The Pediatric Heart Network's Study on Long-term Outcomes of Children with HLHS and the Impact of Norwood Shunt Type in the Single Ventricle Reconstruction Trial Cohort (SVRIII): Design and Adaptations

Caren S. Goldberg, Department of Pediatrics, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI. Electronic address: cgoldber@med.umich.edu.
J William Gaynor, Division of Cardiothoracic Surgery, Department of Surgery, Children's Hospital of Philadelphia, and the Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
William T. Mahle, Department of Pediatrics, Children's Healthcare of Atlanta, Atlanta, GE.
Chitra Ravishankar, Department of Pediatrics, Children's Hospital of Philadelphia and the Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
Peter Frommelt, Department of Pediatrics, Children's Hospital of Wisconsin, Milwaukee WI.
Dawn Ilardi, Department of Neuropsychology, Children's Healthcare of Atlanta, Emory University, Atlanta GE.
David Bellinger, Department of Neurology, Boston Children's Hospital, Boston, MA.
Stephen Paridon, Department of Pediatrics, Children's Hospital of Philadelphia and the Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
Michael Taylor, Department of Pediatrics, Cincinnati Children's Hospital and Medical Center, Cincinnati OH.
Kevin D. Hill, Department of Pediatrics, Duke University, Durham, NC.
L LuAnn Minich, Department of Pediatrics, The University of Utah and Primary Children's Hospital, Salt Lake City, Utah.

Abstract

BACKGROUND: The Single Ventricle Reconstruction (SVR) Trial was the first randomized clinical trial of a surgical approach for treatment of congenital heart disease. Infants with hypoplastic left heart syndrome (HLHS) and other single right ventricle (RV) anomalies were randomized to a modified Blalock Taussig Thomas shunt (mBTTS) or a right-ventricular-to-pulmonary-artery shunt (RVPAS) at the time of the Norwood procedure. The aim of the Long-term Outcomes of Children with HLHS and the Impact of Norwood Shunt Type (SVR III) study is to compare early adolescent outcomes including measures of cardiac function, transplant-free survival, and neurodevelopment, between those who received a mBTTS and those who received an RVPAS. METHODS: Transplant-free survivors of the SVR cohort were enrolled at 10-15 years of age for multifaceted in-person evaluation of cardiac function (cardiac magnetic resonance [CMR], echocardiogram and exercise test) and neurodevelopmental evaluation. Right ventricular ejection fraction measured by CMR served as the primary outcome. Development of arrhythmias, protein losing enteropathy, and other comorbidities were assessed through annual medical history interview. Through the course of SVR III, protocol modifications to engage SVR trial participants were designed to enhance recruitment and retention. CONCLUSIONS: Evaluation of long-term outcomes will provide important data to inform decisions about the shunt type placed at the Norwood operation and will improve the understanding of cardiovascular and neurodevelopmental outcomes for early adolescents with HLHS.