Mortality after total cavopulmonary connection in children with the down syndrome

Genetic syndromes associated with congenital heart disease

Congenital heart defects are the most common type of birth defect, affecting 1% of live births. The underlying cause of congenital heart disease is frequently unknown. However, advances in human genetics and genome technologies have helped expand congenital heart disease pathogenesis knowledge during the last few decades. When the cardiac defects are part of a genetic syndrome, they are associated with extracardiac conditions and require multidisciplinary care and surveillance. Some genetic syndromes can have subtle clinical findings and remain undiagnosed well into adulthood. Each syndrome is associated with specific congenital and acquired comorbidities and a particular clinical risk profile. A timely diagnosis is essential for risk stratification, surveillance of associated conditions and counselling, particularly during family planning. However, genetic testing and counselling indications can be challenging to identify in clinical practice. This document intends to provide an overview of the most clinically relevant syndromes to consider, focusing on the phenotype and genotype diagnosis, outcome data, clinical guidelines and implications for care.

Cardiovascular Complications of Down Syndrome: Scoping Review and Expert Consensus

Cardiovascular disease is a leading cause of morbidity and mortality in individuals with Down syndrome. Congenital heart disease is the most common cardiovascular condition in this group, present in up to 50% of people with Down syndrome and contributing to poor outcomes. Additional factors contributing to cardiovascular outcomes include pulmonary hypertension; coexistent pulmonary, endocrine, and metabolic diseases; and risk factors for atherosclerotic disease. Moreover, disparities in the cardiovascular care of people with Down syndrome compared with the general population, which vary across different geographies and health care systems, further contribute to cardiovascular mortality; this issue is often overlooked by the wider medical community. This review focuses on the diagnosis, prevalence, and management of cardiovascular disease encountered in people with Down syndrome and summarizes available evidence in 10 key areas relating to Down syndrome and cardiac disease, from prenatal diagnosis to disparities in care in areas of differing resource availability. All specialists and nonspecialist clinicians providing care for people with Down syndrome should be aware of best clinical practice in all aspects of care of this distinct population.

The evolving treatment of congenital heart disease in patient with Down syndrome: Current state of knowledge

OBJECTIVES

Children with Down syndrome are usually seen as not worthy of high-risk cardiac surgery. Through this review, we try to show the results of curative and palliative surgery for functional single ventricle syndrome in patients with Down syndrome, as there is currently no standard protocol for the treatment of this category of patients.

METHODS

An exhaustive search of all related published medical literature included the following domains: Down syndrome and diagnosis, Down syndrome and taxonomy, Down syndrome, and natural history, Down syndrome and cardiovascular abnormalities, Down syndrome and pulmonary hypertension, Down syndrome and institutionalization, Down syndrome and surgical repair, Down syndrome, and single ventricle palliation, Down syndrome and Glenn, Down syndrome, and Fontan.

RESULTS

12 articles were included from 775 identified. Low-risk cardiac surgery procedure should be provided for Down syndrome with a balanced ventricular septal defect. There is no universal agreement about the surgical approach for Down syndrome with unbalanced ventricular septal defects, but it can be performed at relatively low risk.

CONCLUSIONS

TCPC in Down syndrome patients could be a relatively low-risk procedure if patients are prepared well and their pulmonary vascular resistance is low. Randomized prospective studies are required to show the long-term impact of TCPC palliation and develop a better understanding of standardized care of these patients.

National outcomes of the Fontan operation with endocardial cushion defect

BACKGROUND

The traditional outcomes of the Fontan operation (FO) in endocardial cushion defect (ECD) patients have been suboptimal. Previous studies have been limited by the smaller number of ECD patients, longer study period with an era effect, and do not directly compare short-term outcomes of FO in ECD patients with non-ECD patients. Our study aims to address these shortcomings.

METHODS

A retrospective analysis of the Kids Inpatient Database (2009, 2012, and 2016) for the FO was done. The groups were divided into those who underwent FO with ECD as compared to non-ECD diagnosis. The data were abstracted for demographics, clinical characteristics, and operative outcomes. Standard statistical tests were used.

RESULTS

Three thousand three hundred eighty patients underwent the FO of which 360 patients (11%) were FO-ECD. ECD patients were more likely to have Down syndrome, Heterotaxy syndrome, transposition/DORV, and TAPVR as compared to non-ECD patients. FO-ECD had a higher discharge-mortality (2.84% vs. 0.45%, p = .04). The length of stay (16 vs. 13 days, p = .05) and total charges incurred ($283, 280 vs. $234, 106, p = .03) for the admission were higher in the FO-ECD as compared to non-ECD patients. In multivariable analysis, ECD diagnosis, cardiac arrest, acute kidney injury, and postoperative hemorrhage were predictors of mortality.

CONCLUSION

Contemporary outcomes for FO are excellent with very low overall operative mortality. However, the outcomes in ECD patients are inferior with higher operative mortality than in non-ECD patients. The occurrence of postoperation complications and a diagnosis of ECD were predictive of a negative outcome.

Hemodynamic Characteristics After Fontan Procedure in Patients with Down's Syndrome

Patients with Down's syndrome (DS) are generally regarded as not being good candidates for the Fontan procedure. However, detailed hemodynamic changes over time are not fully clarified. A retrospective chart review of all patients with DS who underwent the Fontan procedure and 5 times that number of Fontan patients without DS performed in Fukuoka Children's Hospital and Kyushu University Hospital. Seven Fontan patients with DS were identified, and 35 Fontan patients without DS were recruited. During the mean observational periods of 14.7 years and 15.0 years (DS and non-DS, respectively) after the Fontan procedure, only one DS patient died. Central venous pressure (CVP) and transpulmonary pressure gradient significantly increased, and arterial oxygen saturation significantly decreased over time in DS patients after the Fontan procedure compared with those without DS. CVP in DS patients after the Fontan procedure increased over time compared with non-DS patients. Better management including the efficacy of Pulmonary arterial hypertension-specific therapy should be clarified in further studies.

Single Ventricle-A Comprehensive Review

In this paper, the author enumerates cardiac defects with a functionally single ventricle, summarizes single ventricle physiology, presents a summary of management strategies to address the single ventricle defects, goes over the steps of staged total cavo-pulmonary connection, cites the prevalence of inter-stage mortality, names the causes of inter-stage mortality, discusses strategies to address the inter-stage mortality, reviews post-Fontan issues, and introduces alternative approaches to Fontan circulation.

Pulmonary hypertension in children with Down syndrome

Individuals with Down syndrome (DS) have an increased risk of developing pulmonary hypertension (PH). In this review, we explore the epidemiology and clinical characteristics of PH in the population with DS and examine genetic, molecular and clinical contributions to the condition. The presence of an additional copy of chromosome 21 (trisomy 21) increases the risk of developing PH in children with DS through many mechanisms, including increased hemodynamic stress in those with congenital heart disease, hypoxemia through impaired ventilation to perfusion matching secondary to developmental lung abnormalities, pulmonary hypoplasia from pulmonary vascular endothelial dysfunction, and an increase in pulmonary vascular resistance often related to pulmonary comorbidities. We review recent studies looking at novel biomarkers that may help diagnose, predict or monitor PH in the population with DS and examine current cardiopulmonary guidelines for monitoring children with DS. Finally, we review therapeutic interventions specific to PH in individuals with DS. Contemporary work has identified exciting mechanistic pathways including the upregulation of antiangiogenic factors and interferon activity, which may lead to additional biomarkers or therapeutic opportunities. Throughout the manuscript, we identify gaps in our knowledge of the condition as it relates to the population with DS and offer suggestions for future clinical, translational, and basic science research.

Trisomy 21 Patients Undergoing Cavopulmonary Connections Need Improved Preoperative and Postoperative Care

BACKGROUND

Patients with trisomy 21 (T21) often have elevated pulmonary vascular resistance, which may result in a suboptimal cavopulmonary connection (CPC) after a Glenn or Fontan operation. The purpose of this study was to assess, in a nationwide, multiinstitution cohort of patients with CPC, the impact of T21 on patient morbidity, mortality, and resource use.

METHODS

A total of 23,271 pediatric patients with CPC (2004 to 2019) at 50 US hospitals were evaluated using the Pediatric Health Information System database. Univariable and multivariable regression analyses were used to assess risk-adjusted associations between Down syndrome and other risk factors and postoperative measures of morbidity, mortality, lengths of stay, and cost of hospitalization.

RESULTS

The overall prevalence of T21 among patients who had undergone Glenn and Fontan procedures was 1.5% (199 of 13,268) and 0.8% (78 of 1003), respectively. Among both CPC cohorts, T21 status significantly increased unadjusted mortality, hospital lengths of stay, and total costs of hospitalization compared with the non-T21 CPC cohort (all P < .001). Patients with T21 also had a higher incidence of prolonged mechanical ventilation compared with patients without T21 in both Glenn and Fontan groups (P < .001). Multivariable regression analysis further estimated that patients with T21 are associated with a 5.5-fold increase in mortality (P < .001) compared with patients without T21. Finally, patients with T21 had increased long-term mortality compared with their peers.

CONCLUSIONS

T21 significantly increases risk-adjusted morbidity, inpatient mortality, long-term mortality, and resource use after cavopulmonary connections. Further investigation is needed to clarify modifiable patient-level and center-specific risk factors to improve outcomes for patients with T21.

Differences in morbidity and mortality in Down syndrome are related to the type of congenital heart defect

Morbidity and mortality in Down syndrome (DS) are mainly related to congenital heart defects (CHDs). While CHDs with high prevalence in DS (typical CHDs), such as endocardial cushion defects, have been extensively described, little is known about the impact of less common CHDs (atypical CHDs), such as aortic coarctation and univentricular hearts. In our single-center study, we analyzed, in observational, retrospective manner, data regarding cardiac features, surgical management, and outcomes of a cohort of DS patients. Literature review was performed to investigate previously reported studies on atypical CHDs in DS. Patients with CHDs were subclassified as having typical or atypical CHDs. Statistical analysis was performed for comparison between the groups. The study population encompassed 859 DS patients, 72.2% with CHDs, of which 4.7% were atypical. Statistical analysis showed a significant excess in multiple surgeries, all-cause mortality and cardiac mortality in patients with atypical CHDs (p = .0067, p = .0038, p = .0001, respectively). According to the Kaplan-Meier method, survival at 10 and 40 years was significantly higher in typical CHDs (99 and 98% vs. 91 and 84%, log rank <0.05). Among atypical CHDs, it seems that particularly multiple complex defects in univentricular physiology associate with a worse outcome. This may be due to the surgical difficulty in managing univentricular hearts with multiple defects concurring to the clinical picture or to the severity of associated defects themselves. Further studies need to address this specific issue, also considering the higher pulmonary pressures, infective complications, and potential comorbidities in DS patients.

Significant Improvements in Mortality After the Fontan Operation in Children With Down Syndrome

BACKGROUND

Down syndrome (DS) is considered a risk factor for mortality associated with the Fontan operation. The objective was to show the contemporary short-term outcome of the Fontan operation for a functionally univentricular heart in patients with DS and non-DS, along with an analysis of significant predictors for in-hospital mortality.

METHODS

This was a retrospective study using The Society of Thoracic Surgeons Congenital Database to assess in-hospital mortality and its predictors in patients with DS and non-DS undergoing the Fontan operation over 16 years (2001-2016). The primary outcome was in-hospital mortality. Statistical analysis was performed using univariable and multivariable logistic regression models.

RESULTS

Our study cohort consisted of 12,074 patients (81 DS and 11,993 non-DS). The overall in-hospital mortality rate significantly improved in the recent era (2009-2016): 2.4% to 1.3%, P < .001. The DS group had a higher in-hospital mortality rate (12.3% vs 1.6%, P < .001) with an odds ratio of 8.6 (95% confidence interval, 4.4-17.0). The DS group had a higher 30-day mortality rate, a longer median postoperative length of stay, and a higher incidence of postoperative complications. The multivariable model showed that DS was the strongest predictor of in-hospital mortality, with an odds ratio of 11.6 (95% confidence interval, 5.1-26.4), adjusted for other significant variables including era effect, weight, and primary cardiac diagnosis.

CONCLUSIONS

The in-hospital mortality for the Fontan operation significantly improved in the contemporary era. DS was a significant risk factor for in-hospital morbidity and mortality associated with the Fontan operation.

Surgical palliation of univentricular heart disease in children with Down's syndrome: A systematic review

Objectives

No standard protocol is available for the management of children with Down's syndrome (DS) and a functional single ventricle. This review attempts to determine the outcomes of the single ventricular surgical palliation pathway in high-risk children with DS.

Methods

Several databases were searched using the following MeSH terms: ‘Congenital heart disease’, ‘Atrioventricular septal defect’, ‘Balanced AVSD’, ‘Unbalanced AVSD’, ‘Down's syndrome’, ‘Univentricular repair’, ‘bidirectional Glenn procedure’, and ‘Fontan procedure’. A structured algorithm was used for the selection of studies for an in-depth analysis.

Results

There was no universal agreement on the best surgical approach for unbalanced atrioventricular septal defect in DS. The majority of paediatric cardiac surgeons did not recommend the complete Fontan procedure; conversely, the use of a Glenn shunt (superior cavopulmonary connection) was preferred.

Conclusions

Careful assessment of the suitability for Fontan surgery, including the absence of elevated pulmonary vascular resistance, pulmonary arterial anatomy, and function of the dominant ventricle, is mandatory. A staged surgical procedure ending with complete Fontan repair provides acceptable medium-term results.

Postoperative and long-term outcomes in children with Trisomy 21 and single ventricle palliation

OBJECTIVE

Patients with Trisomy 21 (T21) and single ventricle (SV) physiology present unique challenges compared to euploidic counterparts. This study reports postoperative and long-term outcomes in patients with T21 and SV palliation.

DESIGN

This retrospective cohort study from the Pediatric Cardiac Care Consortium (PCCC) included patients with T21 (<21 years old) that underwent surgical palliation for SV between 1982 and 2008 and control patients without known genetic anomaly following Fontan palliation for similar diagnoses. Kaplan-Meier survival plots were created based on death events obtained from the PCCC and by linkage with the National Death Index (NDI) and the Organ Procurement and Transplantation Network (OPTN) through 2014 for patients with adequate identifiers.

RESULTS

We identified 118 children with T21 who underwent initial surgical SV palliation. Among 90 (75.6%) patients surviving their first surgery, 66 (73.3%) underwent Glenn anastomosis and 25 (27.8%) completed Fontan palliation with in-hospital survival of 80.3% and 76.0%, respectively. Fifty-three patients had sufficient identifiers for PCCC-NDI-OPTN linkage. Ten-year survival, conditioned on discharge alive after the Fontan procedure, was 66.7% compared to 92.2% for 51 controls without genetic anomaly (P = .001). Median age at death for T21 patients following initial surgical SV palliation was 2.69 years (IQR 1.34-7.12) with most deaths (89.2%) attributed to the underlying congenital heart disease (CHD).

CONCLUSIONS

Children with T21 and SV are at high risk for procedural and long-term mortality related to their genetic condition and underlying CHD. Nevertheless, a select group of patients can successfully complete Glenn or Fontan palliation, reaching satisfactory long-term survival.

Comparison of postoperative chylothorax in infants and children with trisomy 21 and without dysmorphic syndrome: Is there a difference in clinical outcome?

INTRODUCTION

Children with trisomy 21 are prone to postoperative chylothorax, caused by malformation of the lymphatic system, after cardiac surgery. The clinical course of patients diagnosed with postoperative chylothorax and trisomy 21 was compared to that of patients without dysmorphic syndromes. Additionally, differences between the groups in composition, amount, and duration of chyle were analyzed to better understand chylothorax in patients with trisomy 21.

MATERIALS AND METHODS

Retrospective cohort study using inpatient clinical databases during a 10-year period.

RESULTS

A total of 2255 patients underwent cardiac operations during the period, of whom 160 (7.1%) patients were diagnosed with trisomy 21. Chylothorax developed in 122 children; 89 patients were included in our study. Of 160 trisomy 21 patients, 27 (16.9%) developed postoperative chylothorax compared to 62 (3%) of 2095 patients without dysmorphic syndromes (p = <0.001). Time on ventilation, stay in intensive care, hospital stay, mortality, and composition of chylous effusion did not differ between groups. The rate of thrombosis was significantly lower (p = 0.02) in the trisomy 21 group.

CONCLUSION

Children with trisomy 21 and congenital heart disease are more prone to developing chylothorax after heart surgery than those without dysmorphic syndromes. However if they develop this postoperative complication, mortality, chylous composition, time in ICU, and duration of hospital stay is not different to from that of other infants or children with this complication. This is important information for the medical specialists involved and is helpful in counseling parents of children with trisomy 21 undergoing heart surgery.

LEVEL OF EVIDENCE

This is a treatment study evidence level III.

Recent advances in managing septal defects: ventricular septal defects and atrioventricular septal defects

This review discusses the management of ventricular septal defects (VSDs) and atrioventricular septal defects (AVSDs). There are several types of VSDs: perimembranous, supracristal, atrioventricular septal, and muscular. The indications for closure are moderate to large VSDs with enlarged left atrium and left ventricle or elevated pulmonary artery pressure (or both) and a pulmonary-to-systemic flow ratio greater than 2:1. Surgical closure is recommended for large perimembranous VSDs, supracristal VSDs, and VSDs with aortic valve prolapse. Large muscular VSDs may be closed by percutaneous techniques. A large number of devices have been used in the past for VSD occlusion, but currently Amplatzer Muscular VSD Occluder is the only device approved by the US Food and Drug Administration for clinical use. A hybrid approach may be used for large muscular VSDs in small babies. Timely intervention to prevent pulmonary vascular obstructive disease (PVOD) is germane in the management of these babies. There are several types of AVSDs: partial, transitional, intermediate, and complete. Complete AVSDs are also classified as balanced and unbalanced. All intermediate and complete balanced AVSDs require surgical correction, and early repair is needed to prevent the onset of PVOD. Surgical correction with closure of atrial septal defect and VSD, along with repair and reconstruction of atrioventricular valves, is recommended. Palliative pulmonary artery banding may be considered in babies weighing less than 5 kg and those with significant co-morbidities. The management of unbalanced AVSDs is more complex, and staged single-ventricle palliation is the common management strategy. However, recent data suggest that achieving two-ventricle repair may be a better option in patients with suitable anatomy, particularly in patients in whom outcomes of single-ventricle palliation are less than optimal. The majority of treatment modes in the management of VSDs and AVSDs are safe and effective and prevent the development of PVOD and cardiac dysfunction.

Attrition in patients with single ventricle and trisomy 21: outcomes after a total cavopulmonary connection

OBJECTIVES

Data are limited regarding the management of children with trisomy 21 (T21) syndrome and a functional single ventricle (FSV). We evaluated patients with T21 and a FSV who had a total cavopulmonary connection (TCPC).

METHODS

From September 1999 to August 2012, 139 patients with a FSV underwent a TCPC. Sixty-five had unbalanced atrioventricular septal defect. Thirteen had T21. Three (of 13) had heterotaxy syndrome. The mean age at the Fontan operation was 27.6 ± 12.1 months.

RESULTS

The initial procedure was pulmonary artery banding in 9 patients, systemic-to-pulmonary shunt in 2 and Damus-Kaye-Stansel/Norwood procedure in 2. Median follow-up was 69 months (interquartile range 25-75, 21-99). There was 1 death after a Damus-Kaye-Stansel/Norwood procedure and one interstage death after a bidirectional Glenn procedure. Nine (of 11) survivors underwent a Fontan operation. A fenestrated Fontan procedure was the predominate operation in 78%. One patient was deemed unsuitable for a Fontan operation. There was 1 takedown and 1 late death after the Fontan operation. Heterotaxy syndrome did not affect outcome ( P  > 0.05). There was no statistical difference in the pre-Fontan McGoon ratio, hospital length of stay, duration of pleural drainage and Fontan-related adverse events between patients with a dominant right ventricle and those with a left ( P  > 0.05).

CONCLUSIONS

A TCPC in patients with T21 and an FSV is associated with reproducible, satisfactory outcomes. An assisted-Glenn procedure with pulsatile pulmonary blood flow and a fenestrated Fontan may be associated with attenuated perioperative morbidity and late attrition.

Complex Chronic Conditions Among Children Undergoing Cardiac Surgery

Children with complex chronic conditions (CCCs) require a disproportionate amount of inpatient resources and are at increased risk of mortality during hospital admissions. This study examines the impact of non-cardiac, comorbid complex chronic conditions on outcomes in children undergoing congenital heart surgery. All admissions associated with a congenital cardiac surgical procedure in the Kids' Inpatient Database from 1997 to 2012 were examined. Children were classified by the number as well as type (genetic vs. non-genetic) of CCC. Baseline demographics as well as proportion of total inpatient days and total hospitalization charges was assessed. Multivariate regression models examining occurrence of a complication, mortality, prolonged length of stay and high hospitalization charges were constructed. In multivariate models, an increasing number of CCC was associated with increased risk of mortality and complications (mortality: 1 CCC: odds ratio (OR) = 1.17, 95 % CI = 1.03-1.33); ≥2 CCC: OR = 1.54, 95 % CI = 1.26-1.87). Additionally, the presence of a genetic CCC was protective against mortality (OR = 0.71, 95 % CI = 0.56-0.89) while non-genetic CCCs were associated with mortality (OR = 1.62, 95 % CI = 1.41-1.88) and high resource utilization. Over time, the proportion of genetic CCC remained stable while non-genetic CCC increased in prevalence. Complex chronic conditions have a varying association with mortality, morbidity and resource utilization in children undergoing congenital heart surgery. While genetic CCCs were not associated with poor outcomes, non-genetic CCCs were risk factors for morbidity and mortality. These findings suggest that pre-surgical counseling and surgical planning should account for the type of non-cardiac comorbid conditions.

CHD associated with syndromic diagnoses: peri-operative risk factors and early outcomes

CHD is frequently associated with a genetic syndrome. These syndromes often present specific cardiovascular and non-cardiovascular co-morbidities that confer significant peri-operative risks affecting multiple organ systems. Although surgical outcomes have improved over time, these co-morbidities continue to contribute substantially to poor peri-operative mortality and morbidity outcomes. Peri-operative morbidity may have long-standing ramifications on neurodevelopment and overall health. Recognising the cardiovascular and non-cardiovascular risks associated with specific syndromic diagnoses will facilitate expectant management, early detection of clinical problems, and improved outcomes--for example, the development of syndrome-based protocols for peri-operative evaluation and prophylactic actions may improve outcomes for the more frequently encountered syndromes such as 22q11 deletion syndrome.

Case studies of patients successfully and unsuccessfully managed pre- and post-Fontan procedure

As a result of advances and modifications in surgical procedures and the development of drugs for pulmonary arterial hypertension, many patients who have undergone Fontan procedures are able to enjoy good quality of life, without pulmonary arterial hypertension and severe complications. In Shizuoka Children's Hospital, drugs for pulmonary arterial hypertension have long been given to Fontan candidates and patients with established Fontan circulation to maintain sufficient pulmonary blood flow and suppress pulmonary arterial hypertension. We present three typical cases that were treated with anti-pulmonary hypertensive drugs before or after Fontan procedure. The first case had asplenia syndrome, and a single ventricle with major aortopulmonary collateral arteries. Anti-pulmonary hypertensive therapy permitted a Fontan procedure and maintained a good long-term quality of life. The second case was a Down syndrome patient who had progressive cyanosis after a Fontan operation. Anti-pulmonary hypertensive therapy improved cyanosis. The third case suffered from protein-losing enteropathy, for which all procedures and medical therapies were ineffective. Fontan candidates and patients with Fontan circulation have varied anatomical backgrounds and pulmonary properties. We must identify the conditions that lead to successful Fontan procedure and Fontan circulation correction, as well as conditions that result in failed Fontan procedure and poorly-controlled Fontan circulation.

High-risk single ventricle palliation in children with Down syndrome: single institution experience

BACKGROUND

Of the children with Down syndrome 40-50% have cardiac defects and the majority of these cardiac defects are amenable to biventricular repair. The outcome of single ventricle palliation is improving; nonetheless, there are limited data on Down syndrome patients with associated high-risk factors undergoing single ventricle palliation. Our aim was to study the outcomes of children with Down syndrome and high-risk factors on the single ventricle palliation pathway.

METHODS

A retrospective study on all patients with Down syndrome on the single ventricle palliation pathway from 2005 until 2011 was conducted. Operative, clinical, echocardiographic, haemodynamic data, and follow-up data were reviewed.

RESULTS

A total of 310 patients underwent at least one single ventricle surgical intervention. Of those, eight patients had Down syndrome, five of which had associated risk factors - low birth weight, high pulmonary vascular resistance, pulmonary vein stenosis, significant atrioventricular valve regurgitation, and extracardiac anomalies. Mortality in the high-risk group was 80% (4/5), compared with 33% (1/3) in the non-high-risk patients. Overall, after a median follow-up period of 138 days (8-576 days), only 37.5% (3/8) of patients were alive.

CONCLUSION

Despite many improvements in the care of single ventricle patients, the fate of those with Down syndrome and associated high-risk factors remains poor. Further multicentre longer-term studies are needed to validate and quantify the cumulative effects of negative prognostic factors in this complex group of patients.

Unbalanced atrioventricular septal defect: defining the limits of biventricular repair

Unbalanced atrioventricular septal defect (uAVSD) is a challenging lesion with suboptimal outcomes in the current era. Severe forms of uAVSD mandate univentricular repair with well-documented outcomes. Determining the feasibility of biventricular repair (BVR) in patients with moderate forms of uAVSD is difficult. Ventricular hypoplasia has traditionally formed the cornerstone of defining uAVSD. However, malalignment of the atrioventricular junction and related derangements of the anatomy and physiology of the atrioventricular inflow play a central role in establishing and sustaining a biventricular end state. Atrioventricular valve index, left ventricular inflow index, and right ventricle/left ventricle inflow angle are important recently described measures of inflow physiology. Additional patient anatomic and physiologic factors that impact BVR feasibility undoubtedly exist. A recently launched Congenital Heart Surgeons Society prospective inception cohort study will address these and other issues that impair our ability to predict BVR feasibility in uAVSD.