Semilunar Valve Interventions for Congenital Heart Disease: JACC State-of-the-Art Review

Donor supply for partial heart transplantation in the United States

BACKGROUND

Congenital heart disease (CHD) is the most common cause of birth defects worldwide. Valvular defects are a common form of CHDs, and, at this time, treatment options for children with unrepairable valve disease are limited. Issues with anticoagulation, sizing, and lack of growth in valve replacement options can lead to high mortality rates and incidence of reoperations. Partial heart transplantation, or transplantation of fresh valve allografts, has recently been described as a strategy to provide a durable and non-thrombogenic alternative to conventional prostheses and provide growth potential in pediatric patients.

METHODS

The United Network for Organ Sharing (UNOS) database was queried to analyze the number of pediatric donor hearts that were not recovered but had viable valves (n = 3565) between January 2010 and September 2021. Recoverable valves were grouped by donor age: infants (age < 1 year), toddlers (age ≥1 and <3 years), and children (age ≥3 and <18 years). Demographic characteristics of donors were analyzed between age groups.

RESULTS

Infants, toddlers, and children had a total of 344, 465, and 2756 hearts with recoverable valves, respectively, over the study period, representing an average of 29, 39, and 230 hearts with recoverable valves per year.

CONCLUSION

The results of our study identify the minimum donor supply for partial heart transplantation. The actual number is likely higher because it includes hearts not entered in the UNOS database and domino transplants from orthotopic heart transplant recipients. Partial heart transplantation is logistically feasible as there are recoverable valves available for all age groups, fulfilling a clinical need in pediatric patients with unrepairable valve disease.

Pediatric pulmonary valve replacements: Clinical challenges and emerging technologies

Congenital heart diseases (CHDs) frequently impact the right ventricular outflow tract, resulting in a significant incidence of pulmonary valve replacement in the pediatric population. While contemporary pediatric pulmonary valve replacements (PPVRs) allow satisfactory patient survival, their biocompatibility and durability remain suboptimal and repeat operations are commonplace, especially for very young patients. This places enormous physical, financial, and psychological burdens on patients and their parents, highlighting an urgent clinical need for better PPVRs. An important reason for the clinical failure of PPVRs is biofouling, which instigates various adverse biological responses such as thrombosis and infection, promoting research into various antifouling chemistries that may find utility in PPVR materials. Another significant contributor is the inevitability of somatic growth in pediatric patients, causing structural discrepancies between the patient and PPVR, stimulating the development of various growth-accommodating heart valve prototypes. This review offers an interdisciplinary perspective on these challenges by exploring clinical experiences, physiological understandings, and bioengineering technologies that may contribute to device development. It thus aims to provide an insight into the design requirements of next-generation PPVRs to advance clinical outcomes and promote patient quality of life.

Residual Lesion Severity Predicts Midterm Outcomes After Congenital Aortic Valve Repair

BACKGROUND

We sought to validate the technical performance score (TPS) as a predictor of midterm outcomes after congenital aortic valve repair.

METHODS

This was a single-center, retrospective review of consecutive patients who underwent aortic valve repair between January 1, 2011, and December 31, 2019. Predischarge echocardiograms were used to assign a TPS for each index operation as class 1, no aortic valve residua; class 2, minor aortic valve residua; or class 3, major aortic valve residua or predischarge reintervention for major residua. The primary outcome was postdischarge (late) unplanned aortic valve reintervention. Secondary outcomes included late mortality and at least moderate aortic regurgitation or stenosis at the latest follow-up or before the earliest reintervention. Associations between TPS and outcomes were assessed using competing risk, Cox proportional hazards, or logistic regression models, adjusting for preoperative patient- and procedure-related covariates.

RESULTS

Of 507 patients, there were 110 (21.7%) reinterventions, 22 (4.3%) deaths, and 67 (13.2%) cases of at least moderate aortic regurgitation or stenosis at the latest follow-up or earliest reintervention. On multivariable analysis, class 3 patients had a greater risk of reintervention (subdistribution hazard ratio, 2.6; 95% CI, 1.3-5.1; P = .005) and mortality (hazard ratio, 5.3; 95% CI. 1.1-25.2; P = .038) compared with class 1 patients. Adjusting for duration of follow-up, class 3 patients also had a greater risk of at least moderate aortic regurgitation or stenosis at the latest follow-up or earliest reintervention (odds ratio, 7.7; 95% CI, 2.5-24.2; P < .001) vs class 1 patients.

CONCLUSIONS

Patients with major residua after congenital aortic valve repair have significantly worse midterm outcomes compared with those with no residua, warranting closer follow-up.

Transcatheter and Surgical Aortic Valve Implantation in Children, Adolescents, and Young Adults With Congenital Heart Disease

Transcatheter aortic valve implantation (TAVI) is common in adults but rare in children and adolescents. Since 2014, our institution has incorporated a transcatheter approach as an option for aortic valve replacement in this population. The purpose of this study was to compare short-term outcomes of TAVI with surgical aortic valve replacement (SAVR). This single-center, retrospective study included patients aged 10 to 21 years who had a native SAVR or TAVI between January 2010 to April 2020. Comparative analysis of baseline characteristics and a composite outcome (stroke within 6 months, readmission within 30 days, death) between SAVR and TAVI were made using chi-square test or Wilcoxon rank sum test, as appropriate. Of the 77 patients who underwent native aortic valve implantation during the study period (60 SAVR, 17 TAVI), 46 were aged 10 to 21 years (30 SAVR, 16 TAVI). Median follow-up was 3.8 years (interquartile range 1.5 to 4.9) for the SAVR group and 1.5 years (interquartile range 1.1 to 1.2) for the TAVI group. There was no difference in the composite outcome between groups. Patients in the SAVR group were more likely to have undergone concomitant surgical intervention and have longer intensive care unit and hospital stays. In conclusion, our study suggests similar short-term outcomes between SAVR and TAVI in children and young adults aged 10 to 21 years. Longer-term studies are essential to understand the utility of TAVI and to better consider the option of a transcatheter approach as an alternative to SAVR in the pediatric population.

Editor-in-Chief's Top Picks From 2021

Each week, I record audio summaries for every paper in JACC, as well as an issue summary. This process has become a true labor of love due to the time they require, but I am motivated by the sheer number of listeners (16M+), and it has allowed me to familiarize myself with every paper that we publish. Thus, I have selected the top 100 papers (both Original Investigations and Review Articles) from distinct specialties each year. In addition to my personal choices, I have included papers that have been the most accessed or downloaded on our websites, as well as those selected by the JACC Editorial Board members. In order to present the full breadth of this important research in a consumable fashion, we will present these abstracts in this issue of JACC, as well as their Central Illustrations and podcasts. The highlights comprise the following sections: Artificial Intelligence & Machine Learning (NEW section), Basic & Translational Research, Biomarkers (NEW section), Cardiac Failure & Myocarditis, Cardiomyopathies & Genetics, Cardio-Oncology, Cardiovascular Disease in Women, Coronary Disease & Interventions, Congenital Heart Disease, Coronavirus, Hypertension, Imaging, Metabolic & Lipid Disorders, Neurovascular Disease & Dementia, Promoting Health & Prevention, Rhythm Disorders & Thromboembolism, Vascular Medicine, and Valvular Heart Disease.^1-100.