Novel application of the Diabolo technique to restrict pulmonary blood flow in a single ventricle patient with a right ventricle to pulmonary artery conduit

Balancing pulmonary and systemic circulations in single ventricle patients with a conduit after Stage 1 palliation is challenging. A transcatheter intervention for excessive pulmonary blood flow would provide benefit. We report a case of a critically ill single ventricle patient with symptoms of excessive pulmonary blood flow after Stage 1 despite maximal medical therapy. The patient underwent percutaneous intraluminal downsizing of the right ventricle to pulmonary artery conduit using a novel application of the Diabolo-covered stent technique, with subsequent clinical improvement. A second catheterization was performed during the interstage period with successful dilation of the stent to achieve appropriate saturations. The Diabolo technique can be successfully employed in this population to restrict pulmonary blood flow and has the advantage of being adjusted during placement and in subsequent interventions.

Cardiac fibroma presenting as hypoplastic left heart syndrome in a foetus: causal or coincidental?

Primary cardiac tumours are very rare. Cardiac tumours in the perinatal period are even more uncommon with a prevalence of 0.0017% to 0.28% in autopsy series. The majority of benign cardiac tumours are cardiac rhabdomyomas, followed by cardiac fibromas. Another rare congenital heart disease is hypoplastic left heart syndrome (HLHS). Here we present a 21-week-old foetus diagnosed antenatally with HLHS on foetal echocardiogram. An autopsy done on the foetus following medical termination of pregnancy revealed a cardiac fibroma in the ventricular septum. It is very uncommon to have a combination of two congenital heart diseases. An extensive literature review revealed only three cases that had rhabdomyoma and associated HLHS. This case presented with cardiac fibroma which in early gestation would have resulted in left ventricular outflow obstruction leading to the development of HLHS. Small cardiac tumours which are difficult to detect by echocardiogram in early gestation can lead to the development of HLHS. A thorough and hierarchical autopsy examination of such cases can help in a better understanding of the relationship between HLHS and cardiac tumours.

Inpatient Resource Utilization for Hypoplastic Left Heart Syndrome from Birth Through Fontan

Completing 3-stage palliation for hypoplastic left heart syndrome requires significant resources. An analysis of recent data has not been performed. We aimed to determine total charges necessary to complete all 3 stages of single-ventricle palliation, including interstage encounters. We also aimed to determine overall resource utilization, including hospital days, interstage admissions, and interstage procedures. We performed a retrospective cohort study using data from the Pediatric Health Information System database between 2016 and 2021, including all patients who completed 3-stage palliation for hypoplastic left heart syndrome. We identified 199 patients who underwent 3-stage palliation of hypoplastic left heart syndrome between 2016 and 2021. Median total adjusted charges (interquartile range, IQR) over the course of 3-stage palliation were $1,475,800 ($1,028,900-2,191,700). Median adjusted charges (IQR) for stage 1, 2, and 3 hospitalizations were $604,300 ($419,000-891,400), $234,000 ($164,300-370,800), and $256,260 ($178,300-345,900), respectively. Median hospital length of stay (IQR) for stages 1, 2, and 3 was 36 (26,53), 9 (6,17), and 10 (7,14) days, respectively. Pulmonary artery stenosis was the most common admitting diagnosis for interstage hospitalizations (3.4% of hospitalizations). Cardiac catheterization (24.1% of procedures) and feeding tube placement (10.0% of procedures) were the most common principal procedures during interstage hospitalizations. Total inpatient charges incurred throughout 3-stage palliation of hypoplastic left heart syndrome are substantial and have risen since prior studies. Gastrointestinal comorbidities and feeding optimization contribute considerably to this resource utilization.

School age and adolescent heart failure following the Norwood procedure

BACKGROUND

Heart failure results in significant morbidity and mortality for young children with hypoplastic left heart syndrome (HLHS) following the Norwood procedure. The trajectory in later childhood is not well described.

METHODS

We studied the outcome into adolescence of participants enrolled in the Single Ventricle Reconstruction trial who underwent the Fontan procedure or survived to 6 years without having undergone Fontan procedure. The primary outcome was heart failure events, defined as heart transplant listing or death attributable to heart failure. Symptomatic heart failure for participants surviving 10 or more years was also assessed utilizing the Pediatric Quality of Life Inventory (PedsQL).

RESULTS

Of the 345 participants who underwent a Fontan operation or survived to 6 years without Fontan, 25 (7.2%) had a heart failure event before the age of 12 years. Among these, 21 were listed for heart transplant, and 4 died from heart failure. Nineteen participants underwent heart transplant, all of whom survived to age 12 years. Factors associated with a heart failure event included longer Norwood hospital length of stay, aortic atresia, and no Fontan operation by age 6 years. Assessment of heart failure symptoms at 12 years of age revealed that 24 (12.2%) of 196 PedsQL respondents "often" or "almost always" had difficulty walking more than one block.

CONCLUSIONS

Heart failure events occur in over 5% of children with palliated HLHS between preschool age and adolescence. Outcomes for children listed for transplant are excellent. However, a substantial portion of palliated HLHS children have significant symptoms of heart failure at 12 years of age.

Multimodality imaging for the diagnosis of left ventricular apical hypoplasia: A case presentation and review of the literatures

Left ventricular apical hypoplasia is a rare malformation recently described congenital abnormality characterized by: (1) truncation of the left ventricle, with the septum projecting toward the right ventricle; (2) abnormal papillary muscle originating from the flattened left ventricular apex; (3) a narrow right ventricle encompassing the periapical area of the left ventricle; (4) fatty infiltration of the apex of the left ventricle. We reported a case of LVAH and reviewed the patient's clinical presentation. And its morphologic characteristics were revealed by multimodality imaging, including echocardiography and cardiac magnetic resonance imaging. Additionally, we reviewed 41 cases from 32 reports to summarize the pathogenesis and analyzed the imaging manifestations of LVAH in this study, aiming to provide new ideas for the diagnosis and clinical management of LVAH patients.

Endovascular rehabilitation of acutely thrombosed fontan conduit in a patient with multiorgan failure

A 32-year-old man with history of hypoplastic left heart syndrome status post-Fontan palliation (20-mm aortic homograft conduit) had previously undergone Fontan conduit (FC) and left pulmonary artery (LPA) stenting to relieve conduit obstruction.

Hospitalisations of children and adults with Hypoplastic Left Heart Syndrome in Texas from 2009 to 2019

INTRODUCTION

Hypoplastic Left Heart Syndrome accounts for a significant proportion of CHD morbidity and mortality, despite improvements in care and improved survival. This study evaluates number of, reasons for, and trends in discharges of patients with hypoplastic left heart syndrome over 11 years in Texas.

METHODS

The Texas Inpatient Discharge Dataset Public Use File captures almost all discharges in Texas and was reviewed from 2009 to 2019. Discharges of patients ≥5 years of age and diagnosis codes for Hypoplastic Left Heart Syndrome were included. The admitting and principle diagnoses were categorised and all discharges were evaluated for procedures performed. Descriptive and univariate statistical analyses were performed.

RESULTS

A total of 1024 discharges were identified with a 16.9% annual increase over the study period. Median length of stay was 4 [IQR: 2-8] and there were 17 (1.7%) in-hospital mortalities with no differences across age groups. Seven (17.1%) discharges of patients 25+ years were uninsured, higher than other age groups (p < 0.001). The most common admitting diagnosis was CHD and 224 (21.9%) of discharges included a procedure, including 23 heart transplants. Discharges occurred from 67 different hospitals with 4 (6.0%) representing 71.4% of all discharges.

CONCLUSIONS

Discharges of Hypoplastic Left Heart Syndrome have increased rapidly, particularly in the older age groups and were spread over a large number of hospitals. Further work is needed to understand the interplay between Hypoplastic Left Heart Syndrome and other conditions and care experiences that occur within the general population, which will become more common as this population ages and grows.

Neighborhood Social Vulnerability and Interstage Weight Gain: Evaluating the Role of a Home Monitoring Program

Background Poor interstage weight gain is a risk factor for adverse outcomes in infants with hypoplastic left heart syndrome. We sought to examine the association of neighborhood social vulnerability and interstage weight gain and determine if this association is modified by enrollment in our institution's Infant Single Ventricle Management and Monitoring Program (ISVMP). Methods and Results We performed a retrospective single-center study of infants with hypoplastic left heart syndrome before (2007-2010) and after (2011-2020) introduction of the ISVMP. The primary outcome was interstage weight gain, and the secondary outcome was interstage growth failure. Multivariable linear and logistic regression models were used to examine the association between the Social Vulnerability Index and the outcomes. We introduced an interaction term into the models to test for effect modification by the ISVMP. We evaluated 217 ISVMP infants and 111 pre-ISVMP historical controls. The Social Vulnerability Index was associated with interstage growth failure (P=0.001); however, enrollment in the ISVMP strongly attenuated this association (P=0.04). Pre-ISVMP, as well as high- and middle-vulnerability infants gained 4 g/d less and were significantly more likely to experience growth failure than low-vulnerability infants (high versus low: adjusted odds ratio [aOR], 12.5 [95% CI, 2.5-62.2]; middle versus low: aOR, 7.8 [95% CI, 2.0-31.2]). After the introduction of the ISVMP, outcomes did not differ by Social Vulnerability Index tertile. Infants with middle and high Social Vulnerability Index scores who were enrolled in the ISVMP gained 4 g/d and 2 g/d more, respectively, than pre-ISVMP controls. Conclusions In infants with hypoplastic left heart syndrome, high social vulnerability is a risk factor for poor interstage weight gain. However, enrollment in the ISVMP significantly reduces growth disparities.

Milrinone for treatment of elevated lactate in the pre-operative newborn with hypoplastic left heart syndrome

BACKGROUND

There is a paucity of information reported regarding the use of milrinone in patients with hypoplastic left heart syndrome prior to the Norwood procedure. At our institution, milrinone is initiated in the pre-operative setting when over-circulation and elevated serum lactate levels develop. We aimed to review the responses associated with the administration of milrinone in the pre-operative hypoplastic left heart syndrome patient. Second, we compared patients who received high- versus low-dose milrinone prior to Norwood procedure.

METHODS

Single-centre retrospective study of patients diagnosed with hypoplastic left heart syndrome between January 2000 and December 2019 who underwent Norwood procedure. Patient characteristics and outcomes were compared.

RESULTS

During the study period, 375 patients were identified; 79 (21%) received milrinone prior to the Norwood procedure with median lactate 2.55 mmol/l, and SpO2 93%. Patients who received milrinone were older at the time of Norwood procedure (6 vs. 5 days) and were more likely to be intubated and sedated. In a subset analysis stratifying patients to low- versus high-dose milrinone, median lactate decreased from time of initiation (2.39 vs 2.75 to 1.6 vs 1.8 mmol/l) at 12 hours post-initiation, respectively. Repeated measures analysis showed a significant decrease in lactate levels by 4 hours following initiation of milrinone, that persisted over time, with no significant difference in mean arterial pressure.

CONCLUSIONS

The use of milrinone in the pre-operative over-circulated hypoplastic left heart syndrome patient is well tolerated, is associated with decreased lactate levels, and was not associated with significant hypotension or worsening of excess pulmonary blood flow.

New approach in stage 1 surgery for hypoplastic left heart syndrome: preliminary outcomes

OBJECTIVES

We present the short-term results of an alternative method in stage 1 surgery for hypoplastic left heart syndrome.

METHODS

Data of 16 consecutive patients who were treated with the novel method in our clinic between February 2019 and March 2021 were analysed retrospectively. Preoperative data and postoperative follow-up were recorded.

RESULTS

Of the 16 operated patients, 12 were diagnosed with hypoplastic left heart syndrome, while four were diagnosed with hypoplastic left heart syndrome variants. Seven patients died during early postoperative period. One patient died at home waiting stage 2 surgery. Three patient underwent stage 2 surgery. Pulmonary artery reconstruction was performed in one patient due to left pulmonary artery distortion.

CONCLUSIONS

We believe that our method can be an effective alternative in the surgery of hypoplastic left heart syndrome and its variants. It is hoped that with increasing number of studies and more experience better outcome will be achieved.

Use of extracorporeal membrane oxygenation and cerebral oximetry in a stage 1 norwood repair for hypoplastic left heart syndrome

The role of extracorporeal membrane oxygenation (ECMO) and its indications in stage I Norwood palliation are controversial. The decision to initiate ECMO and its timing remains difficult with no definitive cut-off points or evidence-based guidelines. It varies on a case-to-case basis. We report a case where the use of ECMO was beneficial after stage I Norwood palliation with severe ventricular dysfunction. The systemic-to-pulmonary artery shunt was kept open to balance the systemic and pulmonary circulations. Cerebral oximetry can be useful as an additional monitoring modality to guide management, monitor cerebral perfusion, and help detect cerebral steal.

Cardiovascular intensive care unit variables inform need for feeding tube utilization in infants with hypoplastic left heart syndrome

OBJECTIVE

Feeding strategies in infants with hypoplastic left heart syndrome (HLHS) following stage 1 palliation (S1P) include feeding tube utilization (FTU). Timely identification of infants who will fail oral feeding could mitigate morbidity in this vulnerable population. We aimed to develop a novel clinical risk prediction score for FTU.

METHODS

This was a retrospective study of infants with HLHS admitted to the Boston Children's Hospital cardiovascular intensive care unit for S1P from 2009 to 2019. Infants discharged with feeding tubes were compared with those on full oral feeds. Variables from early (birth to surgery), mid (postsurgery to cardiovascular intensive care unit transfer), and late (inpatient transfer to discharge) hospitalization were analyzed in univariate and multivariable models.

RESULTS

Of 180 infants, 66 (36.7%) discharged with a feeding tube. In univariate analyses, presence of a genetic disorder (early variable, odds ratio, 3.25; P = .014) and nearly all mid and late variables were associated with FTU. In the mid multivariable model, abnormal head imaging, ventilation duration, and vocal cord dysfunction were independent predictors of FTU (c-statistic 0.87). Addition of late variables minimally improved the model (c-statistic 0.91). A risk score (the HV2 score) for FTU was developed based on the mid multivariable model with high specificity (93%).

CONCLUSIONS

Abnormal head imaging, duration of ventilation, and presence of vocal cord dysfunction were associated with FTU in infants with HLHS following S1P. The predictive HV2 risk score supports routine perioperative head imaging and vocal cord evaluation. Future application of the HV2 score may improve nutritional morbidity and hospital length of stay in this population.

Management of Hypoplastic Left Heart Syndrome in Low-Resource Settings and the Ethics of Decision-Making

Hypoplastic left heart syndrome (HLHS) is possibly the most challenging congenital heart defect to confront in any setting. The highly specialized infrastructure and resources needed to treat HLHS is not available in many low-resource settings. However, low-resource settings must not be assumed to be synonymous with low- and middle-income countries as national income is not necessarily indicative of a country's prioritization of healthcare resources. Besides, a low-resource setting may be institution-specific as well as country-specific. We have stratified institutional capabilities for addressing the requirements of treatment for HLHS into five levels based on the capacity for diagnosis, intervention, and post-discharge monitoring. Depending on institutional capabilities, children born with HLHS in low-resource settings experience a spectrum of outcomes ranging from death without diagnosis to the hybrid or Norwood stage 1 palliation. The decision-making is ethically challenging when resources are scarce and economic efficiency must be considered in the context of distributive justice. Even in settings that would be classified as resource-rich where survival after surgery and quality of life afterward keep improving, not every parent would choose surgical intervention for their hypothetical child with HLHS.

The perinatal transition and early neonatal period in hypoplastic left heart syndrome is associated with reduced systemic and cerebral perfusion

BACKGROUND

The impact of the striking perinatal circulatory changes on blood flow distribution have not to date been well-examined in hypoplastic left heart syndrome (HLHS). This study aims to document perinatal redistribution of cardiac output in HLHS compared to healthy controls, to further understand the impact of perinatal transition on cerebral and systemic blood flow.

METHODS

Prospectively recruited HLHS cases (n=31) and healthy controls (n=19) underwent serial echocardiography from late fetal stages to 96 hours after birth. Combined cardiac output (CCO), systemic, pulmonary, cerebrovascular and splanchnic flow data were compared between HLHS neonates and controls, and the impact of vasoactive support and positive pressure ventilation (PPV) in HLHS patients examined.

RESULTS

In late gestation, CCO was similar between HLHS and controls, whereas middle cerebral artery (MCA) pulsatility index (PI) in HLHS was consistent with low cerebral vascular resistance. In the 96 hours after birth, CCO and pulmonary blood flow progressively increased in HLHS compared to controls (p<0.001), and CCO was further increased in HLHS neonates receiving vasoactive support (p=0.01). HLHS neonates had reduced systemic and 6-24hr superior vena cava (SVC) flow when compared to controls (p<0.001). Low systemic flow was further suggested by increased MCA and celiac artery PI at 6 - 48 hours in HLHS neonates (p<0.001). Systemic and SVC flow did not differ between those with and without vasoactive support.

CONCLUSION

We provide quantitative echocardiographic evidence associating impaired cerebral and systemic blood flow with perinatal hemodynamic changes in the preoperative HLHS neonate.

Isolated ventricular apical hypoplasia: A report of four cases and literature review

Isolated ventricular apical hypoplasia (IVAH) is a rare congenital cardiac anomaly, with clinical manifestations depending on the age of the patient, ranging from no symptoms in children to congestive heart failure or even malignant tachycardia in adults. Herein, we describe the clinical and anatomical findings in four cases with hypoplasia of the right or left ventricular apex, and we discuss the possible mechanisms and differential diagnosis of this malformation. Echocardiography is a rapidly accessible, low cost, noninvasive technique for the detection and evaluation of IVAH.

Alternate Approach to Hypoplastic Left Heart Syndrome Stage 1 Surgery

Hypoplastic left heart syndrome is almost always fatal in neonates unless it is palliated surgically. The conventional Norwood procedure with a Blalock-Taussig shunt or a Sano modification and a hybrid approach with branch pulmonary artery banding and ductal stenting are common surgical options. An alternate technique with a different strategy to restore pulmonary blood flow is described in this report.

Autologous stem cell therapy for hypoplastic left heart syndrome: Safety and feasibility of intraoperative intramyocardial injections

OBJECTIVES

Staged surgical palliation for hypoplastic left heart syndrome results in an increased workload on the right ventricle serving as the systemic ventricle. Concerns for cardiac dysfunction and long-term heart failure have generated interest in first-in-infant, cell-based therapies as an additional surgical treatment modality.

METHODS

A phase 1 clinical trial was conducted to evaluate the safety and feasibility of direct intramyocardial injection of autologous umbilical cord blood-derived mononuclear cells in 10 infants with hypoplastic left heart syndrome at the time of stage II palliation.

RESULTS

All 10 patients underwent successful stage II palliation and intramyocardial injection of umbilical cord blood-derived mononuclear cells. Operative mortality was 0%. There was a single adverse event related to cell delivery: An injection site epicardial bleed that required simple oversew. The cohort did not demonstrate any significant safety concerns over 6 months. Additionally, the treatment group did not demonstrate any reduction in cardiac function in the context of the study related intramyocardial injections of autologous cells.

CONCLUSIONS

This phase 1 clinical trial showed that delivering autologous umbilical cord blood-derived mononuclear cells directly into the right ventricular myocardium during planned stage II surgical palliation for hypoplastic left heart syndrome was safe and feasible. Secondary findings of preservation of baseline right ventricular function throughout follow-up and normalized growth rates support the design of a phase 2b follow-up trial.

Innovative 2-Step Management Strategy Utilizing EXIT Procedure for a Fetus With Hypoplastic Left Heart Syndrome and Intact Atrial Septum

Hypoplastic left heart syndrome (HLHS) with intact atrial septum (HLHS-IAS) carries a high risk of mortality and affects about 6% of all patients with HLHS. Fetal interventions, postnatal transcatheter interventions, and postnatal surgical resection have all been used, but the mortality risk continues to be high in this subgroup of patients. We describe a novel, sequential approach to manage HLHS-IAS and progressive fetal hydrops. A 28-year-old, gravida 4 para 2 mother was referred to Mayo Clinic for fetal HLHS. Fetal echocardiography at 28 weeks of gestation demonstrated HLHS-IAS with progressive fetal hydrops. The atrial septum was thick and muscular with no interatrial communication. Ultrasound-guided fetal atrial septostomy was performed with successful creation of a small atrial communication. However, fetal echocardiogram at 33 weeks of gestation showed recurrence of a pleural effusion and restriction of the atrial septum. We proceeded with an Ex uteroIntrapartum Treatment (EXIT) delivery and open atrial septectomy. This was performed successfully, and the infant was stabilized in the intensive care unit. The infant required venoarterial extracorporeal membrane oxygenator support on day of life 1. The patient later developed hemorrhagic complications, leading to his demise on day of life 9. This is the first reported case of an EXIT procedure and open atrial septectomy performed without cardiopulmonary bypass for an open-heart operation and provides a promising alternative strategy for the management of HLHS-IAS in select cases.

The effect of prenatal diagnosis on antibiotic therapy in neonates with hypoplastic left heart syndrome. Antibiotics in prenatally diagnosed patients with HLHS

INTRODUCTION

Hypoplastic left heart syndrome (HLHS) is a congenital heart anomaly that is diagnosed prenatally or postnatally. The prenatal diagnosis leads to limiting the rate of systemic complications in the preoperative period due to optimization of the early therapeutic management.

OBJECTIVE

The objective of the study is to determine the effect of prenatal diagnostic management of HLHS on the condition of newborns and the frequency of antibiotherapy employment prior to the first stage of surgical treatment.

METHODOLOGY

The study included 95 children with HLHS operated on in the years 2014-2016. The cohort was divided into two groups: newborns with a prenatally diagnosed heart defect (50 children - 52.6%) and neonates with the defect diagnosed after birth (45 children - 47.4%). The data of the patients were analyzed based on their medical records.

RESULTS

The mean age of the children upon admission was 3.86 days in the group of patients with the prenatally diagnosed heart defect (PreHLHS) and 7.41 days in the group of newborns without the prenatal diagnosis (PostHLHS) (p = 0.001). In 60% of the PreHLHS group patients (30/50), at least one antibiotic was administered, while in the PostHLHS group, antibiotherapy was employed in 93.3% (42/45) cases (p = 0.001). Bacteriological tests demonstrated pathogen growth in 33 children (36% and 33.3%, respectively), what accounted for 34.7% of the entire cohort. On the average, the first antibiotic was introduced on the 6.55th day of life in the PreHLHS group and on the 2.73th day in the PostHLHS group (p = 0.005). The most profound differences in antibiotic employment involved aminoglycosides. The aforementioned type of antibiotic medications was administered to 6% of the children with the prenatal diagnosis and to 17.8% of the children diagnosed postnatally (p = 0.042).

CONCLUSIONS

Preoperative antibiotherapy in children with HLHS was employed more frequently than it would be indicated by microbiology tests results. Antibiotics were observed to be introduced more commonly and earlier in the newborns with the postnatally diagnosed congenital heart defect.

Percutaneous obliteration of left ventricular cavity to eliminate aortic regurgitation and presumed coronary steal in an infant with hypoplastic left heart syndrome

The phenomenon of coronary steal is well known in the setting of HLHS (Hypoplastic Left Heart Syndrome) early after the Classical Norwood Operation. We report a rare case of an infant with HLHS [Severe Aortic Stenosis (AS), Mitral Stenosis (MS) and small Left Ventricle (LV)], who developed aortic regurgitation and presumed coronary steal late after the Sano Modification of the Norwood Procedure. Coronary steal developed secondary to progressive aortic and mitral regurgitation and resulted in poor right ventricular function and severe tricuspid regurgitation. We describe a novel interventional approach for obliteration of the LV cavity by using hydrogel coils. LV obliteration eliminated the presumed steal and resulted in improvement in ventricular function, tricuspid regurgitation and clinical course.

Pulse oximetry as a screening tool for critical congenital heart defects in newborns

OBJECTIVE

To evaluate the effectiveness of pulse oximetry as a screening tool for critical congenital heart defects in newborns.

METHODS

This cross-sectional study was conducted at the neonatology department of the Children's Hospital and the Institute of Child Health, Lahore, Pakistan, from January to June 2016, and comprised neonates aged up to 07 days. Babies with a prenatal diagnosis of heart defects and those whose parents refused to give consent were excluded. Oxygen saturation of enrolled patients was measured in right index finger (pre-ductal) and in the left big toe (post-ductal) subsequently. Echocardiography was done on all the enrolled babies to confirm the diagnosis. SPSS 19 was used for data analysis.

RESULTS

Of the 145 babies initially enrolled, 138(95.2%) were included. The overall mean age of the babies was 2.17±1.62 days (range: <24 hours-07 days) whereas the mean birth weight was 2.95±0.47kg (range: <2.5->4kg). Babies with pre- and post-ductal oxygen saturation measurement difference of >3% showed a detection rate of 16(45.7%) for critical congenital heart defects. Sensitivity and specificity of this screening test was calculated to be 76.19% and 83.76%, respectively, while positive and negative predictive values were 45.71% and 95.15%, respectively.

CONCLUSIONS

The measurement of pre- and post-ductal oxygen saturation by pulse oximetry was an effective screening tool for the detection of critical congenital heart defects in newborns.

Fetal left-sided cardiac structural dimensions in left-sided congenital diaphragmatic hernia - association with severity and impact on postnatal outcomes

OBJECTIVES

Fetuses with congenital diaphragmatic hernia (CDH) demonstrate varying degrees of left heart hypoplasia. Our study assesses the relationship between fetal left-sided cardiac structural dimensions, lung size, percentage liver herniation, lung-to-head ratio, postnatal left-sided cardiac structural dimensions, and postnatal outcomes.

METHODS

We performed a retrospective cohort study of fetuses with left-sided CDH who had prenatal echocardiographic, ultrasound, and magnetic resonance imaging examinations at our institution between January 2007 and March 2015. Postnatal outcomes assessed include use of inhaled nitric oxide (iNO), use of extracorporeal membrane oxygenation, and death.

RESULTS

Fifty-two fetuses with isolated left-sided CDH were included. Multivariate logistic regression models indicated that smaller fetal aortic valve z-score was associated with postnatal use of iNO (p = 0.03). Fetal mitral valve z-score correlated with lung-to-head ratio (p = 0.04), postnatal mitral valve z-score correlated with percent liver herniation (p = 0.03), and postnatal left ventricular end-diastolic dimension z-score correlated with liver herniation <20% (p = 0.04).

CONCLUSION

We identified associations between smaller fetal left-sided cardiac structural dimensions and classic CDH indices. Smaller aortic valve z-score was associated with iNO use; however, left heart dimensions showed no association with extracorporeal membrane oxygenation or mortality. Further study into the impact of left-sided hypoplasia on outcomes in CDH is worthy of evaluation in a larger, prospective study. © 2017 John Wiley & Sons, Ltd.

The neurodevelopmental implications of hypoplastic left heart syndrome in the fetus

As survival after cardiac surgery continues to improve, an increasing number of patients with hypoplastic left heart syndrome are reaching school age and beyond, with growing recognition of the wide range of neurodevelopmental challenges many survivors face. Improvements in fetal detection rates, coupled with advances in fetal ultrasound and MRI imaging, are contributing to a growing body of evidence that abnormal brain architecture is in fact present before birth in hypoplastic left heart syndrome patients, rather than being solely attributable to postnatal factors. We present an overview of the contemporary data on neurodevelopmental outcomes in hypoplastic left heart syndrome, focussing on imaging techniques that are providing greater insight into the nature of disruptions to the fetal circulation, alterations in cerebral blood flow and substrate delivery, disordered brain development, and an increased potential for neurological injury. These susceptibilities are present before any intervention, and are almost certainly substantial contributors to adverse neurodevelopmental outcomes in later childhood. The task now is to determine which subgroups of patients with hypoplastic left heart syndrome are at particular risk of poor neurodevelopmental outcomes and how that risk might be modified. This will allow for more comprehensive counselling for carers, better-informed decision making before birth, and earlier, more tailored provision of neuroprotective strategies and developmental support in the postnatal period.

Perioperative Management of a Child with Hypoplastic Left Heart Syndrome of the Jehovah's Witness Faith Presenting for Hybrid Comprehensive Stage II Procedure

Over the years, there has been a growing recognition of the potential negative sequelae of allogeneic blood products on postoperative outcomes following cardiac surgery. In addition, followers of the Jehovah's Witness (JW) faith have a religious restriction against receiving blood or blood components. Advances in perioperative care, cardiopulmonary bypass (CPB), and surgical technique have minimized the need for allogeneic blood products. Specific blood conservation strategies include maximizing the preoperative hematocrit and coagulation function as well as intraoperative strategies, such as acute normovolemic hemodilution and adjustments of the technique of CPB. We report a 7-month-old patient whose parents were of the JW faith who underwent a comprehensive stage II procedure for hypoplastic left heart syndrome without exposure to blood or blood products during his hospital stay. Perioperative techniques for blood avoidance are discussed with emphasis on their application to infants undergoing surgery for congenital heart disease.

Pulmonary Valve Replacement With Balloon-Expandable Prosthesis Under Direct Vision: A Novel Therapeutic Approach

A 57-year-old woman with a history of pulmonary atresia with ventricular septal defect and hypoplastic pulmonary arteries was referred for a fifth redo sternotomy for right ventricular outflow conduit replacement. Traditional pulmonary valve replacement was aborted during the procedure because of heavy calcification, and the pulmonary valve was replaced with a SAPIEN XT stent valve under direct vision. We believe this is the first application of a balloon-expandable stent valve in the pulmonary valve position under direct vision. It provides a novel therapeutic approach to recurrent pulmonary valve dysfunction in adult congenital heart diseases.

Hybrid therapy for hypoplastic left heart syndrome: Myth, alternative, or standard?

OBJECTIVE

This retrospective study presents our operative results, mortality, and morbidity with regard to pulmonary artery growth and reinterventions on the pulmonary artery and aortic arch, including key features of our institutional standards for the 3-stage hybrid palliation of patients with hypoplastic left heart syndrome.

METHODS

Between June 1998 and February 2015, 182 patients with hypoplastic left heart structures underwent the Giessen hybrid stage I procedure. Among these, 126 patients with hypoplastic left heart syndrome who received a univentricular palliation or heart transplantation were included in the main analysis. Median age and body weight of patients at hybrid stage I were 6 days (0-237) and 3.2 kg (1.2-7), respectively. Comprehensive stage II operation was performed at 4.5 months (2.9-39.5), and Fontan completion was established at 33.7 months (21.1-108.2). Operative and interstage mortality, morbidity, growth and reinterventions on the pulmonary arteries, and long-term operative results of the aortic arch reconstruction were assessed.

RESULTS

Median follow-up time after Giessen hybrid stage I palliation was 4.6 years (0-16.8). Operative mortality at hybrid stage I, comprehensive stage II, and Fontan completion was 2.5%, 4.9%, and 0%, respectively. Cumulative interstage mortality was 14.2%. At 10 years, the probability of survival is 77.8%. Body weight (<2.5 kg) and aortic atresia had no significant impact on survival. McGoon ratio did not differ at comprehensive stage II and Fontan completion (P = .991). Freedom from pulmonary artery intervention was estimated to be 32.2% at 10 years. Aortic arch reinterventions were needed in 16.7% of patients; 2 reoperations on the aortic arch were necessary.

CONCLUSIONS

In view of the early results and long-term outcome, the hybrid approach has become an alternative to the conventional strategy to treat neonates with hypoplastic left heart syndrome and variants. Further refinements are warranted to decrease patient morbidity.

Older Age at Completion of Fontan Procedure Is Associated with Improved Percentage of Predicted Maximum Oxygen Uptake

We tested the hypothesis that later completion of the Fontan procedure is associated with improved exercise capacity in the current period of staged single-ventricle palliation. We performed a retrospective study, in Fontan patients, of exercise stress test data from April 2003 through March 2011. Patients were included if they had received staged palliations in accordance with current surgical strategy, defined as the performance of a superior cavopulmonary connection at ≤1 year of age, followed in subsequent years by Fontan completion. Patients with a pacemaker or respiratory exchange ratio <1 were excluded. Early and late Fontan groups were created on the basis of whether Fontan completion had been performed at <4 or ≥ 4 years of age. The primary predictor variable was age at Fontan completion, and the primary marker of exercise performance was the percentage of predicted maximum oxygen consumption. During the study period, 55 patients were identified (mean age, 11.7 ± 2.8 yr). Older age at Fontan completion correlated positively with higher percentages of predicted maximum oxygen consumption (R=0.286, P=0.034). Patients in whom Fontan completion was performed at ≥4 years of age had higher percentages of predicted maximum oxygen consumption than did those in whom completion was at <4 years of age (84.4 ± 21.5 vs 72.9 ± 18.1; P=0.041). Later Fontan completion might be associated with improved exercise capacity in patients palliated in accordance with contemporary surgical strategy.

[Mutation of the lamin A/C gene associated with left ventricular apical hypoplasia: a new phenotype for laminopathies?]

Isolated left ventricular (LV) apical hypoplasia is a rare anomaly characterized by a dysfunctioning, spherical left ventricle and elongated right ventricle wrapping around the deficient LV apex. The etiology is unknown; it is presumed to be a rare congenital developmental defect during partitioning of the ventricles, caused by an in-utero infection. We describe for the first time a case of isolated LV apical hypoplasia associated with lamin A/C gene mutation. Echocardiography showed a mildly dilated left ventricle with spherical configuration and impaired systolic function, and an elongated right ventricle wrapping around the deficient LV apex. Magnetic resonance imaging also identified fatty replacement of the LV apical myocardium. Late gadolinium enhancement imaging showed mid-wall fibrosis in the interventricular septum. Family screening by ECG and echocardiography failed to identify heart disease in the patient's family; however, the proband's father and daughter were found to carry the same mutation. This case report highlights the difficulties of a correct interpretation of genetic mutations in a single patient with cardiomyopathy. Indeed, the causative role of a mutation needs to be confirmed by co-segregation analysis. Although the etiology of LV apical hypoplasia remains unknown, the first hypothesis is an acquired process interfering with the early development of the heart, the new one is a genetic defect.

Cardiovascular magnetic resonance parameters associated with early transplant-free survival in children with small left hearts following conversion from a univentricular to biventricular circulation

BACKGROUND

We sought to identify cardiovascular magnetic resonance (CMR) parameters associated with successful univentricular to biventricular conversion in patients with small left hearts.

METHODS

Patients with small left heart structures and a univentricular circulation who underwent CMR prior to biventricular conversion were retrospectively identified and divided into 2 anatomic groups: 1) borderline hypoplastic left heart structures (BHLHS), and 2) right-dominant atrioventricular canal (RDAVC). The primary outcome variable was transplant-free survival with a biventricular circulation.

RESULTS

In the BHLHS group (n = 22), 16 patients (73%) survived with a biventricular circulation over a median follow-up of 40 months (4-84). Survival was associated with a larger CMR left ventricular (LV) end-diastolic volume (EDV) (p = 0.001), higher LV-to-right ventricle (RV) stroke volume ratio (p < 0.001), and higher mitral-to-tricuspid inflow ratio (p = 0.04). For predicting biventricular survival, the addition of CMR threshold values to echocardiographic LV EDV improved sensitivity from 75% to 93% while maintaining specificity at 100%. In the RDAVC group (n = 10), 9 patients (90%) survived with a biventricular circulation over a median follow-up of 29 months (3-51). The minimum CMR values were a LV EDV of 22 ml/m² and a LV-to-RV stroke volume ratio of 0.19.

CONCLUSIONS

In BHLHS patients, a larger LV EDV, LV-to-RV stroke volume ratio, and mitral-to-tricuspid inflow ratio were associated with successful biventricular conversion. The addition of CMR parameters to echocardiographic measurements improved the sensitivity for predicting successful conversion. In RDAVC patients, the high success rate precluded discriminant analysis, but a range of CMR parameters permitting biventricular conversion were identified.

Prophylactic peritoneal dialysis catheter does not decrease time to achieve a negative fluid balance after the Norwood procedure: a randomized controlled trial

OBJECTIVE

Infants and children who undergo cardiopulmonary bypass and cardiac surgery are at risk of postoperative fluid overload. Peritoneal dialysis catheter (PDC) and peritoneal dialysis are reported to be effective means of postoperative fluid management. We sought to test the hypothesis that PDC insertion in the operating room at the time of Norwood palliation would decrease the time to achieve a negative fluid balance in a group of neonates with hypoplastic left heart syndrome.

METHODS

A single center randomized controlled trial was performed. We randomized neonates with hypoplastic left heart syndrome to prophylactic PDC, with or without dialysis, or standard care (ie, no PDC).

RESULTS

Twenty-two neonates were included; 10 were randomized to PDC and 12 were randomized to standard care. The mean time to first postoperative negative fluid balance was 2.70 ± 1.06 days for the prophylactic PDC group and 2.67 ± 0.65 days for the standard care group (P = .93). There was no difference between the 2 groups in time to lactate ≤ 2 mmol/L, maximum vasoactive-inotrope score on postoperative days 2 to 5, time to sternal closure, time to first extubation, modified clinical outcome score, or hospital length of stay. Twenty-one patients (95%) survived to hospital discharge. Four patients randomized to prophylactic PDC had 1 or more serious adverse events compared with no patients in the standard care group (P = .03).

CONCLUSIONS

Prophylactic PDC, with or without dialysis, did not decrease the time to achieve a negative fluid balance after the Norwood procedure, did not alter physiological variables postoperatively, and was associated with more severe adverse events.

[Therapeutic results in children with hypoplastic left heart syndrome after Norwood procedure]

Hypoplastic left heart syndrome (HLHS) encompasses hypoplasia or atresia of the left ventricle, stenotic or artretic aortic and mitral valves and hypoplasia of the ascending aorta. The aim of the 1-st stage operation called the modified Norwood procedure is reconstruction of the systemic flow, providing an adequate pulmonary flow and relieving interatrial restriction. The aim of the study was the analysis of treatment results after the Norwood operation in children hospitalized at Cardiology and Cardiac Surgery Departments in the period of 2009-2012. The material consisted of 65 children (42 males, 23 females). The following factors were analyzed: the age on admission, general condition, pre-operative clinical course.

RESULTS

The mean age of children on admission was 4.4 ± 4.1 days and mean body weight--3.3 ± 0.5 kg. The general condition was good in the majority of patients (74%). The remaining children were found to have early symptoms of congestive heart failure (CHF). Cardiological and/or surgical interventions were necessary in 33 (50.8%) patients, among them three children required both procedures. In the majority of patients (n = 21, 32%), the main cause of intervention was re-coarctation of the neo-aortic isth- mus treated with balloon plasty and/ or stenting. In the early post-operative period, six children died due to CHF (n = 4) and infections (n = 2), while the remaining six children died due to various complications while waiting for the 2nd stage.

CONCLUSIONS

Despite the progress in diagnosis and treatment of children with HLHS the mortality is still high.

Staged palliation of hypoplastic left heart syndrome: trends in mortality, cost, and length of stay using a national database from 2000 through 2009

Staged surgical palliation has revolutionized the care of patients with hypoplastic left heart syndrome (HLHS), although the outcomes of survival and cost at a national level remain unclear. This study sought to evaluate (1) trends in HLHS surgical outcomes including in-hospital mortality, length of stay (LOS), and cost, and (2) patient and hospital risk factors associated with these outcomes. Hospitalizations for patients with HLHS, including stage I, II, and III palliations, were analyzed using the Kids' Inpatient Database from 2000 through 2009. Trends in mortality, LOS, and cost were analyzed and chi-squared tests were used to test association between categorical variables. Patient and hospital characteristics associated with death were analyzed using logistic regression and associations with LOS were analyzed using ordinary least squared regression. There were 16,923 hospital admissions in patients with HLHS of which 5,672 (34%) included surgical intervention. Total (3,201-5,102) and surgery-specific admissions (1,165-1,618) increased from 2000 to 2009. Mortality decreased 14% per year in stage III palliations (odds ratio [OR] 0.86; 95% confidence interval [CI]: 0.79-0.94) and 6% per year for stage I palliations (OR 0.94; 95% CI 0.90-0.99) but not for stage II palliations (OR 1.01; 95% CI; 0.89-1.14). Length of stay increased for stage I and II palliations; however, per-patient hospital cost decreased in 2009. In conclusion, recent decrease in per patient cost for staged surgical palliation for HLHS has correlated temporally with improved mortality.

Midterm survival of infants requiring postoperative extracorporeal membrane oxygenation after Norwood palliation

This study reports the mid-term survival for neonates undergoing extracorporeal membrane oxygenation (ECMO) after Norwood palliation at a single center. Limited data exist on the mid-term survival of patients undergoing ECMO after Norwood palliation. We reviewed our ECMO experience from July 1994 to October 2008 and compared two groups: patients who required ECMO after Norwood palliation and patients who underwent Norwood palliation without ECMO. We analyzed 30-day survival, survival to hospital discharge, and survival to most recent follow-up. One hundred sixty patients underwent Norwood palliation for hypoplastic left heart syndrome (HLHS) and its variants. A total of 32 patients (20%) required postoperative ECMO. Using Kaplan-Meier analysis, the predicted survival rates for Norwood/non-ECMO patients to 30 days, 1 year, and 3 years after the procedure are 87.6% (CI 79.5-91.5%), 62.5% (CI 54.3-71.0%), and 59.9% (CI 50.8-67.8%), respectively. Survival to 30 days, 1 year, and 3 years after Norwood was significantly decreased in Norwood/ ECMO patients, with predicted survival rates of 50.0% (CI 31.9-65.7%), 24.6% (CI 11.4-40.4), and 13.2% (CI 3.9-28.3%), respectively (p < 0.0001). Risk factors for hospital mortality included nonelective or emergency placement onto ECMO, longer duration of ECMO support, and the development of acute renal failure while on ECMO. Of the original Norwood/ECMO hospital survivors, only half of these patients survived a mean of nearly 4 years. ECMO after Norwood palliation is associated with significant mortality. Our data suggest that neonates who require ECMO after Norwood palliation are prone to continued attrition once discharged from the hospital.

Individualized approach in the management of patients with hypoplastic left heart syndrome (HLHS)

Over the past decade new variations on the "classic" first stage palliation (the Norwood/BT shunt) for patients with Hypoplastic Left Heart Syndrome have emerged and been vetted by the medical community. A "one size fits all" approach may not be adequate anymore. In this review, the optimal indications for the various palliative options (Norwood/BT shunt, Norwood/RV-PA conduit, Hybrid Stage I with or without ductal stenting, heart transplantation) are reviewed from a standpoint of the initial anatomy and physiology of the patient, letting it guide clinical management. Current knowledge useful for decision-making is also reviewed as objectively as possible.

Strategies to maintain biventricular circulation in patients with high-risk anatomy

Although hypoplasia of left heart structures presents with a spectrum of severity, management decisions are typically dichotomous: single-ventricle palliation or biventricular repair. Since the long-term outcomes of single-ventricle palliation are sub-optimal, strategies to aggressively pursue biventricular circulation in patients with borderline left heart structures have been developed. Recent strategies and surgical techniques to rehabilitate the left heart in patients with borderline left heart are described.

In favor of the Hybrid Stage 1 as the initial palliation for hypoplastic left heart syndrome

There are many reasons to consider using the Hybrid Stage 1 procedure as the initial palliation for hypoplastic left heart syndrome. It allows all options for treatment, including a delayed traditional approach, as well as a platform to evolve our overall approach to this challenging heart defect.

[Clinical and cardiac imaging characteristics of patients with left ventricular apical hypoplasia]

OBJECTIVE

To analyze the clinical and cardiac imaging characteristics of patients with left ventricular apical hypoplasia (LVAH).

METHODS

From January 2008 to January 2012, seven patients [3 male/4 female, age: 6 - 44 (19.9 ± 14.2) years] with LVAH were included in this cohort. Transthoracic echocardiogram was performed in all patients, cardiovascular MRI was performed in 3 patients and cardiovascular CT in another 2 patients. In addition, one LVAH patient underwent cardiac catheterization and angiography examination.

RESULTS

Four out of 7 patients complained chest discomfort. Precordial murmur was heard in 3 patients. Atrial fibrillation was evidenced by electrocardiogram in 3 patients. Left ventricular end-diastolic diameter [(57.9 ± 11.6) mm] increased while left ventricule (LV) longitudinal diameter reduced in all patients. Left ventricular systolic function was reduced in 2 patients and mean LVEF was (47.6 ± 17.2)%. The interventricular septum bulged towards the right, and the ventricular septum thickness was (7.3 ± 1.2) mm. The papillary muscles were dominant on the flattened LV anteroapical region. The right ventricle elongated and wrapped around the hypoplastic left ventricular apex, and the dimension of right ventricle was (19.7 ± 7.6) mm. Focal fat replacement of the left ventricular apical wall was evidenced in 5 patients underwent cardiovascular MRI or CT examinations.

CONCLUSIONS

Clinical symptoms are non-specific in LVAH patients. Truncated and spherical LV, abnormal origin of papillary muscles in the flattened LV anterior apex and an elongated right ventricle wrapping around the LV apex as well as focal fat replacement of the left ventricular apical wall are typical imaging characteristics of LVAH.

Reduced ascending aorta distensibility relates to adverse ventricular mechanics in patients with hypoplastic left heart syndrome: noninvasive study using wave intensity analysis

OBJECTIVE

To evaluate the aortic arch elastic properties and ventriculoarterial coupling efficiency in patients with single ventricle physiology, with and without a surgically reconstructed arch.

METHODS

We studied 21 children with single ventricle physiology after bidirectional superior cavopulmonary surgery: 10 with hypoplastic left heart syndrome, who underwent surgical arch reconstruction, and 11 with other types of single ventricle physiology but without arch reconstruction. All children underwent pre-Fontan magnetic resonance imaging. No patient exhibited aortic recoarctation. Data on aortic wave speed, aortic distensibility and wave intensity profiles were all extracted from the magnetic resonance imaging studies using an in-house-written plug-in for the Digital Imaging and Communications in Medicine viewer OsiriX.

RESULTS

Children with hypoplastic left heart syndrome had significantly greater wave speed (P = .002), and both stiffer (P = .004) and larger (P < .0001) ascending aortas than the patients with a nonreconstructed arch. Aortic distensibility was not influenced by ventricular stroke volume but depended on a combination of increased aortic diameter and abnormal wall mechanical properties. Those with hypoplastic left heart syndrome had a lower peak wave intensity and reduced energy carried by the forward compression and the forward expansion waves, even after correction for stroke volume, suggesting an abnormal systolic and diastolic function. Lower wave energy was associated with an increased aortic diameter.

CONCLUSIONS

Using a novel, noninvasive technique based on image analysis, we have demonstrated that aortic arch reconstruction in children with hypoplastic left heart syndrome is associated with reduced aortic distensibility and unfavorable ventricular-vascular coupling compared with those with single ventricle physiology without aortic arch reconstruction.

Subjective evaluation of right ventricular systolic function in hypoplastic left heart syndrome: how accurate is it?

Background

The geometry and heterogeneity of the right ventricle in hypoplastic left heart syndrome makes objective echocardiographic assessment of systolic function challenging. Consequently, subjective echocardiographic assessment of right ventricular (RV) function is still routinely undertaken. The aims of this study were to compare this with magnetic resonance imaging (MRI), investigate the impact of experience and training on the accuracy of subjective assessment, and critically analyze the role of echocardiography to detect impaired systolic function.

Methods

A retrospective analysis of prospectively acquired data was performed. Children with hypoplastic left heart syndrome underwent routine preoperative cardiac MRI and echocardiography under the same general anesthetic. Echocardiograms were reviewed, and members of the congenital heart disease team with differing echocardiography experience subjectively graded RV systolic function (good, moderate, or poor). This was compared with MRI-derived ejection fraction.

Results

Twenty-eight patients at different palliative stages were included. Twenty-eight observers were divided into five experience categories (congenital heart disease junior trainees to attending cardiologists). Median agreement was 47.6% (range, 31.4%–58.2%), with the lowest agreement among junior trainees and the highest among attending cardiologists. When used as a screening test for poor RV systolic function, the median sensitivity of echocardiography was 0.89 (range, 0.86–0.96), and median specificity was 0.45 (range, 0.26–0.55). The highest sensitivity was observed among junior trainees but with the lowest specificity. The highest specificity was observed among attending cardiologists (0.55).

Conclusions

Agreement between echocardiographic and MRI RV ejection fraction improves with experience but remains suboptimal. When used as a screening test for poor RV function, echocardiography is sensitive, but specificity is heavily influenced by operator experience.

Effect of endovascular stenting of right ventricle to pulmonary artery conduit stenosis in infants with hypoplastic left heart syndrome on stage II outcomes

There is growing awareness that the Norwood procedure with the Sano modification is prone to early right ventricular to pulmonary artery (RV-PA) conduit stenosis resulting in systemic oxygen desaturation, increased interstage morbidity, and death. We report our experience with endovascular stent placement for conduit stenosis and compare the outcomes at stage II surgery between stented and nonstented infants. The medical records of all patients with hypoplastic left heart syndrome who received an RV-PA conduit at Norwood palliation from May 2005 to January 2010 were reviewed. The preoperative anatomy, demographics, operative variables, and outcomes pertaining to the Norwood and subsequent stage II surgeries were obtained and compared between stented and nonstented infants. The pre- and post-stent oxygen saturation, stenosis location, type and number of stents implanted, concomitant interventions, procedure-related complications, and reinterventions were collected. Of the 66 infants who underwent the Norwood procedure with RV-PA conduit modification, 16 (24%) received stents. The anatomy, demographics, and outcome variables after the Norwood procedure were similar between the stented and nonstented infants. The age at catheterization was 93 ± 48 days, and the weight was 4.9 ± 1.2 kg. The oxygen saturation increased from 66 ± 9% before intervention to 82 ± 6% immediately after stenting (p <0.0001). No interstage surgical shunt revisions were performed in either group. Age, weight, pre-stage II echocardiographic variables, oxygen saturation, and operative and outcome variables, including mortality, were similar between the 2 groups. In conclusion, endovascular stent placement for RV-PA conduit stenosis after the Norwood procedure leads to improved systemic oxygen levels and prevents early performance of stage II surgery without compromising stage II outcomes.

Relation of systemic-to-pulmonary artery collateral flow in single ventricle physiology to palliative stage and clinical status

Systemic-to-pulmonary collateral arteries (SPCs) are common in patients with single-ventricle physiology, but their impact on clinical outcomes is unclear. The aim of this study was to use retrospective cardiac magnetic resonance data to determine the relation between SPC flow and palliative stage and clinical status in single-ventricle physiology. Of 116 patients, 78 were after Fontan operation (median age 19 years) and 38 were at an earlier palliative stage (median age 2 years). SPC flow was quantified as aortic flow minus total caval flow or total pulmonary vein flow minus total branch pulmonary artery flow. Median SPC flow/body surface area (BSA) was higher in the pre-Fontan group (1.06 vs 0.43 L/min/m(2), p <0.0001) and decreased nonlinearly with increasing age after the Fontan operation (r(2) = 0.17, p <0.0001). In the Fontan group, patients in the highest quartile of SPC flow had larger ventricular end-diastolic volume/BSA (p <0.0001) and were older at the time of Fontan surgery (p = 0.04), but SPC flow/BSA was not associated with heart failure symptoms, atrial or ventricular arrhythmias, atrioventricular valve regurgitation, the ventricular ejection fraction, or peak oxygen consumption. In multivariate analysis of all patients (n = 116), higher SPC flow was independently associated with pre-Fontan status, unilateral branch pulmonary artery stenosis, a diagnosis of hypoplastic left-heart syndrome, and previous catheter occlusion of SPCs (model r(2) = 0.37, p <0.0001). In conclusion, in this cross-sectional study of single-ventricle patients, BSA-adjusted SPC flow was highest in pre-Fontan patients and decreased after the Fontan operation with minimal clinical correlates aside from ventricular dilation.

Hypoplastic left heart syndrome: current considerations and expectations

In the recent era, no congenital heart defect has undergone a more dramatic change in diagnostic approach, management, and outcomes than hypoplastic left heart syndrome (HLHS). During this time, survival to the age of 5 years (including Fontan) has ranged from 50% to 69%, but current expectations are that 70% of newborns born today with HLHS may reach adulthood. Although the 3-stage treatment approach to HLHS is now well founded, there is significant variation among centers. In this white paper, we present the current state of the art in our understanding and treatment of HLHS during the stages of care: 1) pre-Stage I: fetal and neonatal assessment and management; 2) Stage I: perioperative care, interstage monitoring, and management strategies; 3) Stage II: surgeries; 4) Stage III: Fontan surgery; and 5) long-term follow-up. Issues surrounding the genetics of HLHS, developmental outcomes, and quality of life are addressed in addition to the many other considerations for caring for this group of complex patients.

Hypoplastic left heart syndrome with restrictive atrial septum and advanced heart block documented with a novel fetal electrocardiographic monitor

Hypoplastic left ventricle with congenital heart block has been reported previously in a fetus with concurrent left atrial isomerism and levo-transposition of the great arteries. We present the unusual case of an infant diagnosed in utero with hypoplastic left heart syndrome, a restrictive atrial septum and advanced heart block but with D-looping of the ventricles and no atrial isomerism. In addition, fetal heart rhythm was documented with the assistance of a new fetal electrocardiographic monitor.

Catheter takedown in the management of the acutely failing Fontan circulation

The acutely failing Fontan circulation requires urgent management to decompress the systemic venous pressures and augment cardiac output. This may involve the use of extracorporeal membrane oxygenation support to preserve life. Catheter-based effective Fontan takedown is an alternative to surgery in these patients, who are acutely unstable, and offers the potential for an adjustable fenestration.

Prenatal diagnosis of hypoplastic left heart syndrome in current era

We sought to evaluate the relation of a prenatal diagnosis (preDx) with morbidity and mortality during the initial hospitalization in a contemporary cohort of patients with hypoplastic left heart syndrome (HLHS). A retrospective study of patients with HLHS presenting from 1999 to 2010 was performed. Patients with genetic disorders or a gestational age <34 weeks or who had intentionally received comfort care only were excluded. Of the 81 patients meeting the study criteria, 49 had a preDx and 32 were diagnosed postnatally (postDx). Birth weight (median 3.0 vs 3.4 kg; p = 0.007) and gestational age (median 38 vs 39 weeks; p <0.001) were lower in the preDx than in the postDx patients. Preoperatively, the postDx patients were intubated more frequently (97% vs 71%, p = 0.004) and ventilated longer (median 96 vs 24 hours, p = 0.005) than the preDx patients. They also had more preoperative acidosis, multiorgan failure, tricuspid valve regurgitation, and right ventricular dysfunction. Of the 73 patients undergoing surgery, no difference in survival was seen between the preDx and postDx groups (91% vs 89%). The median duration of postoperative ventilation was 7 days and the median length of stay was 36 days for the 66 survivors, with no difference between the 2 groups. Postoperative morbidities, including chylothorax and infection, were also similar in the preDx and postDx patients. No studied preoperative factor was associated with death, duration of postoperative ventilation, or length of stay. In conclusion, our recent experience has shown that preDx of HLHS was not associated with a survival advantage, fewer postoperative complications, or shorter length of stay. Improved preoperative status was observed in the preDx patients; however, they were born earlier with a lower birthweight. What effect these factors might have on longer term morbidity remains unknown.

Hypoplastic left heart syndrome associated with large omphalocele and hypoplastic left bronchus

We present a patient with the combination of hypoplastic left heart syndrome (HLHS), large omphalocele, and hypoplastic left bronchus who underwent a modified Norwood procedure and was successfully discharged home. The child required tracheostomy with home ventilation and we elected to delay the primary repair of the omphalocele. To our knowledge, this is the first reported case with this combination of anomalies surviving till hospital discharge. Our experience demonstrates the potential viability of patients with concurrent HLHS, large abdominal wall defects, and airway anomalies and may additionally advocate for delayed repair of large omphaloceles in patients with complex congenital heart disease.