis (16% vs. 26%, p = 0.1) and need for preoperative ECMO (2% vs. 3%, p = 1.0). There was also no significant mortality difference (1 pre-operative and no post-operative deaths among prenatally diagnosed patients, as compared to 4 pre-operative and 6 post-operative deaths among postnatally diagnosed patients). The prenatal detection rate of TGA/IVS has improved but still remains below 50%, suggesting the need for strategies to increase detection rates. The mortality rate was not statistically different between pre- and postnatally diagnosed patients; however, there were significant pre-operative differences with regard to earlier BAS and less mechanical ventilation. Ongoing study is required to elucidate whether prenatal diagnosis confers long-term benefit. This article is protected by copyright. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: Objectives To better understand the natural history and spectrum of fetal aortic stenosis (AS), we aimed to 1) determine the prenatal diagnosis rate of neonates with critical AS and a biventricular (BV) outcome; and 2) describe the findings at fetal echocardiography in prenatally diagnosed patients.MethodsA multi-center, retrospective study was performed from 2000 to 2013. Neonates with critical AS who were discharged with a BV outcome were included. The prenatal diagnosis rate was compared to that reported for hypoplastic left heart syndrome (HLHS). Fetal echocardiographic findings in prenatally diagnosed patients were reviewed.ResultsOnly 10 of 117 neonates (8.5%) with critical AS and a BV outcome were diagnosed prenatally, a rate significantly lower than that for HLHS in the contemporary era (82%; p < 0.0001). Of the 10 patients diagnosed prenatally, all developed LV dysfunction by a median gestational age of 33 weeks (range, 28-35). When present, Doppler abnormalities such as retrograde flow in the aortic arch (n = 2), monophasic mitral inflow (n = 2), and left to right flow across the foramen ovale (n = 8) developed late in gestation (median 33 weeks).Conclusion The prenatal diagnosis rate among neonates with critical AS and a BV outcome is very low, likely due to a relatively normal 4-chamber view in mid-gestation with development of significant obstruction in the 3rd trimester. This natural history contrasts with that of severe mid-gestation AS with evolving HLHS and suggests that the timing in gestation of significant AS has an important impact on subsequent left heart growth in utero.
- [Show abstract] [Hide abstract] ABSTRACT: Background: Fetal aortic valvuloplasty can be performed for severe midgestation aortic stenosis in an attempt to prevent progression to hypoplastic left heart syndrome (HLHS). A subset of patients has achieved a biventricular (BV) circulation after fetal aortic valvuloplasty. The postnatal outcomes and survival of the BV patients, in comparison with those managed as HLHS, have not been reported. Methods and results: We included 100 patients who underwent fetal aortic valvuloplasty for severe midgestation aortic stenosis with evolving HLHS from March 2000 to January 2013. Patients were categorized based on postnatal management as BV or HLHS. Clinical records were reviewed. Eighty-eight fetuses were live-born, and 38 had a BV circulation (31 from birth, 7 converted after initial univentricular palliation). Left-sided structures, namely aortic and mitral valve sizes and left ventricular volume, were significantly larger in the BV group at the time of birth (P<0.01). After a median follow-up of 5.4 years, freedom from cardiac death among all BV patients was 96±4% at 5 years and 84±12% at 10 years, which was better than HLHS patients (log-rank P=0.04). There was no cardiac mortality in patients with a BV circulation from birth. All but 1 of the BV patients required postnatal intervention; 42% underwent aortic or mitral valve replacement. On the most recent echocardiogram, the median left ventricular end-diastolic volume z score was +1.7 (range, -1.3 to +8.2), and 80% had normal ejection fraction. Conclusions: Short- and intermediate-term survival among patients who underwent fetal aortic valvuloplasty and achieved a BV circulation postnatally is encouraging. However, morbidity still exists, and ongoing assessment is warranted.
Boston Children's Hospital
Boston, Massachusetts, United States
- Department of Cardiac Surgery