Long-term outcomes of heart transplantation in adults with congenital heart disease: The impact of single-ventricle versus biventricular physiology.

Objective: Congenital heart disease is a risk factor for mortality after orthotopic heart transplantation; however, the impact of preoperative circulation type and primary congenital heart disease diagnosis remains poorly delineated. Methods: We retrospectively reviewed patients with adult congenital heart disease aged 16 years or more who underwent orthotopic heart transplantation at our institution between 2008 and 2022. Patients were categorized as having single-ventricle or biventricular circulation. The primary end point was 5-year post-transplant survival. Results: Sixty-one patients with adult congenital heart disease (single-ventricle: n = 26 [42.6%], biventricular: n = 35 [57.4%]) underwent orthotopic heart transplantation at 33.7 [interquartile range, 19.1-48.7] years. The most common congenital heart disease diagnosis was hypoplastic left heart syndrome (n = 11, 42.3%) in the single-ventricle group and congenitally corrected transposition of the great arteries (n = 7, 20.0%) in the biventricular group. Twenty-four patients previously underwent Fontan palliation. At transplant, patients in the single-ventricle group were younger (18.5 [interquartile range, 17.6-32.3] years vs 45.0 [interquartile range, 33.0-52.2] years, P < .001) and more likely to have biopsy-proven cirrhosis (46.2% vs 14.3%, P = .01) and protein-losing enteropathy (42.3% vs 2.9%, P < .001). Patients in the single-ventricle group also had longer bypass times (223.4 ± 65.3 minutes vs 187.4 ± 59.5 minutes, P = .03) and longer durations of mechanical ventilatory support (3.5 [interquartile range, 2.0-6.0] days vs 1.0 [interquartile range, 1.0-2.0] days, P < .001). Operative mortality was comparable (11.5% vs 8.6%, P = 1). Median follow-up was 6.0 [interquartile range, 2.4-10.0] years. Five-year survival was worse in the single-ventricle group (66.0% ± 10.0% vs 91.3% ± 4.8%, P = .03), as was freedom from major rejection (58.3% ± 10.2% vs 84.0% ± 6.6%, P = .02). In univariable analysis, hypoplastic left heart syndrome and Fontan circulation were risk factors for post-transplant mortality (hypoplastic left heart syndrome: hazard ratio, 5.0, P < .001; Fontan: hazard ratio, 3.5, P = .03). Conclusions: Adult patients with congenital heart disease undergoing heart transplant with single-ventricle physiology experienced a more complicated post-transplant course, with worse long-term survival and freedom from rejection. Multicenter studies are required to guide orthotopic heart transplantation decision-making in this complex cohort.

Rare coronary artery variants are associated with increased mortality and reinterventions following the arterial switch operation.

OBJECTIVE: To determine the influence of coronary anatomy on long-term outcomes of the arterial switch operation (ASO). METHODS: We retrospectively reviewed patients with transposition of the great arteries or Taussig-Bing anomaly who underwent ASO at our institution between 1992 and 2022. The primary endpoint was freedom from a composite of death, transplantation, and coronary reintervention. RESULTS: A total of 632 patients (median age, 5.0 days; interquartile range [IQR], 4.0-7.0 days) underwent ASO. Coronary anatomy included the following categories: usual (n = 411; 65%), circumflex (Cx) from sinus 2 (n = 89; 14%), inverted (n = 55; 9%), single sinus (n = 46; 7%), and intramural (n = 31; 5%). Overall operative mortality was 3% (n = 16) and highest in patients with intramural cardiac anatomy (n = 3; 10%), although it dropped to 0% in this group in the most recent decade. The median duration of follow-up was 14.5 years (IQR, 6.0-20.3 years). Twenty-year freedom from the primary endpoint was 95 ± 1% for usual anatomy, 99 ± 1% for Cx from sinus 2, 90 ± 4% for inverted, 91 ± 4% for single sinus, and 80 ± 9% for intramural (P < .001). Intramurals had the highest 20-year incidence of coronary reintervention (11 ± 8%). Cox modeling identified intraoperative coronary revision (hazard ratio [HR], 20.1; 95% confidence interval [CI], 9.4-53.9; P < .001), Taussig-Bing anomaly (HR, 4.9; 95% CI, 2.2-10.9; P < .001), and an intramural coronary artery (HR, 2.9; 95% CI, 1.0-8.2; P = .04) to be risk factors for the composite endpoint. CONCLUSIONS: Rare coronary artery variants-particularly intramural-are associated with increased mortality and coronary reinterventions after ASO. A low threshold for unroofing intramurals is likely associated with declining mortality and improved outcomes. Additional investigations are needed to determine the long-term fate of the coronary arteries after ASO.

Ventricular Septation of the Double-Inlet Ventricle: Over Three Decades of Follow-Up.

There is renewed interest in septation of the double-inlet ventricle as an alternative to Fontan palliation. We examined our septation experience with over 30 years of follow-up. We retrospectively reviewed patients with double-inlet ventricle from 1990 to 2011. Patients with two adequate atrioventricular valves, a volume-overloaded ventricle, and no significant subaortic obstruction were septation candidates. Of 98 double-inlet ventricle patients, 9 (9.2%) underwent attempted septation via a one-stage (n = 2, 22.2%) or two-stage (n = 7, 77.8%) approach. Ages at primary septation were 7.5 and 20.2 months. In the staged group, median age at the first and second stage was 8.3 months [range 4.1-14.7] and 22.4 months [range 11.4-195.7], respectively. There were no operative mortalities. Median follow-up was 18.8 years [range 0.4-32.9] and 30-year transplant-free survival was 77.8% ± 13.9%. Both single stage patients are alive and in sinus rhythm; 1 underwent bilateral outflow tract obstruction repair 27 years later. Of 7 patients planned for two-stage septation, there was 1 interval mortality and 1 deferred the second stage. Five patients underwent the second stage; 1 required early reintervention for a residual neo-septal defect and 1 underwent right atrioventricular valve replacement 28 years later. Three patients required a pacemaker preoperatively (n = 1) or after partial septation (n = 2). At latest follow-up, 7 patients have normal biventricular function and no significant valvulopathy. All remain NYHA functional class I. Select double-inlet ventricles may be septated with excellent long-term outcomes. Reconsideration of this strategy is warranted to avoid the sequelae of Fontan circulation.

Staged Ventricular Septation of the Double-Inlet Ventricle: How-I-Do-It.

Ventricular septation of the double-inlet ventricle is a largely abandoned operation due to poor historical outcomes. However, there has been renewed interest in septation as an alternative to Fontan palliation given its long-term sequelae. As one of the few centers to revisit septation in the early 1990s, our institution has long-term data on a series of patients with a double-inlet ventricle who underwent biventricular repair. This manuscript is a summary of our approach to staged septation of the double-inlet ventricle, with a focus on patient selection criteria, surgical techniques, perioperative considerations on timing of interventions, and long-term results. We believe that septation of the double-inlet ventricle should be reconsidered in patients with suitable anatomy in light of the known complications of Fontan palliation.

Long-term autograft dilation and durability after the Ross procedure are similar in infants, children, and adolescents with primary aortic stenosis.

BACKGROUND: Autograft durability and remodeling are thought to be superior in younger pediatric patients after the Ross operation. We sought to delineate the fate of autografts across the pediatric age spectrum in patients with primary aortic stenosis (AS). METHODS: We retrospectively reviewed patients age ≤18 years with primary AS who underwent the Ross operation between 1993 and 2020. Patients were categorized by age. The primary endpoint was autograft dimensional change, and secondary endpoints were severe neo-aortic insufficiency (AI) and autograft reintervention. RESULTS: A total of 119 patients underwent the Ross operation, including 37 (31.1%) in group I (age <18 months), 24 (20.2%) in group II (age 18 months-8 years), and 58 (48.7%) in group III (age 8-18 years). All groups exhibited similar annular growth rates within the first 5 postoperative years, followed by a collective decrease in annulus growth rates from year 5 to year 10. Group III experienced rapid sinus dilation in the first 5 years, followed by stabilization of the sinus z-score from year 5 to year 10, whereas groups I and II demonstrated stable sinus z-scores over 10 years. There were 4 early deaths (3.4%) and 2 late deaths (1.7%) at a median follow-up of 8.1 years (range, 0.01-26.3 years). At 15 years, the incidences of severe neo-AI (0.0 ± 0.0% vs 0.0 ± 0.0% vs 3.9 ± 3.9%; P = .52) and autograft reintervention (8.4 ± 6.0% vs 0.0 ± 0.0% vs 2.4 ± 2.4%; P = .47) were similar in the 3 groups. CONCLUSIONS: Age at the time of Ross operation for primary AS does not influence long-term autograft remodeling or durability. Other physiologic or technical factors are likely greater determinants of autograft fate.

Aortic insufficiency following balloon aortic valvuloplasty does not impact long-term autograft durability after the Ross procedure.

OBJECTIVE: Preoperative aortic insufficiency (AI) is associated with inferior autograft durability after the Ross procedure. However, many patients with aortic stenosis (AS) undergo balloon aortic valvuloplasty (BAV) early and present with longstanding AI before Ross. We studied how BAV and subsequent valvular pathology impacts autograft durability. METHODS: Patients undergoing the Ross operation from 1993 to 2020 were identified. Those who underwent BAV before Ross were compared with patients who did not undergo BAV and underwent Ross for predominant AI (AI group) or AS (AS group). Those who underwent previous open surgical aortic valve intervention were excluded. Primary outcome of interest was autograft failure, defined as a composite of autograft reintervention or severe insufficiency. RESULTS: A total of 198 patients were included. Seventy-nine (39.9%) underwent BAV and subsequently underwent the Ross for predominant AI (45.6%) or AS (54.4%). Of patients who did not undergo BAV, 66 (33.3%) presented with predominant AI and 53 (26.8%) with AS. Freedom from autograft failure at 15 years was 90%, 92%, and 62% in BAV, AS, and AI groups, respectively. The AI group was at significantly increased risk of long-term autograft failure (hazard ratio, 5.6; P = .01), whereas the AS and BAV groups had similar, low risk (hazard ratio, 1.1; P = .91). Autograft durability was similar among patients who received BAV and presented with AS or AI before the Ross (P = .84). CONCLUSIONS: BAV before the Ross procedure is common in patients with AS. These patients have excellent long-term autograft durability regardless of preoperative valvular pathology and should strongly be considered for the Ross operation.

Association of post-operative ICU requirements with early extubation in the fontan procedure.

OBJECTIVES: This study investigated the association between early extubation (EE) and the degree of postoperative intensive care unit (ICU) support after the Fontan procedure, specifically evaluating the volume of postoperative intravenous fluid (IVF) and vasoactive-inotropic score (VIS). METHODS: Retrospective analysis of patients who underwent Fontan palliation from 2008 to 2018 at a single center was completed. Patients were initially divided into pre-institutional initiative towards EE (control) and post-initiative (modern) cohorts. Differences between the cohorts were assessed using t-test, Wilcoxon, or chi-Square. Following stratification by early or late extubation, four groups were compared via ANOVA or Kruskal-Wallis Test. RESULTS: There was a significant difference in the rate of EE between the control and modern cohorts (mean 42.6 versus 75.7%, p = 0.01). The modern cohort demonstrated lower median VIS (5 versus 8, p = 0.002), but higher total mean IVF (101±42 versus 82 ±27 cc/kg, p < 0.001) versus control cohort. Late extubated (LE) patients in the modern cohort had the highest VIS and IVF requirements. This group received 67% more IVF (140 ± 53 versus 84 ± 26 cc/kg, p < 0.001) and had a higher median VIS at 24 hours (10 (IQR, 5-10) versus 4 (IQR, 2-7), p < 0.001) versus all other groups. In comparison, all EE patients had a 5-point lower median VIS when compared to LE patients (3 versus 8, p= 0.001). CONCLUSIONS: EE following the Fontan procedure is associated with reduced post-operative VIS. LE patients in the modern cohort received more IVF, potentially identifying a high-risk subgroup of Fontan patients deserving of further investigation.

Aortic root translocation (Nikaidoh) procedure for complex transposition of the great arteries with left ventricular outflow tract obstruction.

Background: Several surgical techniques have been developed for the management of complex transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction (TGA/VSD/LVOTO). Aortic root translocation, or the Nikaidoh operation, offers the most anatomic biventricular repair in these patients. However, the Nikaidoh operation commonly has been limited to patients with "typical" anatomy, including a conoventricular VSD and usual coronary anatomy. We sought to describe a single surgeon's experience with aortic root translocation for complex TGA/VSD/LVOTO. Methods: We present a series of 12 patients with complex anatomy who underwent the Nikaidoh operation over the last 13 years. Results: We report good mid- to long-term results, excellent performance of the reconstructed left ventricular outflow tract, aortic valve competence, and no coronary insufficiency. Conclusions: Our experience suggests that the Nikaidoh operation is a valid option even for patients with complex TGA/VSD/LVOTO.

Trends in pediatric donor heart discard rates and the potential use of unallocated hearts for allogeneic valve transplantation.

Objectives: Allogeneic valve transplantation is an emerging therapy that delivers a living valve from a donor heart. We reviewed the national discard rate of pediatric and young adult (aged 25 years or younger) donor grafts to estimate the number of hearts potentially available to source valve allotransplantation. Methods: We queried the United Network for Organ Sharing database to identify pediatric and young adult heart donors from 1987 to 2022. Donor heart discard was defined as nontransplantation of the allograft. Results: Of 72,460 pediatric/young adult heart donations, 41,065 (56.7%) were transplanted and 31,395 (43.3%) were unutilized. The average annual number of discarded hearts in era 1 (1987-2000), era 2 (2000-2010), and era 3 (2010-2022) was 791 (42.8%), 1035 (46.3%), and 843 (41.2%), respectively. From 2017 to 2021, the average annual number of discards by age was: 39 (31.8%) neonates/infants, 78 (38.0%) toddlers, 41 (49.4%) young children, 240 (38.0%) adolescents, and 498 (40.1%) young adults. High-volume procurement regions had the greatest proportion of nonutilization, with the national average discard rate ranging from 39% to 49%. The most frequently documented reasons for nonallocation were distribution to the heart valve industry (26.5%), presumably due to suboptimal graft function, poor organ function (22.7%), and logistical challenges (10.8%). Conclusions: With ∼900 pediatric/young adult donor hearts discarded annually, unutilized grafts represent a potential source of valves for allogeneic valve transplant to supplement current conduit and valve replacement surgery. The limited availability of neonatal and infant hearts may limit this technique in the youngest patients, for whom cryopreserved homografts or xenografts will likely remain the primary valve substitute.

Chronic Medication Burden After Cardiac Surgery for Pediatric Medicaid Beneficiaries.

BACKGROUND: Congenital heart defects are the most common and resource-intensive birth defects. As children with congenital heart defects increasingly survive beyond early childhood, it is imperative to understand longitudinal disease burden. OBJECTIVES: The purpose of this study was to examine chronic outpatient prescription medication use and expenditures for New York State pediatric Medicaid enrollees, comparing children who undergo cardiac surgery (cardiac enrollees) and the general pediatric population. METHODS: This was a retrospective cohort study of all Medicaid enrollees age <18 years using the New York State Congenital Heart Surgery Collaborative for Longitudinal Outcomes and Utilization of Resources database (2006-2019). Primary outcomes were total chronic medications per person-year, enrollees per 100 person-years using ≥1 and ≥3 medications, and medication expenditures per person-year. We described and compared outcomes between cardiac enrollees and the general pediatric population. Among cardiac enrollees, multivariable regression examined associations between outcomes and clinical characteristics. RESULTS: We included 5,459 unique children (32,131 person-years) who underwent cardiac surgery and 4.5 million children (22 million person-years) who did not. More than 4 in 10 children who underwent cardiac surgery used ≥1 chronic medication compared with approximately 1 in 10 children who did not have cardiac surgery. Medication expenditures were 10 times higher per person-year for cardiac compared with noncardiac enrollees. Among cardiac enrollees, disease severity was associated with chronic medication use; use was highest among infants; however, nearly one-half of adolescents used ≥1 chronic medication. CONCLUSIONS: Children who undergo cardiac surgery experience high medication burden that persists throughout childhood. Understanding chronic medication use can inform clinicians (both pediatricians and subspecialists) and policymakers, and ultimately the value of care for this medically complex population.

Pulmonary Artery Hypoplasia in Neonates With Tetralogy of Fallot.

BACKGROUND: Neonates with symptomatic tetralogy of Fallot (sTOF) with hypoplastic pulmonary arteries (hPA) are considered high risk. Data are needed to inform the impact of hPA on outcomes, and the ideal management strategy. OBJECTIVES: The objectives of this study were to quantify the impact of hPA on outcomes in neonates with sTOF and measure the impact of strategy on pulmonary artery (PA) growth in this population. METHODS: Neonates with sTOF from 2005 to 2017 were reviewed from the Congenital Cardiac Research Collaborative. Criteria for hPA included a unilateral PA z score <-2.0 and contralateral PA z score <0. Primary outcome was mortality. Secondary outcomes included reintervention and PA growth. RESULTS: We included 542 neonates with sTOF, including 188 (35%) with hPA and 354 (65%) with normal PA, with median follow-up of 4.1 years. Median right and left hPA z scores were -2.19 (25th-75th percentile: -2.55 to -1.94) and -2.23 (25th-75th percentile: -2.64 to -1.91), respectively. Staged repair (vs primary TOF repair) was less common in the hPA cohort (36 vs 44%; P = 0.07). Survival was similar between groups (unadjusted P = 0.16; adjusted P = 0.25). Reintervention was more common in the hPA group (HR: 1.28; 95% CI: 1.01-1.63; P = 0.044); there was no difference after definitive repair (HR: 1.21; 95% CI: 0.93-1.58; P = 0.16). PA growth at 1 year was greater in the hPA cohort, particularly for the right PA (P < 0.001). CONCLUSIONS: Despite perception, the presence of hPA in neonates with sTOF conferred no increase in overall hazard of mortality or reintervention after definitive repair. PA growth was superior in the hPA cohort. These findings suggest that the presence of hPA does not adversely impact outcomes in sTOF.

The Commando procedure for pediatric patients: A case series.

Objective: The Commando procedure involves division of the intervalvular fibrous body, mitral valve replacement, and aortic valve replacement. It is considered a technically challenging procedure and traditionally has had high mortality. Methods: Five pediatric patients with combined left ventricular inflow and outflow obstruction were included in this study. Results: There were no early or late deaths during follow-up, and no pacemakers were implanted. None of the patients required reoperation during follow-up, and none developed a clinically significant gradient across the mitral valve or aortic valve. Conclusions: The risks of this operation for patients with congenital heart disease undergoing multiple redo operations should be weighed against the benefits of normal-size mitral and aortic annular diameters and dramatically improved hemodynamics.

Reduced incidence of cardiac rejection in multi-organ transplants: A propensity matched study.

BACKGROUND: Rejection remains a primary cause of graft loss after heart transplant (HT). Recognizing the immunomodulation of multi-organ transplant can enhance our understanding of the mechanisms of cardiac rejection. METHODS: This retrospective cohort study identified patients from the UNOS database with isolated heart (H, N = 37 433), heart-kidney (HKi, N = 1516), heart-liver (HLi, N = 286), and heart-lung (HLu, N = 408) transplants from 2004 to 2019. Propensity score matching reduced baseline differences between groups. Outcomes included risk of rejection prior to transplant hospital discharge and within 1 year, and mortality within 1 year of transplant. RESULTS: In the propensity score matched data, the relative risk of being treated for rejection prior to transplant hospital discharge was 61% lower for HKi (RR .39, 95% CI .29, .53) and 87% lower for HLi (RR .13, 95% CI .05, .37) compared to H. Similarly, the probability of being treated for rejection in the first year after transplant remained lower in HKi (RR .45, 95% CI .35, .57) and HLi (RR .13, 95% CI .06, .28) compared to H. The 1-year survival analysis revealed an equivalent risk of death in HKi (HR .84, 95% CI .68, 1.03) and HLi (HR 1.41, 95% CI .83, 2.41) compared to H, while HLu had a higher risk of death in the first year after transplant (HR 1.65, 95% CI 1.17, 2.33). CONCLUSIONS: Recipients of HKi and HLi experience a reduced risk of rejection when compared to H, but an equivalent risk of 1 yr mortality. These findings have important implications for the future of HT medicine.

Long-term outcomes of tricuspid valve intervention during stage 2 palliation in patients with a single right ventricle.

OBJECTIVES: In patients with single ventricle physiology and a systemic right ventricle, tricuspid valve regurgitation increases the risk of adverse outcomes, and tricuspid valve intervention at the time of staged palliation further increases that risk in the postoperative period. However, long-term outcomes of valve intervention in patients with significant regurgitation during stage 2 palliation have not been established. The purpose of this study is to evaluate the long-term outcomes after tricuspid valve intervention during stage 2 palliation in patients with right ventricular dominant circulation in a multicenter study. METHODS: The study was performed using the Single Ventricle Reconstruction Trial and Single Ventricle Reconstruction Follow-up 2 Trial datasets. Survival analysis was performed to describe the association among valve regurgitation, intervention, and long-term survival. Cox proportional hazards modeling was used to estimate the longitudinal association of tricuspid intervention and transplant-free survival. RESULTS: Patients with tricuspid regurgitation at stage 1 or 2 had worse transplant-free survival (hazard ratio, 1.61; 95% confidence interval, 1.12-2.32; hazard ratio, 2.3; 95% confidence interval 1.39-3.82). Those with regurgitation who underwent concomitant valve intervention at stage 2 were significantly more likely to die or undergo heart transplantation compared with those with regurgitation who did not (hazard ratio, 2.93; confidence interval, 2.16-3.99). Patients with tricuspid regurgitation at the time of the Fontan had favorable outcomes regardless of valve intervention. CONCLUSIONS: The risks associated with tricuspid regurgitation in patients with single ventricle physiology do not appear to be mitigated by valve intervention at the time of stage 2 palliation. Patients who underwent valve intervention for tricuspid regurgitation at stage 2 had significantly worse survival compared with patients with tricuspid regurgitation who did not.

Use of the Inspiris valve in the native right ventricular outflow tract is associated with early prosthetic regurgitation.

OBJECTIVE: The Inspiris Resilia prosthesis (Edwards Lifesciences) has been increasingly used in the pulmonic position with limited performance data. We sought to investigate its durability as a surgical pulmonary valve replacement (PVR). METHODS: We retrospectively reviewed patients who underwent PVR or conduit replacement with an Inspiris or non-Inspiris valve/conduit from 2018 to 2022. The primary end point was freedom from a composite of at least moderate pulmonary regurgitation, pulmonary stenosis, or valve/conduit reintervention. Secondary end points were individual components of the composite outcome. To account for baseline differences, propensity matching identified 70 patient pairs. RESULTS: A total of 227 patients (median age: 19.3 years [interquartile range, 11.8-34.4]) underwent PVR or conduit replacement (Inspiris: n = 120 [52.9%], non-Inspiris: n = 107 [47.1%]). Median follow-up was 26.6 months [interquartile range, 12.4-41.1]. Among matched patients, 2-year freedom from valve failure was lower in the Inspiris group (53.5 ± 9.3% vs 78.5 ± 5.9%, P = .03), as was freedom from at least moderate pulmonary regurgitation (54.2 ± 9.6% vs 86.4 ± 4.9%, P < .01). There was no difference in 2-year freedom from at least moderate pulmonary stenosis (P = .61) or reintervention (P = .92). Inspiris durability was poorer when implanted in the native right ventricular outflow tract compared with as a conduit, with 18-month freedom from valve failure of 59.0 ± 9.5% versus 85.9 ± 9.5% (P = .03). CONCLUSIONS: Early durability of the Inspiris valve is poor when implanted in the native right ventricular outflow tract; its unique design may be incompatible with the compliant pulmonary root. Modified implantation techniques or alternative prostheses should be considered.

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: Management of infants and neonates with tetralogy of Fallot.

OBJECTIVE: Despite decades of experience, aspects of the management of tetralogy of Fallot with pulmonary stenosis (TOF) remain controversial. Practitioners must consider newer, evolving treatment strategies with limited data to guide decision making. Therefore, the TOF Clinical Practice Standards Committee was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic, focused on timing and types of interventions, management of high-risk patients, technical considerations during interventions, and best practices for assessment of outcomes of the interventions. In addition, the group was tasked with identifying pertinent research questions for future investigations. It is recognized that variability in institutional experience could influence the application of this framework to clinical practice. METHODS: The TOF Clinical Practice Standards Committee is a multinational, multidisciplinary group of cardiologists and surgeons with expertise in TOF. With the assistance of a medical librarian, a citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to TOF and its management; the search was restricted to the English language and the year 2000 or later. Articles pertaining to pulmonary atresia, absent pulmonary valve, atrioventricular septal defects, and adult patients with TOF were excluded, as well as nonprimary sources such as review articles. This yielded nearly 20,000 results, of which 163 were included. Greater consideration was given to more recent studies, larger studies, and those using comparison groups with randomization or propensity score matching. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of the member votes with 75% agreement on each statement. RESULTS: In asymptomatic infants, complete surgical correction between age 3 and 6 months is reasonable to reduce the length of stay, rate of adverse events, and need for a transannular patch. In the majority of symptomatic neonates, both palliation and primary complete surgical correction are useful treatment options. It is reasonable to consider those with low birth weight or prematurity, small or discontinuous pulmonary arteries, chromosomal anomalies, other congenital anomalies, or other comorbidities such as intracranial hemorrhage, sepsis, or other end-organ compromise as high-risk patients. In these high-risk patients, palliation may be preferred; and, in patients with amenable anatomy, catheter-based procedures may prove favorable over surgical palliation. CONCLUSIONS: Ongoing research will provide further insight into the role of catheter-based interventions. For complete surgical correction, both transatrial and transventricular approaches are effective; however, the smallest possible ventriculotomy should be utilized. When possible, the pulmonary valve should be spared; and if unsalvageable, reconstruction can be considered. At the conclusion of the operation, adequate relief of the right ventricular outflow obstruction should be confirmed, and identification of a significant fixed anatomical obstruction should prompt further intervention. Given our current knowledge and the gaps identified, we propose several key questions to be answered by future research and potentially by a TOF registry: When to palliate or proceed with complete surgical correction, as well as the ideal type of palliation; the optimal surgical approach for complete repair for the best long-term preservation of right ventricular function; and the utility, efficacy, and durability of various pulmonary valve preservation and reconstruction techniques.