Hill KD, Kang L, Wang Q, Newburger JW, Gaynor JW, Burns KM, Williams R, Trachtenberg F, McCrindle BW, Graham EM, Pizarro C, et al. Single-Ventricle Disease: Long-Term Outcomes and Global Morbidity in the Single Ventricle Reconstruction Trial. J Am Coll Cardiol. 2026;87:3114-3133. doi:10.1016/j.jacc.2026.01.049.
PubMed: https://pubmed.ncbi.nlm.nih.gov/41811273/
Take-Home Points
- Sixteen-year follow-up of the landmark SVR trial demonstrated that death, transplantation, or major morbidity occurred in 87% of participants with single-ventricle heart disease.
- Only 12% of patients survived free from major morbidity through long-term follow-up.
- The investigators developed an innovative hierarchical “global rank” endpoint incorporating survival, transplantation, adaptive functioning, quality of life, ventricular function, lymphatic complications, and hospitalization burden.
- Overall long-term outcomes did not differ significantly between the right ventricle-to-pulmonary artery shunt (RVPAS) and modified Blalock-Taussig-Thomas shunt (MBTTS).
- Prematurity emerged as one of the strongest predictors of adverse long-term outcomes, while significant variability persisted between centers.
- Patients with moderate or severe pre-Norwood tricuspid regurgitation experienced worse outcomes when treated with an RVPAS, a finding that warrants additional investigation.
Commentary from Dr. Varun Aggarwal (Wilmington, DE, USA), editor-in-chief of Congenital Heart Disease Journal Watch:
Few studies have influenced modern congenital heart surgery as profoundly as the Single Ventricle Reconstruction (SVR) Trial. When the original trial was published in 2010, the question appeared straightforward: which Norwood shunt strategy offered the greatest likelihood of survival? The early answer favored the right ventricle-to-pulmonary artery shunt, and the results quickly altered surgical practice across North America. Yet as the years passed, it became increasingly apparent that transplant-free survival alone could not fully describe the life course of children born with single-ventricle heart disease. The current report represents the culmination of more than two decades of follow-up and asks a far more important question: what does long-term life actually look like for survivors?
The answer is both remarkable and sobering.
The remarkable aspect is survival itself. Modern congenital heart surgery has transformed hypoplastic left heart syndrome and related single-right-ventricle lesions from conditions associated with near-universal mortality into chronic diseases compatible with survival into adolescence and adulthood. Entire generations of patients are now reaching milestones that were once unimaginable. Yet survival has exposed a second reality. The overwhelming majority of survivors experience substantial health burdens that extend far beyond the operating room and continue accumulating throughout childhood and adolescence.
The headline finding of this analysis is striking- only 12% of patients remained free of major morbidity during long-term follow-up. Stated differently, nearly nine of every ten children experienced death, transplantation, severe impairment in adaptive functioning, impaired quality of life, ventricular dysfunction, lymphatic complications, or other major adverse outcomes. These data fundamentally challenge traditional interpretations of success in single-ventricle heart disease.
Historically, congenital heart programs have focused on mortality because mortality was the dominant threat. As surgical outcomes improved, however, the limitations of survival-based endpoints became increasingly obvious. A child who survives but develops severe neurodevelopmental impairment, progressive heart failure, poor adaptive functioning, or markedly impaired quality of life experiences a very different trajectory than a child who remains healthy and fully independent. Traditional survival analyses often fail to distinguish between those futures. This study attempts to correct that deficiency by introducing a novel global rank endpoint designed to capture the entire spectrum of disease burden.
The methodological innovation deserves special recognition. Rather than simply counting deaths or transplants, investigators created a hierarchical outcome structure that incorporated adaptive behavior, quality of life, heart transplantation, major lymphatic complications, ventricular dysfunction, and hospitalization burden. Importantly, the framework was developed with input from clinicians, researchers, and families of children with single-ventricle heart disease. The resulting metric more closely reflects the outcomes that matter most to patients and parents. Few families ask only whether their child will survive. They ask whether their child will learn, grow, participate, function independently, and enjoy a meaningful quality of life. The global rank endpoint attempts to measure exactly those outcomes.
Perhaps the most powerful aspect of the manuscript is its visualization of the cumulative burden of disease. Death remained the most common adverse outcome, affecting 39% of the original cohort. However, survival did not equate to freedom from morbidity. Severe impairment in adaptive function, major quality-of-life limitations, ventricular dysfunction, heart failure, protein-losing enteropathy, plastic bronchitis, and transplantation continued to emerge years after the initial surgery. The data reinforce an uncomfortable but important truth: for many patients, the Fontan pathway should not be viewed as a sequence of surgeries but as the beginning of a lifelong chronic disease process.
The extensive neurodevelopmental data generated by the SVR program over the past decade become even more meaningful when viewed through this broader lens. Prior SVR publications demonstrated deficits in intellectual functioning, executive function, adaptive behavior, social functioning, and academic achievement. The current analysis brings these outcomes into the same conversation as mortality and transplantation. This is a significant conceptual advance for the field. Neurodevelopmental health is not a secondary outcome. For many survivors, it is one of the most important determinants of long-term independence and quality of life.
Another important finding involves prematurity. Nearly all premature infants experienced significant morbidity, and outcomes were dramatically worse than those observed among term infants. Mortality approached 62% in premature patients, compared with 36% among term infants, while survival free of major morbidity was exceedingly uncommon. These findings are consistent with earlier analyses from the SVR cohort but become even more compelling within the context of the global rank endpoint. Prematurity continues to exert profound effects that extend well beyond infancy and remain evident more than a decade later.
The study also uncovered substantial variability among participating centers. Mortality ranged from less than 20% at some sites to more than 60% at others. Similarly, long-term survival free of major morbidity varied dramatically across institutions. Volume alone did not explain these differences. Instead, the findings suggest that outcomes are influenced by the entire continuum of care, including perioperative management, outpatient surveillance, rehabilitation services, developmental support, and long-term multidisciplinary follow-up. As congenital heart disease increasingly becomes a lifelong condition, excellence must be defined by more than operative survival alone.
The most provocative finding was the interaction between shunt type and pre-Norwood tricuspid regurgitation. Although overall outcomes did not differ significantly between shunt strategies, patients with moderate or severe tricuspid regurgitation experienced worse long-term outcomes when treated with an RVPAS. Sensitivity analyses demonstrated a substantially increased mortality hazard in this subgroup. The authors appropriately caution that this observation should be viewed as hypothesis-generating because only 12% of participants met these criteria. Nevertheless, the finding raises important questions regarding individualized surgical decision-making and highlights the possibility that not all single-ventricle patients respond similarly to the same intervention.
Perhaps the greatest contribution of this paper is philosophical. The authors argue that future research should focus not only on extending survival but also on preserving neurodevelopment, optimizing quality of life, preventing ventricular dysfunction, reducing heart failure, and mitigating long-term organ injury. This represents a maturation of the entire field. The first era of single-ventricle research focused on survival. The next era must focus on health span.
The SVR cohort remains the most deeply phenotyped longitudinal single-ventricle population ever assembled. As these patients transition into adulthood, the lessons learned from their experiences will increasingly shape the future of congenital heart disease care. The challenge for clinicians is no longer simply helping children survive. The challenge is ensuring that survivors thrive.
Clinical Perspective
The SVR Trial demonstrates that survival alone dramatically underestimates the burden of single-ventricle heart disease. Despite major advances in surgical outcomes, 87% of patients experienced death, transplantation, or substantial morbidity during long-term follow-up. Future progress in congenital heart disease will be measured not only by whether patients survive, but by whether they maintain cognitive function, quality of life, physical independence, and long-term cardiovascular health.
