Young infants with symptomatic tetralogy of Fallot: Shunt or primary repair?

Objectives: The optimal treatment strategy for symptomatic young infants with tetralogy of Fallot (TOF) is unclear. We sought to compare the outcomes of staged repair (SR) (shunt palliation followed by second-stage complete repair) versus primary repair (PR) at 2 institutions that have exclusively adopted each strategy. Methods: We performed propensity score-matched comparison of 143 infants under 4 months of age who underwent shunt palliation at one institution between 1993 and 2021 with 122 infants who underwent PR between 2004 and 2018 at another institution. The primary outcome was mortality. Secondary outcomes were postoperative complications, durations of perioperative support and hospital stays, and reinterventions. Median follow-up was 8.3 years (interquartile range, 8.1-13.4 years). Results: After the initial procedure, hospital mortality (shunt, 2.8% vs PR, 2.5%; P = .86) and 10-year survival (shunt, 95%; 95% confidence interval [CI], 90%-98% vs PR, 90%; 95% CI, 81%-95%; P = .65) were similar. The SR group had a greater risk of early reinterventions but similar rates of late reinterventions. Propensity score matching yielded 57 well-balanced pairs. In the matched cohort, the SR group had similar freedom from reintervention (55%; 95% CI, 39%-68% vs 59%; 95% CI, 43%-71%; P = .85) and greater survival (98%; 95% CI, 88%-99.8% vs 85%; 95% CI, 69%-93%; P = .02) at 10 years, as the result of more noncardiac-related mortalities in the PR group. Conclusions: In symptomatic young infants with TOF operated at 2 institutions with exclusive treatment protocols, the SR strategy was associated with similar cardiac-related mortality and reinterventions as the PR strategy at medium-term follow-up.

Outcomes of extracardiac Fontan operation: A single institution experience with 398 patients.

OBJECTIVE: The study objective was to evaluate the outcomes of the extracardiac Fontan operation at a single institution. METHODS: We conducted a retrospective study of 398 patients from a single institution who underwent their initial extracardiac Fontan operation between 1997 and 2020. We determined the incidence of and risk factors for failure of the Fontan circulation, which includes death, Fontan takedown, heart transplantation, protein-losing enteropathy, plastic bronchitis, and functional status at the last follow-up. RESULTS: The median follow-up time was 10.3 years (interquartile range, 6.4-14.6). The overall survival was 96% and 86% at 10 and 20 years after extracardiac Fontan operation, respectively. There were 6 early deaths (6/398, 1.5%) and 15 late deaths (15/398, 3.8%). Forty-nine patients (12.5%) developed failure of the Fontan circulation. Freedom from the failure of Fontan circulation was 88% at 10 years and 76% at 20 years. Risk factors for failure of the Fontan circulation were right ventricular dominance (hazard ratio, 4.7; P < .001; 95% CI, 2.1-10.5), aortic atresia (hazard ratio, 5.5; P < .001; 95% CI, 2.3-12.8), and elevated mean pulmonary artery pressure (hazard ratio, 2.3; P = .002; 95% CI, 1.2-6.7). CONCLUSIONS: Rates of failure of the Fontan circulation are low after the contemporary extracardiac Fontan operation. Risk factors for failure of the extracardiac Fontan circulation include right ventricular dominance, aortic atresia, and elevated pulmonary artery pressures.

Heart Transplantation after Univentricular Palliation: Improved Outcomes and Increased Complexity.

AIM: Heart transplantation (HT) in patients with failing univentricular circulation is often challenging. This is compounded by the ever-increasing number of patients with prior Norwood-type reconstruction of the aorta, large aortic root, and often dense adhesions from multiple prior operations. We aimed to elucidate differences in outcomes of HT in patients with prior univentricular palliations, with and without prior Norwood-type aortic arch reconstruction (ArchRec). METHODS: All patients who underwent HT for failed univentricular palliation during the 1990-2022 period were included in the study. RESULTS: Of 45 patients, 18 had undergone ArchRec. Hospital mortality improved in the recent era (17.4% before 2006 vs 0% after 2006; p=0.11), despite a higher proportion of patients with ArchRec (17.4% before 2006 vs 60.8% after 2006, p=0.002). Patients with ArchRec had a higher number of prior cardiac surgeries (4.1±1.5 vs 3.2±1.3, p=0.04), longer cardiopulmonary bypass time (320±23 vs 242±21 min, p=0.02), more concomitant arch reconstruction (33.3% vs 0%, p=0.02), greater need for post-HT extracorporeal membrane oxygenation (33.3% vs 3.7%; p=0.01) and longer hospital stay (37.1±30.5 days vs 23.6±11.8 days, p=0.04). Freedom from death or retransplantation for all patients was 91%, 73%, 67%, and 53% at 1, 5, 10, and 15-years, respectively. Prior ArchRec, Fontan procedure, and earlier eras were not risk factors for death. CONCLUSIONS: The outcomes of HT after univentricular palliation have improved in recent times and low operative mortality can be achieved. Despite increased complexity, good similar outcomes can be achieved in patients with and without prior arch reconstruction regardless of the palliation stage.

Long-Term Outcomes of Mechanical Aortic Valve Replacement in Children.

When the options of aortic valve repair or the Ross procedure are not feasible or have been exhausted, mechanical aortic valve replacement (AVR) may provide a reliable and structurally durable alternative, but with the limitations of long-term anticoagulation, thrombosis risk and lack of valve growth potential. In this article, we review the longitudinal outcomes of mechanical AVR in children in our institution and compare them to those recently reported by others. From 1978 to 2020, 62 patients underwent mechanical AVR at a median age of 12.4 years (interquartile range (IQR): 8.6-16.8 years). The most common underlying diagnoses were: conotruncal anomalies (40%, 25/62), congenital aortic stenosis (16%, 10/62), rheumatic valve disease (16%, 10/62), connective tissue disease (8.1%, 5/62) and infective endocarditis (6.5%, 4/62). Thirty-two patients (52%, 32/62) had at least 1 prior aortic valve surgery prior to mechanical AVR. Early death was 3.2% (2/62). Median follow-up was 14.4 years (IQR: 8.4-28.2 years). Kaplan-Meier survival was 96.8%, 91.9%, 86.3%, and 81.9% at 1, 5, 10, and 20 years. On competing risk analysis, the proportion of patients alive without aortic valve reoperation at 1, 5, 10, and 20 years was 95.2%, 87.0%, 75.5% and 55.4%, respectively, while the proportion of patients that had aortic valve reoperation (with death as a competing event) at 1, 5, 10, and 20 years was 1.6%, 4.9%, 12.8%, and 28.5%, respectively. In conclusion, when the options of aortic valve repair or the Ross procedure are not feasible in children, mechanical AVR is an alternative, yet the long-term rates of mortality and need for aortic valve reoperation are of concern.

Outcomes of neo-aortic valve and root surgery late after arterial switch operation.

BACKGROUND: Neo-aortic root dilatation and valve regurgitation are emerging problems late after arterial switch operation (ASO). We sought to evaluate the prevalence and outcomes of neo-aortic root or valve reoperation after ASO. METHODS: All patients with biventricular circulation who underwent an ASO between 1983 and 2015 were included at a single institution. RESULTS: In our cohort of 782 late ASO survivors, the median duration of follow-up was 18.1 years (interquartile range [IQR], 11.3-25.6 years). During follow-up, 47 patients (6.0%) underwent 60 reoperations on the neo-aortic valve/root. The first neo-aortic valve/root reoperation occurred at a median of 15.2 years (IQR, 7.8-18.4 years) after ASO. Operations included mechanical Bentall (31.9%; n = 15), aortic valve repair (25.5%; n = 12), mechanical aortic valve replacement (AVR) (21.3%; n = 10), valve-sparing root replacement (19.1%; n = 9), and the Ross procedure (2.1%; n = 1). There was 1 late death (2.1%). Multivariable predictors of neo-aortic valve/root reoperation were bicuspid valve (hazard ratio [HR], 4.8; 95% confidence interval [CI], 2.1-10.7; P < .001), Taussig-Bing anomaly (HR, 3.0; 95% CI, 1.2-7.4; P < .02), previous pulmonary artery band (HR, 2.8; 95% CI, 1.2-6.3; P < .01) and left ventricular outflow tract obstruction before ASO (HR, 2.4; 95% CI, 1.0-5.8; P < .04). Freedom from neo-aortic valve or root reoperation was 98.0% (95% CI, 96.7%-98.8%) at 10 years, 93.3% (95% CI, 90.8%-95.2%) at 20 years, and 88.5% (95% CI, 84.1%-91.8%) at 30 years after ASO. Among the 47 patients who underwent neo-aortic reoperation, freedom from AVR was 82.3% (95% CI, 67.7%-90.7%) at 10 years, 58.0% (95% CI, 41.8%-71.2%) at 20 years, and 43.2% (95% CI, 27.0%-58.3%) at 25 years after ASO. CONCLUSIONS: The need for neo-aortic valve or root reoperation surpasses 10% by 30 years post-ASO. Evolving understanding of the mechanisms of neo-aortic valve insufficiency and techniques of neo-aortic valve repair may decrease the need for AVR.

Bex-Nikaidoh operation and the impact of double root translocation on outcomes.

OBJECTIVES: The Bex-Nikaidoh operation can effectively relieve left ventricular outflow tract obstruction. However, if a conduit is used for right ventricular outflow tract reconstruction, a late reoperation can be anticipated. We examined the impact of double root translocation on outcomes. METHODS: We performed a retrospective single-centre study of patients who underwent aortic root translocation between 2006 and 2019. RESULTS: Aortic root translocation was performed in 23 patients at a median age of 1.6 years [interquartile range (IQR) 0.9-2.5]. Concomitant repairs were done in 52.2% of patients (12/23) including the Senning atrial switch in 34.8% (8/23). The right ventricular outflow tract was reconstructed with valved conduits in 39.1% (9/23), direct anastomoses in 4.35% (1/23) and pulmonary autografts in 56.5% of patients (13/23). Aortic cross-clamp time was significantly longer in patients with double root translocation [308 min (IQR 270-259) vs 209 min (IQR 179-281), P = 0.02]; 2 patients in this group required temporary mechanical circulatory support. There were no early deaths. Median follow-up time was 7.5 years (IQR 3.3-10.5). The estimated 10-year survival was 90% [95% confidence interval (CI): 47.3%, 98.5%]. There was no recurrent left ventricular outflow tract obstruction. Freedom from any reoperation was 64.2% (95% CI: 40.8%, 80.3%) at 3 years and 44.5% (95% CI: 21.2%, 65.5%) at 6 years. The main indication for late reoperation was conduit degeneration. Freedom from a right ventricular outflow tract reoperation was significantly higher, and the number of reoperations per patient was lower when a double root translocation had been performed (P = 0.03). CONCLUSIONS: The Bex-Nikaidoh operation effectively relieved left ventricular outflow tract obstruction. A double root translocation further increased procedural complexity but was associated with better mid-term freedom from a right ventricular outflow tract reoperation. It should be considered in suitable patients.

Clinical assessment can be lifesaving: Salvage of catastrophic cerebral ischemia by conversion to central extracorporeal membrane oxygenation.

Peripheral veno-artertial extracorporeal membrane oxygenation (VA-ECMO) is commonly used in the paediatric population for intractable respiratory and cardiac failure. One of the devastating complications of VA-ECMO is severe brain damage due to ischemia or haemorrhage. We describe a case of peripheral cervical VA-ECMO complicated by evolving right cerebral ischemia which was rescued with rapid conversion from peripheral to central VA-ECMO support. Notably, the patient had a complete circle of Willis. Following conversion, we observed complete resolution of neurological symptoms with full functional recovery.

Long-term outcomes of tetralogy of Fallot repair: A 30-year experience with 960 patients.

OBJECTIVE: This study evaluates the long-term results of tetralogy of Fallot repair and assesses the risk factors for adverse outcomes. METHODS: This retrospective study included 960 patients who underwent transatrial transpulmonary tetralogy of Fallot repair between 1990 and 2020. RESULTS: A transannular patch was placed in 722 patients, and pulmonary valve preservation was achieved in 233 patients. The median age at tetralogy of Fallot repair was 9.4 (interquartile range, 6.2-14.2) months. The median follow-up duration was 10.6 (interquartile range, 5.4-16.3) years. There were 8 early deaths (0.8%) and 20 late deaths (2.1%). Genetic syndrome and pulmonary valve annulus Z score less than -3 were risk factors for mortality. The survival was 97.7% (95% confidence interval, 96.4-98.5) and 94.5% (95% confidence interval, 90.9-96.7) at 10 and 30 years, respectively. Freedom from any reoperation was 86.4% (95% confidence interval, 83.6-88.7) and 65.4% (95% confidence interval, 59.8-70.4) at 10 and 20 years, respectively. Postoperative right ventricular outflow tract peak gradient of 25 mm Hg or greater correlated with reoperation. Propensity score-matched analysis demonstrated that freedom from pulmonary valve replacement at 15 years was higher in the pulmonary valve preservation group compared with the transannular patch group (98.2% vs 78.4%, P = .004). Freedom from reoperation for right ventricular outflow tract obstruction at 15 years was lower in the pulmonary valve preservation group compared with the transannular patch group (P = .006). CONCLUSIONS: The long-term outcomes of tetralogy of Fallot repair are excellent. A postoperative right ventricular outflow tract peak gradient less than 25 mm Hg appears to be optimal to prevent reoperation. If the pulmonary valve size is suitable, pulmonary valve preservation reduces the risk of pulmonary valve replacement, yet increases the reoperation rate for right ventricular outflow tract obstruction.

Safety and feasibility of adjunct autologous cord blood stem cell therapy during the Norwood heart operation.

BACKGROUND: We conducted this phase I, open-label safety and feasibility trial of autologous cord blood (CB) stem cell (CBSC) therapy via a novel blood cardioplegia-based intracoronary infusion technique during the Norwood procedure in neonates with an antenatal diagnosis of hypoplastic left heart syndrome (HLHS). CBSC therapy may support early cardiac remodeling with enhancement of right ventricle (RV) function during the critical interstage period. METHODS: Clinical grade CB mononucleated cells (CBMNCs) were processed to NetCord-FACT International Standards. To maximize yield, CBSCs were not isolated from CBMNCs. CBMNCs were stored at 4 °C (no cryopreservation) for use within 3 days and delivered after each cardioplegia dose (4 × 15 mL). RESULTS: Of 16 patients with antenatal diagnosis, 13 were recruited; of these 13 patients, 3 were not treated due to placental abruption (n = 1) or conditions delaying the Norwood for >4 days (n = 2) and 10 received 644.9 ± 134 × 106 CBMNCs, representing 1.5 ± 1.1 × 106 (CD34+) CBSCs. Interstage mortality was 30% (n = 3; on days 7, 25, and 62). None of the 36 serious adverse events (53% linked to 3 deaths) were related to CBMNC therapy. Cardiac magnetic resonance imaging before stage 2 (n = 5) found an RV mass index comparable to that in an exact-matched historical cohort (n = 22), with a mean RV ejection fraction of 66.2 ± 4.5% and mean indexed stroke volume of 47.4 ± 6.2 mL/m2 versus 53.5 ± 11.6% and 37.2 ± 10.3 mL/m2, respectively. All 7 survivors completed stage 2 and are alive with normal RV function (6 with ≤mild and 1 with moderate tricuspid regurgitation). CONCLUSIONS: This trial demonstrated that autologous CBMNCs delivered in large numbers without prior cryopreservation via a novel intracoronary infusion technique at cardioplegic arrest during Norwood palliation on days 2 to 3 of life is feasible and safe.

The Ross Procedure in Children: Defining the Optimal Age.

BACKGROUND: It has been proposed that delaying the Ross procedure to later in childhood, allowing autograft stabilisation and placement of a larger pulmonary conduit, may improve outcomes. However, the effect of age at the time of Ross procedure on outcomes remains unclear. METHODS: All patients who underwent the Ross procedure between 1995 and 2018 were included in the study. Patients were divided into four groups: infants, age 1 to 5 years, age 5 to 10 years and age 10 to 18 years. RESULTS: A total of 140 patients underwent the Ross procedure in the study period. Early mortality was 23.3% (7/30) for infants compared to 0% for older children (p<0.001). Survival at 15 years was significantly lower in infants (76.3%±9.9%), compared to children aged 1 to 5 years (90.9%±20.1%), 5 to 10 years (94%±13.3%), and 10 to 18 years (86.7%±10.0%), p=0.01. Freedom from autograft reoperation at 15 years was significantly lower in infants (58.4%±16.2%), compared to children aged 1 to 5 years (77.1%±14.9%), 5 to 10 years (84.2%±6.0%) and 10 to 18 years (87.8%±9.0%), p=0.01. Overall freedom from reoperation at 15 years was 13.0%±6.0% for infants, 24.2%±9.0% for children aged 1 to 5 years, 46.7%±15.8% for children aged 5 to 10 years, and 78.4%±10.4%, p<0.001. CONCLUSIONS: The Ross procedure performed after 10 years of age appears to be associated with improved freedom from reoperation, primarily due to a reduction in reoperation on the pulmonary conduit.

Aortic valve repair versus the Ross procedure in children.

BACKGROUND: Aortic valve repair and the Ross procedure are widely used in children; however, it is unclear which provides the best outcomes. METHODS: Patients who underwent primary aortic valve surgery from 1980 to 2018 were included. Propensity score matching was performed to adjust for baseline differences. RESULTS: Of 415 children, 82.7% (343/415) underwent repair and 17.3% (72/415) underwent the Ross procedure. At 15 years, survival was higher for aortic valve repair (93.9% ± 1.8% vs 80.9% ± 6.4%, P = .04); freedom from reoperation (45.7% ± 4.9% vs 48.5% ± 9.0%, P = .29) did not differ, and freedom from aortic valve reoperation was higher in the Ross procedure group (45.7% ± 4.9% vs 70.7% ± 8.0%, P < .001). When analyzed by quality of repair, acceptable repair provided the highest survival (P = .01). Acceptable repair and the Ross procedure had similar freedom from reoperation at 15 years, whereas suboptimal repair performed worse (acceptable: 54.9% ± 6.7%; Ross procedure: 48.5% ± 9.0%; suboptimal: 27.0% ± 7.7%, P < .001). Acceptable repair and the Ross procedure had similar freedom from aortic valve reoperation at 15 years, whereas suboptimal repair showed worse results (acceptable: 54.9 ± 6.7; Ross procedure: 70.7% ± 8.0%; suboptimal: 27.0% ± 7.7%, P < .001). Propensity score matching paired 66 patients who underwent the Ross procedure with 198 patients who underwent repair. At 15 years, repair was associated with better survival (98.0% ± 1.2% vs 78.5% ± 7.2%, P = .03), whereas freedom from reoperation was similar (42.6% ± 7.6% vs 50.7% ± 9.8%, P = .50). However, the Ross procedure was associated with higher freedom from aortic valve reoperation (42.6% ± 7.6% vs 72.3% ± 8.5%, P = .002). CONCLUSIONS: Primary aortic valve repair was associated with better survival than the Ross procedure, whereas overall freedom from reoperation was similar. When an acceptable intraoperative result was achieved, outcomes of repair were favorable. However, when the intraoperative result of repair was suboptimal, the Ross procedure showed better results.

Aortic Valve Surgery in Children With Infective Endocarditis.

There is limited data on the outcomes of children who undergo surgery for aortic valve infective endocarditis (IE), and the optimal surgical approach remains controversial. We investigated the long-term outcomes of surgery for aortic valve IE in children, with a particular focus on the Ross procedure. A retrospective review of all children who underwent surgery for aortic valve IE was performed at a single institution. Between 1989 and 2020, 41 children underwent surgery for aortic valve IE, of whom 16 (39.0%) underwent valve repair, 13 (31.7%) underwent the Ross procedure, 9 (21.9%) underwent a homograft root replacement, and 3 (7.3%) underwent a mechanical valve replacement. Median age was 10.1 years (interquartile range, 5.4-14.1). The majority of children (82.9%, 34/41) had underlying congenital heart disease, while 39.0% (16/41) had previous heart surgery. Operative mortality was 0.0% (0/16) for repair, 15.4% (2/13) for the Ross procedure, 33.3% (3/9) for homograft root replacement, and 33.3% (1/3) for mechanical replacement. Survival at 10 years was 87.5% for repair, 74.1% for Ross, and 66.7% for homograft (P > 0.05). Freedom from reoperation at 10 years was 30.8% for repair, 63.0% for Ross, and 26.3% for homograft (P = 0.15 for Ross vs repair, P = 0.002 for Ross vs homograft). Children undergoing surgery for aortic valve IE have acceptable long-term survival, although the need for long-term reintervention is significant. The Ross procedure appears to be the optimal choice when repair is not feasible.

Congenital Aortic Valve Repair When the Options aren't Good: Truncus Arteriosus and Transposition of the Great Arteries.

Patients with truncus arteriosus and transposition of great arteries are prone to neo-aortic valve insufficiency. Although presenting at opposite ends of the age spectrum, both conditions tend to be commonly associated with neo aortic root dilatation. In patients with truncus arteriosus there is an additional complexity of quadricuspid valve morphology, which make up the majority of valves requiring repair. A unified approach to all these patients would include reduction and stabilization of the annulus and sinotubular junction, as well as achieving equal and symmetrical coaptation of the valve leaflets. By systematically employing these techniques, valve replacement should be avoidable in most children.

Kawashima Procedure: The Impact of Age.

BACKGROUND: The results of the Kawashima operation are incompletely defined. Furthermore, optimal timing of Kawashima operation, an important consideration when managing desaturated young infants awaiting surgery, remains unclear. We reviewed our outcomes of Kawashima operation, with a focus on the impact of age. METHODS: We conducted a retrospective review of patients who underwent Kawashima operation from 1990 to 2020. RESULTS: Thirty patients underwent Kawashima operation at a median age of 11.7 months (interquartile range, 4.4-27.4). Left isomerism was present in 27 patients (90%). There were no early deaths. There were 2 patients (6.7%) who had Kawashima takedown, both attributed to hypoxia. Fontan completion was achieved in 25 patients (83%). Overall freedom from death and transplantation at 20 years was 67% (95% CI, 32%-87%). Freedom from death and transplantation at 10 years was 100% for children 3 to 6 months of age at the time of Kawashima, compared with 86.4% for older children (P = 1.0). However, children aged 3 to 6 months had longer ventilation time (P = .01), intensive care stays (P = .03), and hospital stays (P = .05). Freedom from death or transplantation at 20 years among those who had concomitant common atrioventricular valve repair was 33%, vs 79% for those who did not undergo common atrioventricular valve repair (P = .02). CONCLUSIONS: Kawashima operation can be performed with low operative risk and acceptable long-term outcomes. Performing Kawashima operation on a patient aged less than 6 months does not affect survival, but is associated with increased morbidity. Need for common atrioventricular valve operation carries significant risk of mortality, and more effective techniques for atrioventricular valve repair are required.

Long-term Outcomes of Staged Complete Repair of Pulmonary Atresia With Ventricular Septal Defect.

BACKGROUND: The optimal strategy for pulmonary atresia with ventricular septal defect (PA-VSD) without major aortopulmonary collateral arteries is yet to be defined. It remains unclear how primary complete repair compares with staged repair. METHODS: This study reviewed the records of 107 patients with PA-VSD who were managed with systemic-to-pulmonary shunts from February 1989 to November 2019. Tables presenting summary statistics of patient and surgical data and Kaplan-Meier curves showing repair, mortality, and reoperation were created. Logistic regression analysis was performed to identify risk factors for repair, morbidity, and mortality. RESULTS: A total of 91 (85%) patients achieved complete repair at a median age of 1 year (interquartile range [IQR], 8-20 months). Survival was as follows: 97 (90%) patients at 6 months, 91 (85%) at 20 months, and 87 (81%) at 10 years. A shunt diameter of 3.5 mm or less (P = .006) and shunt after 2009 (P < .001) were associated with earlier progression to complete repair. A shunt diameter of 3.5 mm or less was an independent risk factor for interstage morbidity (hazard ratio, 4.5; IQR, 1.1-18.5; P = .039), but it was not associated with complete repair (P = .75) or mortality (P = .62). The median follow-up period was 10.5 years (IQR, 3.6-18.8 years) from birth. CONCLUSIONS: The complete repair and long-term survival rates of staged PA-VSD repair are high. The use of smaller shunts has resulted in earlier complete repair and is associated with increased risk of morbidity but not mortality.

Long-term outcomes of staged repair of tetralogy of Fallot.

BACKGROUND: The optimal management strategy for symptomatic young infants with tetralogy of Fallot (TOF) is yet to be determined. We aimed to evaluate the long-term outcomes of a staged approach with initial shunt palliation followed by complete repair. METHODS: Between January 1993 and July 2021, 160 children with TOF underwent a systemic-to-pulmonary shunt at our institution, including 65 neonates (41%). The mean duration of follow-up was 12.3 ± 8.1 years. RESULTS: Hospital mortality was 3% (4 of 160), all occurring in patients with a shunt size-to-weight ratio ≥1.2 mm/kg. Composite morbidity-defined as cardiac arrest, postoperative mechanical circulatory support, or unplanned reoperation-occurred in 21% (33 of 160). On multivariable analysis, a shunt size-to-weight ratio ≥1.2 mm/kg and prematurity were independent predictors of composite morbidity. Interstage mortality was 3% (4 of 156). A limited transannular patch was used in 75% (113 of 150) of TOF repairs. Actuarial survival at 20 years after shunt was 90% (95% confidence interval [CI], 79%-95%). Actuarial freedom from reinterventions at 20 years after TOF repair was 40% (95% CI, 28%-52%). Neonates had comparable composite morbidity, mortality, and late risk of reinterventions to older children. CONCLUSIONS: Staged repair of TOF in symptomatic young infants results in low mortality but high rates of reinterventions at long-term follow-up. A shunt size-to-weight ratio ≥1.2 mm/kg is a significant risk factor for mortality and morbidity prior to complete repair. Neonates undergoing shunt insertion have comparable outcomes to older children.