Infants with single ventricle heart defects were enrolled in the Single Ventricle Reconstruction (SVR) study to look at how they did after the first stage of surgery (Norwood operation) where babies got one of two kinds of shunts: a modified Blalock-Taussig shunt (MBTS) or right ventricle to pulmonary artery shunt (RV-to-PA shunt).
In this study we wanted to learn if these same children (2-6 years of age) do better with one of the two shunts (RV-to-PA or MBTS) in the years after surgery. Also we wanted to see how other medical and surgical factors affect children’s health and how they develop. Over 500 children were enrolled in this study.
Were enrolled in this follow-up study.
Patients were followed from 14 months until age 6, for a total of 5 years of follow-up.
Developmental outcomes for children in this study varied a great deal.
All children who were enrolled in the first SVR study were invited to enroll in this study.
This study included a medical record review annually until a child reached the age of 6. Cardiac assessments were done with echocardiograms (twice during the study); ECGs and Holter monitors (at age 6); as well as a series of neurodevelopmental and quality of life questionnaires completed annually.
The PHN is grateful to the children and families who participated in this study. See the SVR III study for more information about further follow-up of these families.
J. Newburger, Circulation 2014; 129:2013-2020.
In the Single Ventricle Reconstruction (SVR) trial, 1-year transplant-free survival was better for the Norwood procedure with right ventricle-to-pulmonary artery shunt (RVPAS) compared with a modified Blalock-Taussig shunt (MBTS). At 3 years, we compared transplantation-free survival, echocardiographic right ventricular ejection fraction, and unplanned interventions in the treatment groups. By 3 years, the Norwood procedure with RVPAS compared with MBTS was no longer associated with better transplant-free survival. Moreover, RVPAS subjects had slightly worse right ventricular ejection fraction and underwent more catheter interventions.
C. Goldberg, J Pediatr 2014; 165(3): 490-496.
This study measured neurodevelopment at 3 years of age and compared it to neurodevelopment at 14 months of age in children enrolled in the Single Ventricle Reconstruction trial. Scores on tests to evaluate neurodevelopment were lower at 3 years of age when compared to a normal population. The results suggest that even when 14-month scores are within the normal range, children with single ventricle heart defects may be at risk for developmental impairment at pre-school age and beyond. Therefore, all children with HLHS and related single ventricle malformations should be followed longitudinally to improve recognition of delays and potential for intervention.
P. Burch, J Am Heart Assoc 2014; 3(3):e000079.
Poor growth is associated with poor prognosis in several disease processes. While children with single ventricle heart disease are known to be smaller than their peers at birth, there is limited information regarding growth and development in survivors. In this paper we show that single ventricle survivors continue to grow poorly with regards to both height and weight through the first two surgical palliations and at three years of age.
P. Frommelt, J Am Coll Cardiol 2014; 64(19):2026-35.
The initial shunt type at the Norwood procedure used to supply blood flow to the lungs in infants with single right ventricle anomalies may influence heart muscle function during the second and third years of life. This study tested heart muscle function in children in the SVR trial, comparing those who had a right ventricle-to-pulmonary artery shunt versus the modified Blalock-Taussig shunt. While there were no differences between the groups, a markedly enlarged heart, poor heart muscle function, and significant heart valve enlargement/dysfunction at 14 months of age was associated with poorer survival to the Fontan operation.
C. Ravishankar, J Thorac Cardiovasc Surg. 2016; 151(3):669-675.
In the Single Ventricle Reconstruction trial, infants with hypoplastic left heart syndrome (HLHS) who received a right-ventricle-to-pulmonary-artery shunt (RVPAS) versus a modified Blalock-Taussig shunt (MBTS) had lower early postoperative mortality, but more complications at 14 months. This study explored the effect of shunt type and other patient, medical, and surgical factors on postoperative length of stay (LOS) after the Fontan operation. The type of shunt received at the Norwood surgery did not affect how long a baby stayed in the hospital for the Fontan surgery. Rather, more medical complications before the operation resulted in longer LOS after the Fontan operation.
A. W. Eckhauser, Cardiol Young. 2019 Dec;29(12):1510-1516.
P. Burch, J. Pediatr. 2017; 180:270-274.e6.
There is limited information regarding the long-term growth and development in survivors with single ventricle heart disease. This paper assesses growth in these patients after their final palliative surgery until they are school age. These children continue to grow poorly with regards to both height and weight with height being affected to a greater extent than weight.
W.T. Mahle, J Heart Lung Transplant. 2018 Jul;37(7):879-885.
Heart failure is a known complication following the Norwood procedure for single ventricle anomalies. Examination of the Single Ventricle Reconstruction (SVR) trial cohort revealed that almost 15% of participants developed heart failure following discharge from the Norwood procedure. Shunt type had no association with heart failure. The risk for developing heart failure was highest in the first year of life. Over half of the children who developed heart failure were listed for transplant, though a significant number died while awaiting a transplant. Among transplant-free survivors to 6 years of age, fewer than 5% of children with palliated single ventricle congenital heart disease had class IV symptomatic heart failure. Several procedure and patient-related factors were associated with development of heart failure, including impaired right ventricular function after the Norwood procedure.
K. Mussatto, Cardiol Young. 2018; 28(1):126-133.
Children with hypoplastic left heart syndrome are at a risk for neurodevelopmental delays. This study looked at the types of early intervention services (e.g. speech, occupational, physical therapy) and how frequently services were used from age 1 to 4 years in children who participated in the SVR trial. Significant delay was reported by parents in 18-43% of children at ages 3 and 4. More than half of the children (52-69%) were not receiving services at any age and 20-32% were receiving two or more therapies each year. Despite significant neurodevelopmental delays, early intervention service utilization was low in this group of children.
J.W. Newburger, Circulation. 2018 May; 137(21):2246-2253.
We examined transplant-free survival and other outcomes at 6 years after the Norwood procedure with a right ventricle-to-pulmonary artery shunt (RVPAS) compared to a modified Blalock‒Taussig shunt (MBTS) in children enrolled in the PHN’s Single Ventricle Reconstruction (SVR) trial. The RVPAS group had similar survival without needing a heart transplant at 6 years but required more catheter interventions before the Fontan procedure. After the Fontan procedure, the two shunt groups had similar rates of transplant-free survival and of catheter interventions, as well as similar right heart function, cardiac symptoms, and complications. However, children in both groups had a steady increase in complications over time; by 6 years, 20% had suffered a blood clot, 15% a seizure, and 7.5% a stroke. These data emphasize the importance of close follow-up and the need to find new strategies to improve the long-term outlook for children with single ventricle anomalies.
P. C. Frommelt, Circ Cardiovasc Imaging. 2019 Feb; 12(2): e007865.
T. A. Miller, Pediatrics. 2019 May; 143(5): e20182577.
C. S. Goldberg, Pediatrics. 2019 Nov; 144(5): e20191010.
N. Cain, Journal of the American College of Cardiology 2022; 169:107-112.
This study compared the effect of both shunt type and Fontan type on the incidence of abnormal heart rhythms (arrhythmias) by 6 years of age in the Pediatric Heart Network Single Ventricle Reconstruction Extension Study (SVRII). By 6 years of age, benign ventricular beats were common in the SVR II population, and it was common for participants to be on medication to treat abnormal heart rhythms, but most of those medications also support heart function. Of the 7 patients with death or transplant between 2-6 years, none had ventricular arrhythmias, but compared with transplant-free survivors, they had some differences in ECG measurements (a longer QRS and a trend toward a longer QTc interval). Fast arrhythmias that begin in the top chambers of the heart (atrial tachyarrhythmias) varied by Fontan type, but not by shunt type. We concluded that, despite the potential for increased risk of ventricular arrhythmias and sudden death in the RV to PA shunt group, the data from the SVR and SVRII studies do not show any significant differences by shunt type or increased risk by 6 years of follow-up. The findings support the need for ongoing surveillance for arrhythmias in the SVR population.
K. A. Mussatto, The Journal of Pediatrics 2023; 255:50-57.
Hypoplastic left heart syndrome (HLHS) has a significant impact on both children and families. The purpose of this study was to gain an understanding of how family factors (parent mental health, quality of life, family resources, function and family management of condition) are associated with psychosocial outcomes in children with HLHS at 6 years of age. Parent mental health, quality of life, family resources and family function had no significant relationships to child psychosocial outcomes. Parent perceptions that their child had a normal life despite their heart condition, that the condition was manageable and had a lower impact on family daily life were associated with better child adaptive behavior, adaptive skills and fewer internalizing behavior problems (depression, anxiety, somatic complaints). Improved understanding of the associations between family factors and child outcomes should guide counseling and the development of tailored interventions to capitalize on each family’s strengths.