Mitral valve orifice area predicts outcome after biventricular repair in patients with hypoplastic left ventricles.

BACKGROUND: Identification of risk factors for biventricular (BiV) repair in children with hypoplastic left ventricles (HLV) has been challenging. We sought to identify preoperative cardiovascular magnetic resonance (CMR) predictors of outcome in patients with HLVs who underwent BiV repair, with a focus on the mitral valve (MV). METHODS: Single-center retrospective analysis of preoperative CMRs on patients with HLV (≤50 mL/m2) and no endocardial fibroelastosis who underwent BiV repair from 2005-2022. CMR measurements included MV orifice area in diastole. The primary composite outcome included time to death, transplant, BiV takedown, heart failure admission, left atrial decompression, or unexpected reoperation; and the secondary outcome included more than or equal to moderate mitral stenosis and/or regurgitation. RESULTS: Median follow-up was 0.7 (interquartile range 0.1, 2.2) years. Of 122 patients [59 atrioventricular canal (AVC) and 63 non-AVC] age 3 ± 2.8 years at the time of BiV repair, freedom from the primary outcome at 2 years was 53% for AVC and 69% for non-AVC (log rank p = 0.12), and freedom from the secondary outcome at 2 years was 49% for AVC and 79% for non-AVC (log rank p < 0.01). Independent predictors of primary outcome for AVC patients included MV orifice area z-score <-2 and transitional AVC; for non-AVC patients, predictors included MV orifice area z-score <-2, abnormal MV anatomy, and conal-septal ventricular septal defect. Independent predictors of secondary outcome for AVC patients included older age at surgery, transitional AVC, and transposition of the great arteries. CONCLUSION: In children with HLV, low MV orifice area and pre-existing MV pathology are risk factors for adverse outcome after BiV repair.

Thoracic duct drainage patterns in heterotaxy.

BACKGROUND: Disordered lymphatic drainage is common in congenital heart diseases (CHD), but thoracic duct (TD) drainage patterns in heterotaxy have not been described in detail. This study sought to describe terminal TD sidedness in heterotaxy and its associations with other anatomic variables. METHODS: This was a retrospective, single-center study of patients with heterotaxy who underwent cardiovascular magnetic resonance imaging at a single center between July 1, 2019 and May 15, 2023. Patients with (1) asplenia (right isomerism), (2) polysplenia (left isomerism) and (3) pulmonary/abdominal situs inversus (PASI) plus CHD were included. Terminal TD sidedness was described as left-sided, right-sided, or bilateral. RESULTS: Of 115 eligible patients, the terminal TD was visualized in 56 (49%). The terminal TD was left-sided in 25 patients, right-sided in 29, and bilateral in two. On univariate analysis, terminal TD sidedness was associated with atrial situs (p = 0.006), abdominal situs (p = 0.042), type of heterotaxy (p = 0.036), the presence of pulmonary obstruction (p = 0.041), superior vena cava sidedness (p = 0.005), and arch sidedness (p < 0.001). On multivariable analysis, only superior vena cava and aortic arch sidedness were independently associated with terminal TD sidedness. CONCLUSIONS: Terminal TD sidedness is highly variable in patients with heterotaxy. Superior vena cava and arch sidedness are independently associated with terminal TD sidedness. Type of heterotaxy was not independently associated with terminal TD sidedness. This data improves the understanding of anatomic variation in patients with heterotaxy and may be useful for planning for lymphatic interventions.

Assessing enrollment of eligible infants in the national pediatric cardiology quality improvement collaborative (NPC-QIC) through linkage to the pediatric cardiac critical care consortium (PC4) registry.

BACKGROUND: The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) lacks a rigorous enrollment audit process, unlike other collaborative networks. Most centers require individual families to consent to participate. It is unknown whether there is variation across centers or biases in enrollment. METHODS: We used the Pediatric Cardiac Critical Care Consortium (PC4) registry to assess enrollment rates in NPC-QIC for those centers participating in both registries using indirect identifiers (date of birth, date of admission, gender, and center) to match patient records. All infants born 1/1/2018-12/31/2020 and admitted 30 days of life were eligible. In PC4, all infants with a fundamental diagnosis of hypoplastic left heart or variant or who underwent a surgical or hybrid Norwood or variant were eligible. Standard descriptive statistics were used to describe the cohort and center match rates were plotted on a funnel chart. RESULTS: Of 898 eligible NPC-QIC patients, 841 were linked to 1,114 eligible PC4 patients (match rate 75.5%) in 32 centers. Match rates were lower in patients of Hispanic/Latino ethnicity (66.1%, p = 0.005), and those with any specified chromosomal abnormality (57.4%, p = 0.002), noncardiac abnormality (67.8%, p = 0.005), or any specified syndrome (66.5%, p = 0.001). Match rates were lower for patients who transferred to another hospital or died prior to discharge. Match rates varied from 0 to 100% across centers. CONCLUSIONS: It is feasible to match patients between the NPC-QIC and PC4 registries. Variation in match rates suggests opportunities for improvement in NPC-QIC patient enrollment.

Magnetic resonance three-dimensional steady-state free precession imaging of the thoracic duct in patients with Fontan circulation and its relationship to outcomes.

BACKGROUND: Lymphatic complications are common in patients with Fontan circulation. Three-dimensional balanced steady-state free precession (3D bSSFP) angiography by cardiovascular magnetic resonance (CMR) is widely used for cardiovascular anatomical assessment. We sought to determine the frequency of thoracic duct (TD) visualization using 3D bSSFP images and assess whether TD characteristics are associated with clinical outcomes. METHODS: This was a retrospective, single-center study of patients with Fontan circulation who underwent CMR. Frequency matching of age at CMR was used to construct a comparison group of patients with repaired tetralogy of Fallot (rTOF). TD characteristics included maximum diameter and a qualitative assessment of tortuosity. Clinical outcomes included protein-losing enteropathy (PLE), plastic bronchitis, listing for heart transplantation, and death. A composite outcome was defined as presence of any of these events. RESULTS: The study included 189 Fontan patients (median age 16.1 years, IQR 11.0-23.2 years) and 36 rTOF patients (median age 15.7 years, IQR 11.1-23.7 years). The TD diameter was larger (median 2.50 vs. 1.95 mm, p = 0.002) and more often well visualized (65% vs. 22%, p < 0.001) in Fontan patients vs. rTOF patients. TD dimension increased mildly with age in Fontan patients, R = 0.19, p = 0.01. In Fontan patients, the TD diameter was larger in those with PLE vs. without PLE (age-adjusted mean 4.11 vs. 2.72, p = 0.005), and was more tortuous in those with NYHA class ≥ II vs. class I (moderate or greater tortuosity 75% vs. 28.5%, p = 0.02). Larger TD diameter was associated with a lower ventricular ejection fraction that was independent of age (partial correlation = - 0.22, p = 0.02). More tortuous TDs had a higher end-systolic volume (mean 70.0 mL/m2 vs. 57.3 mL/m2, p = 0.03), lower creatinine (mean 0.61 mg/dL vs. 0.70 mg/dL, p = 0.04), and a higher absolute lymphocyte count (mean 1.80 K cells/µL vs. 0.76 K cells/µL, p = 0.003). The composite outcome was present in 6% of Fontan patients and was not associated with TD diameter (p = 0.50) or tortuosity (p = 0.09). CONCLUSIONS: The TD is well visualized in two-thirds of patients with Fontan circulation on 3D-bSSFP images. Larger TD diameter is associated with PLE and increased TD tortuosity is associated with an NYHA class ≥ II.

Predicting Cardiac Anatomy, Physiology, and Surgical Management Based on Fetal Echocardiography in Heterotaxy Syndrome.

OBJECTIVE: Heterotaxy syndrome (HS) is often associated with complex congenital heart disease (CHD). While fetal echocardiography (FE) permits accurate prenatal identification of most CHD, the high level of disease complexity in HS may pose challenges in predicting postnatal findings and outcomes. This study aimed to define the accuracy of FE in predicting postnatal anatomy, physiology, and surgical management of CHD in the setting of HS. STUDY DESIGN: Retrospective single-center cohort study including all patients with a prenatal diagnosis of HS from 2003 to 2018. Anatomic diagnoses from FE reports were compared with postnatal echocardiogram, catheterization, and operative reports. Prenatal predictions were compared with postnatal outcomes with a focus on ductal dependence, time to first intervention (immediate, neonatal period, 1-6 months, or older than 6 months), and surgical approach (single or biventricular). RESULTS: There were 102 pregnancies with fetal HS resulting in 21 terminations, 5 fetal losses, and 76 live births. Of the live births, 55 had significant CHD and available postnatal data for review. Among this group, survival to 1 year was 62% and was no different comparing single versus biventricular surgical approach. FE diagnostic accuracy varied by anatomic feature and was the lowest for diagnosis of venous anatomy. Determination of postnatal care was most accurate for predicting single versus biventricular surgical approach (91%), followed by ductal dependence (75%). Accuracy for predicting time to first intervention was the lowest at 69%. The most common reason for an incorrect prediction was difficulty in assessing the severity of pulmonary stenosis. CONCLUSION: FE permits accurate predictions regarding surgical approach. Characterizing systemic and pulmonary veins is challenging, as is predicting ductal dependence and time to first intervention. These data suggest that despite the high diagnostic accuracy of CHD in HS, a circumspect approach may be reasonable with regard to predicting some anatomic details and postnatal management decisions. KEY POINTS: · In HS, FE was most accurate for intracardiac anatomy.. · Diagnostic accuracy of venous anatomy was less reliable.. · Predicting surgical approach (single ventricle vs. biventricular) was highly accurate.. · Predicting ductal dependence and time-to-intervention were more challenging in some instances..

Screening and diagnostic imaging at centres performing congenital heart surgery in middle-income countries.

BACKGROUND: Surgical care for CHD is increasingly available in low- and middle-income countries, and efforts to optimise outcomes are growing. This study characterises cardiac imaging and prenatal diagnosis infrastructure in this setting. METHODS: An infrastructure survey was administered to sites participating in the International Quality Improvement Collaborative for CHD. Questions regarding transthoracic, transesophageal and epicardial echocardiography, cardiac CT, cardiac magnetic resonance, prenatal screening and fetal echocardiography were included. Associations with in-hospital and 30-day mortality were assessed. RESULTS: Thirty-seven sites in 17 countries responded. Programme size and geography varied considerably: < 250 cases (n = 13), 250-500 cases (n = 9), > 500 cases (n = 15); Americas (n = 13), Asia (n = 18), and Eastern Europe (n = 6). All had access to transthoracic echo. Most reported transesophageal and epicardial echocardiography availability (86 and 89%, respectively). Most (81%) had cardiac CT, but only 54% had cardiac magnetic resonance. A third reported impediments to imaging, including lack of portable machines, age/size-appropriate equipment and advanced cardiac imaging access and training. Only 19% of centres reported universal prenatal CHD screening in their catchment area, and only 46% always performed fetal echocardiography if screening raised concern for CHD. No statistically significant associations were identified between imaging modality availability and surgical outcomes. CONCLUSIONS: Although access to echocardiography is available in most middle-income countries; advanced imaging modalities (cardiac CT and magnetic resonance) are not always accessible. Prenatal screening for CHD is low, and availability of fetal echocardiography is limited. Imaging infrastructure in low- and middle-income countries and associations with outcomes merits additional study.

Current State of Fetal Heart Disease Counseling and Training: Room for Improvement? : Endorsed by the Fetal Heart Society.

We sought to describe the fellowship experiences and current practice habits of pediatric cardiologists who counsel patients with fetal heart disease (FHD) and to identify fellowship experiences related to FHD counseling perceived as valuable by respondents as well as opportunities for improvement. A cross-sectional survey of attending pediatric cardiologists who care for patients with FHD was performed. The respondents' demographics, fellowship experiences related to FHD counseling, reflections on fellowship training, and current practice habits were collected. The Fetal Heart Society endorsed this survey. There were 164 survey responses. 56% of respondents did not have 4th-year subspecialty training in fetal cardiology. Observing and performing FHD counseling were the most commonly used methods of training, with the highest perceived effectiveness. The number of counseling sessions observed and performed correlated moderately with confidence in FHD counseling skills at fellowship graduation. Extracardiac pathology and neurodevelopment were the least frequently addressed topics in fellowship training and in current practice. Fewer than 50% of respondents received formal education and feedback in counseling techniques during fellowship training. A significant proportion of practicing pediatric cardiologists provide FHD counseling with only standard categorical training. This highlights the potential importance of expanding FHD counseling education into categorical fellowship curricula. We suggest increasing opportunities for fellows to perform FHD counseling and receive feedback as this is a valued and beneficial experience during training. A formalized curriculum including extracardiac pathology and neurodevelopment and the use of evidence-based workshops in counseling techniques may address identified gaps in fellowship education.

The multisystem nature of isomerism: left isomerism complicated by Abernethy malformation and portopulmonary hypertension.

Isomerism, also referred to as "heterotaxy" is a complex set of anatomic and functional perturbations. One of the most obvious manifestations of isomerism is the disturbance of organ arrangement, such that the thoracic organs are no longer asymmetric on the left and right. We report the case of a 14-year-old female in whom exercise-induced dyspnea led to a late diagnosis of left isomerism complicated by Abernethy malformation and portopulmonary hypertension. A comprehensive evaluation revealed two anatomic left lungs and hyparterial bronchi, bilateral left atria, an interrupted inferior caval vein with azygos continuation, multiple spleens, sinus node dysfunction, hepatic hypertrophy with focal nodular hyperplasia, and absence of the portal vein. Pulmonary vasodilator therapy was initiated resulting in clinical improvement. This case exhibits unique features including a late diagnosis of isomerism with Abernethy malformation and portopulmonary hypertension. The patient's presentation, medical workup, and future treatment emphasise the importance of multidisciplinary care in children with complex multisystem disease. We review the multiple cardiac and extracardiac manifestations of isomerism.

Fetal acute cerebral vasoreactivity to maternal hyperoxia in low-risk pregnancies: a cross-sectional study.

OBJECTIVE: To establish whether fetal cerebral vasoreactivity (CVRO2 ), following maternal hyperoxia, is predicted by fetal cerebral and uteroplacental Doppler pulsatility indices (PI) at baseline, fetal pulmonary vasoreactivity to oxygen (PVRO2 ), gestational age (GA), or sex. METHODS: Pulsatility index of middle (MCA), anterior (ACA), posterior cerebral (PCA), umbilical (UA), uterine (UtA), and branch of the pulmonary arteries (PA) were obtained, by ultrasound, before (baseline), during (hyperoxia) and after 15 minutes of maternal administration of 8 L/min of 100% oxygen, through a non-rebreathing face mask, in normal singleton pregnancies within 20 to 38 weeks' gestation. CVRO2 was defined as changes greater than zero in z score of PI of the cerebral arteries from baseline to hyperoxia. Logistic modeling was applied to identify CVRO2 predictors. RESULTS: A total of 97 pregnancies were eligible. In the overall population, median z scores of PI of MCA, ACA, and PCA did not differ between study phases. Based on the logistic model, baseline z scores for cerebral PI and GA were the best predictors of CVRO2 . CONCLUSIONS: In low-risk pregnancies, fetal CVRO2 to hyperoxia does not occur uniformly but depends on cerebral PI and GA at baseline. These findings may provide useful reference points when oxygen is administered in high-risk pregnancies.

Durable Benefit of Particle Occlusion of Systemic to Pulmonary Collaterals in Select Patients After Superior Cavopulmonary Connection.

Systemic to pulmonary arterial collaterals (SPC) are commonly found in patients undergoing staged operative palliation for single ventricle heart disease. Occlusion of SPC as part of pre-Fontan catheterization has been shown to improve hemodynamics acutely. Anecdotally, the effect of this intervention appears to be transient, and to our knowledge there is no data supporting its durability in these patients. Between 1/1/2016 and 5/1/2017, 24 children underwent Glenn operations at our institution. Of these, 3 patients had signs and symptoms deteriorating clinical status suggestive of volume overload in the period between their Glenn operation and Fontan completion, prompting heart catheterization. SPC were occluded with a combination of polyvinyl alcohol embolization particles, and in some cases coils or vascular plugs. Clinical course and data from echocardiograms and serial catheterizations are presented. SPC occlusion was performed over 6 procedures in 3 subjects with technical success in each case. Hemodynamic evaluation was repeated in 2/3 patients with improvement in collateral burden and hemodynamics in both cases. One patient previously thought to be unsuitable for Fontan completion improved sufficiently to undergo late Fontan completion, which was ultimately successful. In all patients, there was improvement in clinical status. In patients with severe SPC collateral durable benefit was seen, suggesting that in certain cases intervention on SPC remote from Fontan completion may have clinical benefit.

Prenatal Maternal Hyperoxygenation Testing and Implications for Critical Care Delivery Planning among Fetuses with Congenital Heart Disease: Early Experience.

BACKGROUND: Maternal hyperoxygenation (MH) during fetal ultrasound can characterize fetal pulmonary vasoreactivity (PVr) and its associations with postnatal physiology. OBJECTIVE: We explored MH testing to facilitate perinatal risk stratification for fetuses with congenital heart disease (CHD). METHODS: MH was performed in 12 fetuses: 2 with Ebstein anomaly, 2 with total anomalous pulmonary venous connection (TAPVC), 4 with hypoplastic left heart syndrome (HLHS) with (a) restrictive atrial septum (RAS) or (b) intact atrial septum (IAS) with decompressing vertical vein (VV), and 4 with D-loop transposition of the great arteries (TGA). PVr and physiologic and anatomic changes with MH and outcomes were recorded. RESULTS: Among Ebstein fetuses, pulmonary blood flow with MH mirrored postnatal findings. Among TAPVC fetuses, MH VV gradients correlated with postnatal gradients. One HLHS/IAS/VV fetus had no PVr and decreased pulmonary vein forward to reverse velocity time integral ratio with MH. Shortly after delivery, the infant experienced severe low cardiac output and required urgent atrial septoplasty. The remaining HLHS fetuses had PVr and underwent routine Stage 1 Norwood. Among TGA fetuses, septum primum position, foramen ovale flow, and the presence or absence of PVr with MH reflected postnatal findings. CONCLUSION: MH may help identify fetuses with CHD at risk for perinatal compromise. Additional study may yield insights into fetal PVr and elucidate predictors of perinatal outcomes.

Fetal interventions for structural heart disease.

Fetal cardiac intervention (FCI) offers the potential to alter in utero anatomy and physiology. For aortic stenosis with evolving hypoplastic left heart syndrome and pulmonary atresia with intact ventricular septum with evolving hypoplastic right heart syndrome, FCI may result in maintenance of a biventricular circulation, thus avoiding single-ventricle palliation and its attendant complications. In the case of hypoplastic left heart syndrome with intact atrial septum, FCI may ameliorate in utero pathophysiology and portend a more favorable postnatal prognosis. In all cases, a detailed fetal echocardiographic assessment to identify the appropriate FCI candidate is essential. This article reviews the three aforementioned lesions for which FCI can be considered. The pathophysiology and rationale for intervention, echocardiographic assessment, patient selection criteria, and outcomes for each lesion will be reviewed. A primary focus will be the echocardiographic evaluation of each lesion.

Common Findings in Late-Gestation Fetal Echocardiography.

OBJECTIVES: Fetal echocardiography provides detailed information about cardiac structure and function in utero. Limited information is available regarding normal findings late in pregnancy. We therefore sought to identify and describe common cardiac findings in late gestation. METHODS: Fetuses with structurally normal hearts were identified in mid gestation within a subset of pregnant women in a prospective study. The atrioventricular valves, right and left atria, aortic isthmus and ductus arteriosus dimensions and flow abnormalities, aneurysm of the septum primum, and presence and grade of tricuspid regurgitation were assessed throughout pregnancy. Linear and logistic regression analyses were used to characterize changes in quantitative and qualitative fetal echocardiographic parameters by gestational age (GA). RESULTS: Forty fetuses between 24 and 38 weeks' GA were studied. Each had a fetal echocardiographic study completed before and after 34 weeks' gestation, which were compared. Tricuspid-to-mitral valve and right-to-left atrium ratios increased with GA (P < .001). More frequently noted after 34 weeks were tapering of the ductus arteriosus (2.5% versus 32%), prominent aortic isthmus diastolic flow (5% versus 67%), prominent ductus arteriosus diastolic flow (2.5% versus 25%), trivial or mild tricuspid regurgitation (35% versus 80%), and aneurysms of the septum primum (37.5% versus 80%). These findings all increased linearly with GA (P < .001). CONCLUSIONS: Atrioventricular valve and right/left atrium disproportion, mild ductus arteriosus tapering, prominent aortic isthmus and ductus arteriosus diastolic flow, trivial or mild tricuspid regurgitation, and aneurysms of the septum primum are frequently identified after 34 weeks' GA. Their identification suggests that these fetal echocardiographic findings in isolation are likely normal and are results of the physiologic alterations that occur late in the third trimester.

A Pediatric Cardiology Fellowship Boot Camp improves trainee confidence.

Introduction New paediatric cardiology trainees are required to rapidly assimilate knowledge and gain clinical skills to which they have limited or no exposure during residency. The Pediatric Cardiology Fellowship Boot Camp (PCBC) at Boston Children's Hospital was designed to provide incoming fellows with an intensive exposure to congenital cardiac pathology and a broad overview of major areas of paediatric cardiology practice. METHODS: The PCBC curriculum was designed by core faculty in cardiac pathology, echocardiography, electrophysiology, interventional cardiology, exercise physiology, and cardiac intensive care. Individual faculty contributed learning objectives, which were refined by fellowship directors and used to build a programme of didactics, hands-on/simulation-based activities, and self-guided learning opportunities. RESULTS: A total of 16 incoming fellows participated in the 4-week boot camp, with no concurrent clinical responsibilities, over 2 years. On the basis of pre- and post-PCBC surveys, 80% of trainees strongly agreed that they felt more prepared for clinical responsibilities, and a similar percentage felt that PCBC should be offered to future incoming fellows. Fellows showed significant increase in their confidence in all specific knowledge and skills related to the learning objectives. Fellows rated hands-on learning experiences and simulation-based exercises most highly. CONCLUSIONS: We describe a novel 4-week-long boot camp designed to expose incoming paediatric cardiology fellows to the broad spectrum of knowledge and skills required for the practice of paediatric cardiology. The experience increased trainee confidence and sense of preparedness to begin fellowship-related responsibilities. Given that highly interactive activities were rated most highly, boot camps in paediatric cardiology should strongly emphasise these elements.

Site of interstage care, resource utilization, and interstage mortality: a report from the NPC-QIC registry.

Morbidity and mortality remain high for patients with hypoplastic left heart syndrome during the interstage period between Norwood and Glenn despite ongoing QI efforts. We sought to identify associations between the site of interstage care, interstage events, and mortality. Data for patients enrolled in the National Pediatric Cardiology Quality Improvement Collaborative registry from July 2008 through February 2013 were reviewed. Patients had outpatient interstage care at (1) the surgical site (SS) performing Norwood, (2) a non-surgical site (NSS), or (3) a combination. Interstage events were compared among these groups and, when applicable, by distance from SS to NSS. 688 patients from 47 sites met entry criteria. Patients were followed at the SS 411 (60%), NSS 121 (17%), or a combination 143 (21%). Data were not available for 13 (2%). There were 66 deaths (10%) among the entire cohort: 37 (9%) at SS, 13 (11%) at NSS, 15 (10%) at a combination. The proportion of deaths among these groups was not statistically significant (p = 0.60), nor was there a difference based on SS-to-NSS distance. Patients followed at the SS were more likely to have problems detected with feeding (p = 0.03) and breathing (p = 0.002), and ED visits (p < 0.001). The site of interstage care was not associated with mortality, nor was there a difference based on SS-to-NSS distance. Patients followed at the SS had more detected breathing and feeding problems, and ED visits. Further study is required to elucidate the clinical significance of these differences.

Site of interstage outpatient care and growth after the Norwood operation.

BACKGROUND: Recent efforts have focused on optimising interstage outcomes, including growth, for infants following the Norwood operation. The impact of the site of interstage care remains unclear, and it has been hypothesised that care at the surgical site may be beneficial due to greater access to resources such as nutritional support. This study evaluated the relationship between site of interstage care and weight gain in a large multicentre cohort. METHODS: Infants enrolled in the National Paediatric Cardiology Quality Improvement Collaborative (2008-2013) surviving up to Stage 2 were included. Change in weight-for-age z-score between Norwood discharge and Stage 2 admission was compared in those receiving care at the surgical versus non-surgical site. RESULTS: Of the 487 interstage survivors, 60% received all care at the surgical site, and 40% received care at a non-surgical site. There was no significant difference between groups in change in weight-for-age z-score: +0.36±0.96 for the surgical site group versus +0.46±1.02 for the non-surgical site group, p=0.3. Results were unchanged in multivariable analysis adjusting for differences in important baseline characteristics, duration of interstage, and home surveillance strategy. The proportion of all patients with weight-for-age z-score <-2 decreased from 40% at Norwood discharge to 29% at Stage 2, with no significant difference in change between the two groups (p=0.1). CONCLUSIONS: The site of interstage care was not associated with weight gain during the interstage period. Nearly one-third of patients overall had a weight-for-age z-score <-2 at Stage 2. Further study is required to identify methods to optimise weight gain in these patients.

Percutaneous fetal cardiac interventions for structural heart disease.

INTRODUCTION: Prenatal diagnosis provides valuable information regarding a variety of congenital heart defects. Some defects occur early in gestation with little change throughout pregnancy, whereas others evolve during mid and late gestation. Fetal cardiac intervention (FCI) affords the opportunity to interrupt progression of disease in this latter category, resulting in improved perinatal and lifelong outcomes. AIM: This chapter addresses three lesions for which percutaneous FCI can be utilized: (1) aortic stenosis with evolving hypoplastic left heart syndrome, for which aortic valvuloplasty may prevent left ventricular hypoplasia and has yielded a biventricular circulation in approximately one third of cases; (2) hypoplastic left heart syndrome with intact atrial septum, for which relief of atrial restriction has potential to improve perinatal survival; and (3) pulmonary atresia with intact ventricular septum and evolving right ventricular hypoplasia, for which pulmonary valvuloplasty has resulted in a biventricular circulation in the majority of patients. The pathophysiology, rationale for intervention, patient selection criteria, procedural technique, and outcomes for each lesion will be reviewed. This chapter will also review complications of FCI and their treatment, and maternal and fetal anesthesia specific to FCI. The importance of a specialized center with experience managing infants delivered after FCI will also be addressed.

Congenital Heart Disease Illustrated: Use of Cross-sectional Imaging in Pediatric Cardiology.

In the modern era of cardiac imaging, there is increasing use of cardiac computed tomography and cardiac magnetic resonance for visualization of congenital heart disease (CHD). Advanced visualization techniques such as virtual dissection, 3-dimensional modeling, and 4-dimensional flow are also commonly used in clinical practice. This review highlights such methods in five common forms of CHD, including double outlet right ventricle, common arterial trunk, sinus venosus defects, Tetralogy of Fallot variants, and heterotaxy, providing visualizations of pathology in both conventional and novel formats.

The impact of audiovisual breathing guidance on respiratory-triggered cardiac magnetic resonance cine imaging.

BACKGROUND: In patients who have difficulty holding their breath, a free breathing (FB) respiratory-triggered (RT) bSSFP cine technique may be used. However, this technique may have inferior image quality and a longer scan time than breath-hold (BH) bSSFP cine acquisitions. This study examined the effect of an audiovisual breathing guidance (BG) system on RT bSSFP cine image quality, scan time, and ventricular measurements. METHODS: This study evaluated a BG system that provides audiovisual instructions and feedback on the timing of inspiration and expiration to the patient during image acquisition using input from the respiratory bellows to guide them toward a regular breathing pattern with extended end-expiration. In this single-center prospective study in patients undergoing a clinical cardiac magnetic resonance examination, a ventricular short-axis stack of bSSFP cine images was acquired using 3 techniques in each patient: 1) FB and RT (FBRT), 2) BG system and RT (BGRT), and 3) BH. The 3 acquisitions were compared for image quality metrics (endocardial edge definition, motion artifact, and blood-to-myocardial contrast) scored on a Likert scale, scan time, and ventricular volumes and mass. RESULTS: Thirty-two patients (19 females; median age 21 years, IQR 18-32) completed the study protocol. For scan time, BGRT was faster than FBRT (163 s vs. 345 s, p < 0.001). Endocardial edge definition, motion artifact, and blood-to-myocardial contrast were all better for BGRT than FBRT (p < 0.001). Left ventricular (LV) end-systolic volume (ESV) was smaller (3%, p = 0.02) and LV ejection fraction (EF) was larger (0.5%, p = 0.003) with BGRT than with FBRT. There was no significant difference in LV end-diastolic volume (EDV), LV mass, right ventricular (RV) EDV, RV ESV, and RV EF. Scan times were shorter for BGRT compared to BH. Endocardial edge definition and blood-to-myocardial contrast were better for BH than BGRT. Compared to BH, the LV EDV, LV ESV, RV EDV, and RV ESV were mildly smaller (all differences <7%) for BGRT. CONCLUSIONS: The addition of a BG system to RT bSSFP cine acquisitions decreased the scan time and improved image quality. Further exploration of this BG approach is warranted in more diverse populations and with other free breathing sequences.