Arterial switch operation in a child with commissural malalignment and unusual coronary anatomy.

The arterial switch operation has evolved to become the treatment of choice for transposition of the great arteries and is one of the greatest success stories in congenital heart surgery. The most crucial step of the operation is the coronary artery translocation; therefore, it is of paramount importance for surgeons to know every single detail about the morphology and spatial relationships of the coronary arteries and the roots of the great vessels. However, sometimes the surgeon may face unfavourable scenarios such as major commissural malalignment and anomalous coronary artery patterns and need to be prepared to carry out a successful coronary artery translocation. Herein, we demonstrate that the trapdoor technique is useful for transferring coronary arteries in a neonate with major commissural malalignment and unusual coronary anatomy during the arterial switch operation.

The American Association for Thoracic Surgery (AATS) 2024 expert consensus document: Management of neonates and infants with Ebstein anomaly.

OBJECTIVES: Symptomatic neonates and infants with Ebstein anomaly (EA) require complex management. A group of experts was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic focusing on risk stratification and management. METHODS: The EA Clinical Congenital Practice Standards Committee is a multinational and multidisciplinary group of surgeons and cardiologists with expertise in EA. A citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to EA. The search was restricted to the English language and the year 2000 or later and yielded 455 results, of which 71 were related to neonates and infants. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of members votes with at least 75% agreement on each statement. RESULTS: When evaluating fetuses with EA, those with severe cardiomegaly, retrograde or bidirectional shunt at the ductal level, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or fetal hydrops should be considered high risk for intrauterine demise and postnatal morbidity and mortality. Neonates with EA and severe cardiomegaly, prematurity (<32 weeks), intrauterine growth restriction, pulmonary valve atresia, circular shunt, left ventricular dysfunction, or cardiogenic shock should be considered high risk for morbidity and mortality. Hemodynamically unstable neonates with a circular shunt should have emergent interruption of the circular shunt. Neonates in refractory cardiogenic shock may be palliated with the Starnes procedure. Children may be assessed for later biventricular repair after the Starnes procedure. Neonates without high-risk features of EA may be monitored for spontaneous closure of the patent ductus arteriosus (PDA). Hemodynamically stable neonates with significant pulmonary regurgitation at risk for circular shunt with normal right ventricular systolic pressure should have an attempt at medical closure of the PDA. A medical trial of PDA closure in neonates with functional pulmonary atresia and normal right ventricular systolic pressure (>20-25 mm Hg) should be performed. Neonates who are hemodynamically stable without pulmonary regurgitation but inadequate antegrade pulmonary blood flow may be considered for a PDA stent or systemic to pulmonary artery shunt. CONCLUSIONS: Risk stratification is essential in neonates and infants with EA. Palliative comfort care may be reasonable in neonates with associated risk factors that may include prematurity, genetic syndromes, other major medical comorbidities, ventricular dysfunction, or sepsis. Neonates who are unstable with a circular shunt should have emergent interruption of the circular shunt. Neonates who are unstable are most commonly palliated with the Starnes procedure. Neonates who are stable should undergo ductal closure. Neonates who are stable with inadequate pulmonary flow may have ductal stenting or a systemic-to-pulmonary artery shunt. Subsequent procedures after Starnes palliation include either single-ventricle palliation or biventricular repair strategies.

Early outcomes after post-cardiotomy extracorporeal membrane oxygenation in paediatric patients: a contemporary, binational cohort study.

OBJECTIVES: The aim of this study was to assess the early outcomes and risk factors of paediatric patients requiring extracorporeal membrane oxygenation after cardiac surgery (post-cardiotomy). METHODS: Retrospective binational cohort study from the Australia and New Zealand Congenital Outcomes Registry for Surgery database. All patients younger than 18 years of age who underwent a paediatric cardiac surgical procedure from 1 January 2013 to 31 December 2021 and required post-cardiotomy extracorporeal membrane oxygenation (PC-ECMO) in the same hospital admission were included in the study. RESULTS: Of the 12 290 patients included in the study, 376 patients required post-cardiotomy ECMO (3%). Amongst these patients, hospital mortality was 35.6% and two-thirds of patients experienced a major complication. Hypoplastic left heart syndrome was the most common diagnosis (17%). The Norwood procedure and modified Blalock-Taussig shunts had the highest incidence of requiring PC-ECMO (odds ratio of 10 and 6.8 respectively). Predictors of hospital mortality after PC-ECMO included single-ventricle physiology, intracranial haemorrhage and chylothorax. CONCLUSIONS: In the current era, one-third of patients who required PC-ECMO after paediatric cardiac surgery in Australia and New Zealand did not survive to hospital discharge. The Norwood procedure and isolated modified Blalock-Taussig shunt had the highest incidence of requiring PC-ECMO. Patients undergoing the Norwood procedure had the highest mortality (48%). Two-thirds of patients on PC-ECMO developed a major complication.

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.

Methodological optimisation of thymocyte isolation and cryopreservation of human thymus samples.

Premature lymphocytes develop into non-autoreactive, mature naïve CD4+ or CD8+ T cells in the thymus before entering the circulation. However, in-depth characterization of human thymocyte development remains challenging due to limited availability of human thymus samples and the fragile nature of thymocyte populations. Thymocytes often do not survive cryopreservation and thawing procedures, especially the fragile CD4+CD8+ double positive population. It is generally recommended to use fresh human thymus tissue on the day of excision to avoid any biases in thymocyte composition. This hampers the possibility to perform multiple experiments on the same thymus sample. To establish how the thymocyte viability and composition can be maintained, we compared two thymocyte isolation methods used for human and/or mice thymi, three cryopreservation methods in combination with our most gentle thawing technique. Based on our findings we established that fresh human thymi remain viable in cold storage for up to two days post-surgery without compromising thymocyte composition. Thymocytes can be cryopreserved if required, although the CD4+CD8+ double positive populations may be reduced. Our study provides thoroughly optimized methods to study human thymocyte development over a considerable time-frame post-surgery.

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.

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.

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.

Truncal valve repair in an adolescent with severe annular dilatation.

Approximately 20% of patients with truncus arteriosus might need a truncal valve procedure within 20 years after anatomical repair due to regurgitation. These patients commonly develop valve regurgitation due to root dilatation with a sufficient amount of good quality valvular tissue. Thus, the reduction of the truncal annulus is the single most important factor to achieve durable repair, especially in patients in whom the Ross procedure is not an option.

T-Remodeling of the Pulmonary Artery Bifurcation for Pulmonary Artery Origin Stenosis.

BACKGROUND: Various surgical techniques are utilized for reconstructing hypoplastic pulmonary arteries (PAs) in patients with conotruncal anomalies and at times, may be susceptible to restenosis and reoperation. We reviewed our experience with a simple technique of T-shaped remodeling of the PA bifurcation. METHODS: Between 2005 and 2019, 31 patients underwent T-remodeling of central PAs by a single cardiac surgeon. The PA bifurcation was opened cranially, and the opening was augmented with an oval-shaped patch effectively transforming the V-shaped bifurcation into a T-shaped bifurcation. Both origins of the PAs were enlarged, even in the instance of single PA origin stenosis. RESULTS: Median age at time of T-remodeling was 17 months (range: 7 weeks to 14 years). The following cardiac morphologies were observed: tetralogy of Fallot (n = 12, 39%), pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (n = 8, 26%), truncus arteriosus (n = 6, 19%), pulmonary atresia with VSD (n = 3, 9.7%), and transposition of the great arteries (n = 2, 6.5%). Thirteen patients (42%) had previous central shunt, and eight patients (26%) had previous modified Blalock-Taussig shunt. There were no operative mortalities. Immediately after T-remodeling, echocardiographic estimates of right ventricle to PA gradient decreased from 42 [interquartile range 28-58] mm Hg to 20 [12-36] mm Hg (P = .03). Freedom from reoperation on the PA bifurcation for the entire cohort was 100% at one year, 88% (95% CI 68%-96%) at five years and 82% (57%-93%) at ten years. CONCLUSIONS: T-remodeling for PA origin stenosis is a safe procedure with excellent freedom from reoperation that is easily reproducible and applicable to patients with all cardiac morphologies.

Aortic valve repair in a low-birth-weight neonate with poor ventricular function: staged tricuspidization of the unicuspid valve.

Congenital severe isolated aortic stenosis in neonates requires prompt intervention because left ventricular function may deteriorate rapidly. Surgical repair of a stenotic aortic valve in neonates allows debridement of fibrous material and precision commissurotomy. As such, the child would end up with a much better-quality aortic valve compared to the uncontrolled tear that results following balloon dilatation. The meticulous debridement and precise commissurotomy are important in achieving long-term durability of the aortic valve repair, with the expectation that the patient may keep the native aortic valve at least into adolescence or adulthood. If feasible, it is important to avoid placement of patches while repairing the valve, so that the growth potential of the cusps is preserved. The valve could be revisited and repaired further, so that, ideally, the native valve could be retained for life, thus avoiding aortic valve replacement entirely. We present a low-birth-weight neonate with a dysplastic unicuspid aortic valve, severe aortic valve stenosis and decreased left ventricular function who underwent repair of the aortic valve.

Outcomes of the Arterial Switch Operation in Patients With Dextrocardia.

BACKGROUND: Patients with dextrocardia and d-transposition of the great arteries (d-TGA) present a technical challenge when performing the arterial switch operation (ASO). We sought to determine the long-term outcomes of this rare presentation. METHODS: All patients who underwent the ASO with d-TGA and dextrocardia were identified from the hospital database. RESULTS: There were four patients with dextrocardia (4 of 844, 0.5%) patients; two patients had situs solitus and two patients had situs inversus. Three patients had a ventricular septal defect. Left ventricular outflow tract obstruction was present in one patient and one patient had a hypoplastic arch with severe coarctation of aorta. Anomalous coronary anatomy occurred in two patients. There was one early mortality and the cause of death was sepsis. One patient required late reoperation for severe neo-pulmonary valve regurgitation at 23 years after the ASO. At last follow-up, all three surviving patients were in New York Heart Association Class I. CONCLUSIONS: Patients with d-TGA and dextrocardia who undergo the ASO are extremely rare and require challenging operative management.