Heart DefectsSVRIIINCT02455531
Long-term Outcomes of Children With Hypoplastic Left Heart Syndrome and the Impact of Norwood Shunt Type
An observational study of Heart Defects, run by Carelon Research.
Trial summary
The purpose of this study is to compare direct and indirect measures of right ventricular (RV) systolic and diastolic function between 11 year old subjects who had been randomly assigned to receive a right ventricle to pulmonary artery shunt (RVPAS) vs. Read more about this study
- Who is it for?
- Ages 10 to 12 years
- Conditions the study is for
- Heart Defects
- How many people
- 237 participants
- Where
- No sites listed yet
- Study dates
- Jun 2015to Dec 2025
- Phase
- Observational
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 10 to 12 years
- All sexes
- No healthy volunteers
- Child
Study population: All SVR study cohort members will be contacted to assess for vital status. Transplant free survivors will be approached to participate in the in-person assessment.
Who may be able to join
- All SVR study cohort members will be contacted to assess for vital status. Transplant free survivors will be approached to participate in the in-person assessment.
Who cannot join
- Patients who have undergone cardiac transplantation or biventricular conversion from all outcomes other than vital status.
- Those with pacemakers will be excluded from the CMR, and patients <130 cm in height will be excluded from the exercise test.
About this study
Official title: Long-term Outcomes of Children With HLHS (Hypoplastic Left Heart Syndrome) and the Impact of Norwood Shunt Type (A Study Conducted by the Pediatric Heart Network)
The purpose of this study is to compare direct and indirect measures of right ventricular (RV) systolic and diastolic function between 11 year old subjects who had been randomly assigned to receive a right ventricle to pulmonary artery shunt (RVPAS) vs. a modified Blalock-Taussig shunt (MBTS) at the time of the Norwood operation.
Read the detailed description
The Single Ventricle Reconstruction (SVR) trial was the first multicenter, randomized clinical trial to compare two operations in the field of congenital heart disease.8,11 Children with HLHS and other related single RV lesions were enrolled and randomized to receive either a MBTS or a RVPAS at the time of the initial Norwood procedure. This landmark study provided extraordinary insight not only into the consequences of both shunt types, but also into the course, treatment responses and short- and mid-term outcomes for these medically complex patients. Through the SVR Trial and SVR Extension Study (SVR II), outcomes, including but not limited to the primary outcome of transplant-free survival, have now been evaluated in this patient cohort when the last enrolled patient reached 12 months and again at 3 years of age. While early post-operative transplant-free survival during the interstage period7 and at one year8 was better for those children randomized to a RVPAS, survival by the 3-year evaluation appeared equivalent between the two shunt types. Moreover, RVEF was somewhat diminished and the number of interventions was higher in the RVPAS group.12 These findings raised concern that the RV dysfunction in the RVPAS group may be progressive, leading to significantly worse long-term outcomes; if so, the benefits of the RVPAS for short-term survival may be outweighed by longer-term morbidity and mortality. Thus, the optimal surgical approach for newborns with HLHS and related single RV lesions remains unclear.
The Pediatric Heart Network (PHN) Investigators have a unique opportunity and responsibility to analyze the effect of the type of systemic-to-pulmonary artery shunt placed during the Norwood procedure on longer-term survival, as well as to define its effect on other long-term outcomes in this multi-institutional cohort of exquisitely characterized subjects with single RV lesions. As subjects enrolled in the SVR cohort approach a decade of age, the investigators aim: 1) to determine if shunt type at the time of Norwood operation is associated with any long-term differences in cardiac function, survival, or contributors to quality of life; and 2) to characterize long-term outcomes and determine risk factors other than shunt type for adverse long-term outcomes in children with HLHS and other related single ventricle anomalies.
- Conditions
- Heart Defects
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Transplant-free survivors | Transplant-free survivors of the SVR cohort (All SVR survivors are eligible to be followed for vital status.) |
What is being measured
The primary outcome is the main question the study is designed to answer.
RVEF at 10-12 Years on MRI
RV ejection fraction (RVEF) at 10-12 years, as measured by cardiac magnetic resonance (CMR).
Measured: assessed between 10-12 years of age, an average of 53.2 days from consent
Secondary outcomes (6)
Death or Cardiac Transplantation
The incidence of death or cardiac transplantation between those randomized to receive a RVPAS vs. a MBTS at the time of the Norwood operation.
Measured: 11 years ± 1 year to 16 years
The Exercise Tolerance Between Those Randomized to a RVPAS vs. a MBTS.
Exercise capacity: Maximal Oxygen Consumption (VO2max), maximal work rate, and anaerobic threshold
Measured: 11 years ± 1 year to 16 years
Atrial and Ventricular Arrhythmias
The incidence of arrhythmias between those randomized to a RVPAS vs. a MBTS.
Measured: 11 years ± 1 year to 16 years
The Neurodevelopmental Outcomes at 11 Years of Age in Those Randomized to a RVPAS vs. a MBTS
Achievement, as measured by the Wechsler Individual Achievement Tests (WIAT) (Math and Reading); Intelligence, as measured by the Wechsler Intelligence Scale for Children (WISC); Other domains of neurodevelopmental function including assessment of language, executive function, visual spatial skills, motor function, memory, social skills, behavior, health-related quality of life (HRQoL) and adaptive function.
Measured: 11 years ± 1 year
Risk Stratification Models
Develop risk stratification models for 1) cardiac outcomes, 2) transplant-free survival, and 3) neurodevelopmental outcomes.
Measured: 11 years ± 1 year to 16 years
Biospecimens
Collect specimens from subjects and their parents to further develop the biologic specimen repository.
Measured: 11 years ± 1 year to 16 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 May 2015 (estimated)
- Study startJun 2015
- Primary completionOct 2020
- Study completionDec 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Heart DefectsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 237 participants (actual)
Sponsor and investigators
- Lead sponsor
- Carelon Research
- Sponsor type
- University, hospital or other
- Collaborators
- National Heart, Lung, and Blood Institute (NHLBI)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02455531
- Sponsor's protocol ID
- U10HL068270-4b
- Other IDs
- U10HL068270
- Acronym
- SVRIII
- Status last verified
- Mar 2025
- First submitted
- 22 May 2015
- Last updated
- 10 Nov 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
Publications
Miller TA, Sharma B, Gongwer R, Trachtenberg FL, Newburger JW, Goldberg CS, Gustafson KE, Gaynor JW, Votava-Smith JK, Lambert LM, Sananes R, Kral MC, Tsang R, Heinrich KP, Cnota J, Shah A, Ilardi D; Pediatric Heart Network Investigators. Neurodevelopmental Outcomes in Early Adolescence: The Pediatric Heart Network's Single Ventricle Reconstruction Trial. Circulation. 2025 Oct 28;152(17):1246-1261. doi: 10.1161/CIRCULATIONAHA.125.074523. Epub 2025 Jul 17.
PubMed 40671650
Study at a glance
From the registry record, last updated by the sponsor on 10 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Long-term Outcomes of Children With HLHS (Hypoplastic Left Heart Syndrome) and the Impact of Norwood Shunt Type (A Study Conducted by the Pediatric Heart Network)
- ClinicalTrials.gov ID
- NCT02455531
- Acronym / sponsor ID
- SVRIII / U10HL068270-4b
- Conditions
- Heart Defects
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 237 participants (actual)
- Lead sponsor
- Carelon ResearchUniversity, hospital or other
- Collaborators
- National Heart, Lung, and Blood Institute (NHLBI)
- Study start
- Jun 2015
- Primary completion
- Oct 2020 (actual)
- Study completion
- Dec 2025 (estimated)
- First posted
- 28 May 2015 (estimated)
- Results
- Posted 10 Nov 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to compare direct and indirect measures of right ventricular (RV) systolic and diastolic function between 11 year old subjects who had been randomly assigned to receive a right ventricle to pulmonary artery shunt (RVPAS) vs. a modified Blalock-Taussig shunt (MBTS) at the time of the Norwood operation.
Detailed description
The Single Ventricle Reconstruction (SVR) trial was the first multicenter, randomized clinical trial to compare two operations in the field of congenital heart disease.8,11 Children with HLHS and other related single RV lesions were enrolled and randomized to receive either a MBTS or a RVPAS at the time of the initial Norwood procedure. This landmark study provided extraordinary insight not only into the consequences of both shunt types, but also into the course, treatment responses and short- and mid-term outcomes for these medically complex patients. Through the SVR Trial and SVR Extension Study (SVR II), outcomes, including but not limited to the primary outcome of transplant-free survival, have now been evaluated in this patient cohort when the last enrolled patient reached 12 months and again at 3 years of age. While early post-operative transplant-free survival during the interstage period7 and at one year8 was better for those children randomized to a RVPAS, survival by the 3-year evaluation appeared equivalent between the two shunt types. Moreover, RVEF was somewhat diminished and the number of interventions was higher in the RVPAS group.12 These findings raised concern that the RV dysfunction in the RVPAS group may be progressive, leading to significantly worse long-term outcomes; if so, the benefits of the RVPAS for short-term survival may be outweighed by longer-term morbidity and mortality. Thus, the optimal surgical approach for newborns with HLHS and related single RV lesions remains unclear.
The Pediatric Heart Network (PHN) Investigators have a unique opportunity and responsibility to analyze the effect of the type of systemic-to-pulmonary artery shunt placed during the Norwood procedure on longer-term survival, as well as to define its effect on other long-term outcomes in this multi-institutional cohort of exquisitely characterized subjects with single RV lesions. As subjects enrolled in the SVR cohort approach a decade of age, the investigators aim: 1) to determine if shunt type at the time of Norwood operation is associated with any long-term differences in cardiac function, survival, or contributors to quality of life; and 2) to characterize long-term outcomes and determine risk factors other than shunt type for adverse long-term outcomes in children with HLHS and other related single ventricle anomalies.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Transplant-free survivors | – | –Transplant-free survivors of the SVR cohort (All SVR survivors are eligible to be followed for vital status.) |
Who may qualify
- Ages
- 10 to 12 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
- Study population
- All SVR study cohort members will be contacted to assess for vital status. Transplant free survivors will be approached to participate in the in-person assessment.
Key inclusion criteria (1 listed)
- All SVR study cohort members will be contacted to assess for vital status. Transplant free survivors will be approached to participate in the in-person assessment.
Key exclusion criteria (2 listed)
- Patients who have undergone cardiac transplantation or biventricular conversion from all outcomes other than vital status.
- Those with pacemakers will be excluded from the CMR, and patients <130 cm in height will be excluded from the exercise test.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
RVEF at 10-12 Years on MRI
Time frame: assessed between 10-12 years of age, an average of 53.2 days from consent
RV ejection fraction (RVEF) at 10-12 years, as measured by cardiac magnetic resonance (CMR).
6 secondary outcomes
Death or Cardiac Transplantation
Time frame: 11 years ± 1 year to 16 years
The Exercise Tolerance Between Those Randomized to a RVPAS vs. a MBTS.
Time frame: 11 years ± 1 year to 16 years
Atrial and Ventricular Arrhythmias
Time frame: 11 years ± 1 year to 16 years
The Neurodevelopmental Outcomes at 11 Years of Age in Those Randomized to a RVPAS vs. a MBTS
Time frame: 11 years ± 1 year
Risk Stratification Models
Time frame: 11 years ± 1 year to 16 years
Biospecimens
Time frame: 11 years ± 1 year to 16 years
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Nov 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 40671650Miller TA, Sharma B, Gongwer R, Trachtenberg FL, Newburger JW, Goldberg CS, Gustafson KE, Gaynor JW, Votava-Smith JK, Lambert LM, Sananes R, Kral MC, Tsang R, Heinrich KP, Cnota J, Shah A, Ilardi D; Pediatric Heart Network Investigators. Neurodevelopmental Outcomes in Early Adolescence: The Pediatric Heart Network's Single Ventricle Reconstruction Trial. Circulation. 2025 Oct 28;152(17):1246-1261. doi: 10.1161/CIRCULATIONAHA.125.074523. Epub 2025 Jul 17.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Heart Defects, run by Carelon Research.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 10 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 10 Nov 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
RVEF at 10-12 Years on MRI (time frame: assessed between 10-12 years of age, an average of 53.2 days from consent). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02455531, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Nov 2025; AzTrials last refreshed its copy on 8 Nov 2026.