The arterial switch operation: 25-year experience with 258 patients

Simultaneous Double Balloon Dilatation for Supravalvar Pulmonary Obstruction After Arterial Switch Operation

The optimal approach for supravalvar right ventricular outflow tract obstruction(RVOTO) after arterial switch operation(ASO) is unclear. The results of percutaneous balloon dilatation have been variable. We report the results of simultaneous double balloon dilation for RVOTO after ASO. Sixteen patients (1.3(0.7-3.8) years; 9.8(8.1-15.1) kgs underwent the procedure at 14(8-44.5) months after ASO. Salient technical features included placement of balloons over stiff guide-wires positioned in both branch pulmonary arteries to enable dilation of the distal-most main pulmonary artery (MPA) with high inflation pressures (~ 12-14 atmospheres) and short inflation-deflation cycles. Effective balloon size was based on the PA annulus or MPA distal to the narrowing. The final balloon: narrowest segment diameter ratio was 2.7. Following dilation, the right ventricle to systemic systolic pressure ratio decreased from 0.9 ± 0.18 to 0.52 ± 0.16 (p  < 0.001) and mean RVOT gradient from 78 ± 18 to 34 ± 13.9 mmHg (p < 0.001). Narrowest diameter improved from 5.4 ± 2.2 to 9.2 ± 2.2 mm. There were no major complications. Two patients with inadequate relief (final RV-systemic ratios: 1.03 and 0.7) were referred for surgery. At median follow up of 9 months, IQR 7-22, range 5-73, others are free of re interventions with median RVOT gradient of 42, IQR 27-49, range 21-55 mmHg. The immediate and short-term follow up results of double balloon dilatation for supravalvar RVOTO is encouraging and may avoid the need for repeat surgery in the majority of patients. Further follow up is needed to determine the long-term durability of the results.

Pathogenesis and Surgical Treatment of Dextro-Transposition of the Great Arteries (D-TGA): Part II

Dextro-transposition of the great arteries (D-TGA) is the second most common cyanotic heart disease, accounting for 5-7% of all congenital heart defects (CHDs). It is characterized by ventriculoarterial (VA) connection discordance, atrioventricular (AV) concordance, and a parallel relationship with D-TGA. As a result, the pulmonary and systemic circulations are separated [the morphological right ventricle (RV) is connected to the aorta and the morphological left ventricle (LV) is connected to the pulmonary artery]. This anomaly is included in the group of developmental disorders of embryonic heart conotruncal irregularities, and their pathogenesis is multifactorial. The anomaly's development is influenced by genetic, epigenetic, and environmental factors. It can occur either as an isolated anomaly, or in association with other cardiac defects. The typical concomitant cardiac anomalies that may occur in patients with D-TGA include ventriculoseptal defects, patent ductus arteriosus, left ventricular outflow tract obstruction (LVOTO), mitral and tricuspid valve abnormalities, and coronary artery variations. Correction of the defect during infancy is the preferred treatment for D-TGA. Balloon atrial septostomy (BAS) is necessary prior to the operation. The recommended surgical correction methods include arterial switch operation (ASO) and atrial switch operation (AtrSR), as well as the Rastelli and Nikaidoh procedures. The most common postoperative complications include coronary artery stenosis, neoaortic root dilation, neoaortic insufficiency and neopulmonic stenosis, right ventricular (RV) outflow tract obstruction (RVOTO), left ventricular (LV) dysfunction, arrhythmias, and heart failure. Early diagnosis and treatment of D-TGA is paramount to the prognosis of the patient. Improved surgical techniques have made it possible for patients with D-TGA to survive into adulthood.

Neurodevelopment outcomes in the first 5 years of the life of children with transposition of the great arteries surgically corrected in the neonatal period: systematic review and meta-analysis

OBJECTIVES

In patients with transposition of the great arteries, surgical correction may achieve definitive treatment, so a thorough knowledge of the long-term outcomes, particularly neurodevelopment outcomes, is essential. Therefore, we conducted a systematic review and meta-analysis to study the neurodevelopment outcomes in the first 5 years of the life of children submitted to corrective surgery for transposition of the great arteries in the neonatal period.

METHODS

A total of 17 studies from 18 reports were included, assessing 809 individuals with surgically corrected transposition of the great arteries. The neurodevelopmental outcomes were assessed with the Bayley Scales of Infant and Toddler Development (BSID) and the Wechsler Intelligence Scale for Children (WISC).

RESULTS

Mean Mental Development Index (MDI) and Psychomotor Development Index (PDI) were within the average values from 1 to 3 years of age, although the proportion of children scoring more than 1 standard deviation below the mean in PDI, MDI, motor, and language composite scores was significantly higher than in the general population. From 4 to 5 years, mean full-scale global intelligence quotient (IQ), verbal IQ, and performance IQ scores did not differ significantly from the general population.

CONCLUSION

This study revealed neurodevelopment scores within the normal range at 5 years of age in children submitted to corrective surgery for transposition of the great arteries in the neonatal period. However, these early outcomes may not adequately predict long-term outcomes. Further studies are needed to identify specific risk factors and early markers of later impairment to guide the establishment of early interventions.

Valve-Sparing Neo-Aortic Root Replacement for Neo-Aortic Root Dilatation 20 Years after Arterial Switch Operation for Transposition of the Great Arteries: A Case Report

A 25-year-old man returned to Seoul National University Children's Hospital with mild dyspnea on exertion. He had undergone an arterial switch operation at 1 month after birth to correct a complete transposition of the great arteries and a ventricular septal defect. When the patient was 15 years old, dilatation of the neo-aortic sinus and annulus was first identified; since then, it had gradually increased. Given the young age of the patient and the degree of aortic regurgitation (AR), which was mild to moderate, we opted to perform a valve-sparing neo-aortic root replacement with aortic valve repair. Postoperative echocardiography showed successful reductions in the sizes of the aortic sinus and annulus, with only mild AR remaining.

Inattention and hyperactivity in children and adolescents with repaired D-transposition of the great arteries: Prevalence, perioperative risk factors, and clinical outcomes

Objective

The present study objectives were to determine the prevalence of attention-deficit/hyperactivity disorder symptoms (ADHD-like symptoms) in children and adolescent with d-transposition of great artery (D-TGA) after arterial switch operation (ASO) and examine associated risk factors and adverse personal, family dysfunctions.

Methods

This cohort study included 103 patients with D-TGA who underwent ASO in early infancy at Shanghai Children’s Medical Center between 2011 and 2016 and then follow-up. Data analysis was conducted from September 2020 to April 2022. A standardized Swanson, Nolan, and Pelham IV (SNAP-IV) questionnaire is used to evaluate inattention and hyperactivity symptoms. Demographic, preoperative, intraoperative, and postoperative factor were collected. Univariate and multivariable regression analyses were performed with odds ratios (OR) and 95% confidence intervals (CIs).

Results

Prevalence of ADHD-like symptoms was 27.18% (28/103). Attention-deficit (18/28, 64.29%) symptom was the predominant subphenotype. After underwent TGA surgery, 39% of patients with ADHD-like symptoms receive remedial special academic services. There is none had repeated grade. Univariate analysis showed that, positive inotropic drug score (P = 0.03) and delayed sternal closure (P = 0.02) were risk factors of ADHD-like symptoms; increased preoperative oxygen saturation (SpO2) (P = 0.01) and surgical height (P = 0.01) and TGA subtype (VSD) (P = 0.02) were protective factor of ADHD-like symptoms. Multivariable analysis showed that delayed sternal closure (DSC) (OR, 1.50; 95% CI, 1.02–2.18) is a risk factor for the occurrence of ADHD-like symptom while increased preoperative oxygen saturation [odds ratio (OR), 0.95; 95% confidence interval (CI), 0.92–0.99] is a protective factor of ADHD-like symptom.

Conclusion

The children and adolescents with D-TGA after ASO were at high risk of ADHD-like symptoms. Preoperative hypoxic status and postoperative DSC became predominant risk factors. Modification of the risk factors may be helpful to relieve ADHD-like symptoms for these patients.

Nine-Year Experience with the Arterial Switch Operation with Closed Coronary Transfer

BACKGROUND

Coronary artery transfer is a critical step of the arterial switch operation (ASO) for transposition of the great arteries (TGA). Strategies for coronary transfer include open transfer before neo-aortic anastomosis or closed transfer after neo-aortic anastomosis. This study reports outcomes of ASO with closed coronary transfer at a single institution.

METHODS

A retrospective analysis was performed of patients undergoing ASO for TGA from November 2006 to September 2015. Closed coronary transfer was universally employed. Patients were classified into simple versus complex coronary anatomy groups. The primary outcome was overall survival. Secondary outcomes included reoperation-free survival, coronary re-intervention, and aortic insufficiency.

RESULTS

Ninety-six consecutive patients underwent ASO for TGA. Median follow-up was 5.8 years. Thirty-five (36%) of patients had complex coronary anatomy, which was associated with significantly longer cardiopulmonary bypass and aortic cross-clamp time. Overall survival was 97.4%, and reoperation-free survival was 83.6%. There was no difference in survival or reoperation-free survival between patients with simple versus complex coronary anatomy. Hispanic ethnicity, side-by-side great arteries, and urgent or emergent operation were significantly associated with the composite outcome of reoperation or mortality. There were no coronary interventions after ASO, and the incidence of moderate or greater aortic insufficiency was 2.1% at hospital discharge and 1.5% in follow-up.

CONCLUSIONS

Closed coronary transfer during ASO has excellent short and mid-term results. Despite variable and often complex coronary anatomy, coronary ischemic events following ASO are avoidable. Closed coronary transfer has a low risk of aortic valve injury or insufficiency.

The Coronary Arteries in Adults after the Arterial Switch Operation: A Systematic Review

Coronary artery status in adults long after the arterial switch operation (ASO) is unclear. We conducted a systematic review to provide an overview of coronary complications during adulthood and to evaluate the value of routine coronary imaging in adults after ASO, in light of current guidelines. Articles were screened for the inclusion of adult ASO patients and data on coronary complications and findings of coronary imaging were collected. A total of 993 adults were followed with a median available follow-up of only 2.0 years after reaching adulthood. Myocardial ischemia was suspected in 17/192 patients (8.9%). The number of coronary interventions was four (0.4%), and coronary death was reported in four (0.4%) patients. A lack of ischemia-related symptoms cannot be excluded because innervation studies indicated deficient cardiac innervation after ASO, although data is limited. Anatomical high-risk features found by routine coronary computed tomography (cCT) included stenosis (4%), acute angle (40%), kinking (24%) and inter-arterial course (11%). No coronary complications were reported during pregnancy (n = 45), although, remarkably, four (9%) patients developed heart failure. The 2020 European Society of Cardiology (ESC) guidelines state that routine screening for coronary pathologies is questionable. Based on current findings and in line with the 2018 American ACC/AHA guidelines a baseline assessment of the coronary arteries in all ASO adults seems justifiable. Thereafter, an individualized coronary follow-up strategy is advisable at least until significant duration of follow-up is available.

Growth Pattern of the Neo-Aorta after Arterial Switch Operation during Childhood

Background and Objectives

Neo-aortic root dilatation (ARD) and annular dilatation (AAD) tend to develop after arterial switch operation (ASO). However, the trend of neo-aortic growth has not been well established. This paper aims to identify this trend, its associated factors, and predictors of neo-aortic dilatation after ASO.

Methods

We analyzed the growth trend of the neo-aortic root, annulus, and sinotubular junction (STJ) z-scores using random coefficients model and the risk factors affecting neo-aortic dilatation in 163 patients who underwent ASO from 2006 to 2015.

Results

Among 163 patients, 41 had a ventricular septal defect, and 11 had Taussig-Bing (TB) anomaly. The median follow-up duration was 6.61 years. The increased in the neo-aortic root z-score was different between the trapdoor and non-trapdoor coronary artery transfer techniques (0.149/year, p<0.001 vs. 0.311/year, p<0.001). Moreover, the neo-aortic annulus and STJ z-score significantly increased over time after ASO (0.067/year, p<0.001; 0.309/year, p<0.001). Pulmonary artery banding (PAB) was rather a negative affecting factor. The probabilities of freedom from ARD, AAD, and neo-aortic STJ dilatation at 10 years after ASO were 33.4%, 53.9%, and 65.4%. Neo- aortic regurgitation within 1 year was the predictor of ARD, AAD, and neo-aortic STJ dilatation. TB anomaly, PAB, and native pulmonary sinus z-score were other predictors for ARD.

Conclusion

The growth of neo-aortic root, annulus, and STJ after ASO was greater than somatic growth during childhood. The coronary artery transfer technique affected the growth pattern of the neo-aortic root.

The behavior of residual pulmonary artery gradient after arterial switch operation: A longitudinal data analysis

OBJECTIVE

The arterial switch operation (ASO) is the standard treatment for the transposition of the great arteries. The timely variation in the residual pressure gradient across the pulmonary arteries is ill-defined. This study is aimed to study the progressive changes in the pressure gradient across the pulmonary valve and pulmonary arteries after ASO.

METHODS

All eligible patients for this study who underwent ASO between 2000 and 2019 were reviewed. Transthoracic echocardiography was used to estimate the peak pressure gradient across the pulmonary artery and its branches. The primary outcome was the total peak pressure gradient (TPG) which is the sum of peak pressure gradients across the main pulmonary artery and pulmonary artery branches. Furthermore, longitudinal data analyses with mixed-effect modeling were used to determine the independent predictors for the changes in the pressure gradient.

RESULTS

Three hundred and nine patients were included in the study. Over a 17-year follow-up, the freedom from pulmonary stenosis reintervention was 95% (16 out of the 309 patients underwent reintervention = 5%). The longitudinal data analyses of serial 1844 echocardiographic studies for the included patients revealed that the TPG recorded in the first postoperative echocardiogram across pulmonary valve, right and left pulmonary artery branches was the most significant predictor for reintervention.

CONCLUSION

The total peak gradient measured in the first postoperative echocardiogram is the most important predictor for reintervention. We propose that a total peak gradient in the first postoperative echocardiography of 55 mm Hg or more is a predictor for reintervention.

Modified Closed Coronary Transfer is a Good Alternative to the Trap-Door Method During Arterial Switch Operation: a Retrospective Propensity-Matched Comparison

Objective

To compare the early and long-term results of patients in whom was performed modified closed coronary transfer with the results of patients in whom was performed trap-door transfer techniques by utilizing propensity-matching analysis to provide optimal identical patient matching for the groups.

Methods

From August 2015 to December 2017, 127 consecutive patients underwent arterial switch operation due to simple and complex transposition of the great arteries, with or without additional arch and complex coronary pattern, by a single surgical team included into the study. Of these, in 70 patients it was performed modified closed coronary transfer technique and in 57 patients it was performed trap-door style coronary transfer technique. The patients were divided into two groups in terms of coronary transfer method. In the final model, after propensity matching, 47 patients from each group having similar propensity score were included into the study.

Results

There was no significant difference between the groups regarding patient characteristics. Cross-clamp time and operation time were significantly lower in the modified technique group compared with the other group (P=0.03 and P=0.05, respectively). When compared the early and late postoperative outcomes, there was no significant difference between the groups. Postoperative echocardiographic findings were mostly similar between the groups.

Conclusion

The patients in whom was performed our modified technique demonstrate overall good outcomes and the current technique ensures shorter arterial cross-clamp and operation times. It may be an alternative method to the trap-door technique for the coronary transfer during the arterial switch operation.

Identifying Subclinical Coronary Abnormalities and Silent Myocardial Ischemia After Arterial Switch Operation

The incidence of late coronary complications is reported around 8% after arterial switch operation (ASO) for d-transposition of the great arteries, but the affected patients are usually asymptomatic. Exercise stress test (EST) and myocardial perfusion imaging (MPI) are common non-invasive modalities to screen for silent myocardial ischemia, but their diagnostic reliability in children after ASO is unclear. We retrospectively reviewed asymptomatic patients following ASO with EST, MPI, and coronary imaging studies (CIS) and examined the reliability of each test in identifying abnormal coronary lesions responsible for myocardial ischemia. Thirty-seven asymptomatic patients (24 males; ages 12.7 ± 3.7 years) had EST, in which 27 and 33 patients also underwent MPI and CIS, respectively. Exercise capacity was comparable to the age- and sex-matched 37 controls. In seven patients with angiographically proven moderate to severe coronary abnormalities, only two patients had positive EST and/or MPI, and five patients were negative including one patient who later developed exercise-induced cardiac arrest due to severe proximal left coronary artery stenosis. Two patients with positive EST or MPI showed no corresponding coronary abnormalities by CIS. Occurrence of acquired late coronary abnormalities did not correlate with the original coronary anatomy or initial surgical procedures. There is no single reliable method to identify the risk of myocardial ischemia after ASO. Although CIS are regarded as a gold standard, multidisciplinary studies are essential to risk-stratify the potential life-threatening coronary lesions after ASO in children.

Modified Coronary Reimplantation for Small Aortic Root Replacement Mismatch

Coronary reimplantation is a key step of aortic root replacement and may present special challenges under specific circumstances. Particularly in reoperations, mobilization of the coronary ostia can be hazardous and reattachment may require one or more interposition grafts to avoid tension, as originally described by Cabrol. We report a modified reimplantation technique of the coronary arteries that allows the creation of wide neo-ostia with minimal prosthetic material in case of a small aortic root.

Identification of coronary artery anatomy on dual-source cardiac computed tomography before arterial switch operation in newborns and young infants: comparison with transthoracic echocardiography

BACKGROUND

Considering inherent limitations of transthoracic echocardiography, the diagnostic accuracy of cardiac CT in identifying coronary artery anatomy before arterial switch operation needs to be investigated with recently improved coronary artery visibility using electrocardiogram (ECG)-synchronized dual-source CT.

OBJECTIVE

To compare diagnostic accuracy between cardiac CT using a dual-source scanner and transthoracic echocardiography in identifying coronary artery anatomy before arterial switch operation in newborns and young infants.

MATERIALS AND METHODS

The study included 101 infants (median age 4 days, range 0 days to 10 months; M:F=78:23) who underwent ECG-synchronized cardiac dual-source CT and transthoracic echocardiography before arterial switch operation between July 2011 and December 2016. We evaluated and classified coronary artery anatomy on cardiac CT and transthoracic echocardiography. With the surgical findings as the reference standard, we compared the diagnostic accuracy for identifying coronary artery anatomy between cardiac CT and transthoracic echocardiography.

RESULTS

The most common coronary artery pattern was the usual pattern (left coronary artery from sinus 1 and right coronary artery from sinus 2; 64.4%, 65/101), followed by a single coronary artery from sinus 2 and a conal branch from sinus 1 (7.9%, 8/101), the inverted pattern (5.9%, 6/101), the right coronary artery and left anterior descending artery from sinus 1 and the left circumflex artery from sinus 2 (5.9%, 6/101), and others. In 96 infants with surgically proven coronary artery anatomy, the diagnostic accuracy of cardiac CT was significantly higher than that of transthoracic echocardiography (91.7%, 88/96 vs. 54.2%, 52/96; P<0.0001).

CONCLUSION

Diagnostic accuracy of cardiac CT is significantly higher than that of echocardiography in identifying coronary artery anatomy before arterial switch operation in newborns and young infants.

Early and mid-term follow-up of patients receiving arterial switch operation: a single-center experience

Background

The arterial switch operation (ASO) has become the preferred method for surgical correction of transposition of the great arteries (TGA) and Taussig-Bing anomaly. This study was aimed to analysis the early and mid-term results of patients receiving ASO for TGA and Taussig-Bing anomaly in our institute.

Methods

A single-institution retrospective study was conducted to assess cardiovascular outcomes after ASO between January 2007 and December 2013. A total of 119 consecutive patients were included in this study. The median age at operation was 30 days (range, 1 day-8 years), the median weight was 3.8 kg (range, 2.0-23.0 kg). The ventricular septum was intact in 59 (49.6%) patients, 43 (36.1%) had ventricular septal defect, and 17 (14.3%) had a Taussig-Bing anomaly. We followed up patients with echocardiography. Special attention had been paid to the neo-aortic regurgitation and pulmonary stenosis.

Results

In hospital deaths occurred in 10 (8.4%) patients. The most cause of death was low cardiac output due to deconditioning of the left ventricle and myocardial infarction. Echocardiographic data after ASO were collected in 93 (85.3%) patients at a mean duration of 60.7±20.2 months. Among them, 4 (4.3%) patients had moderate to severe neo-aortic regurgitation, 1 (1.1%) patient had moderate tricuspid regurgitation, 4 (4.3%) patients had moderate pulmonary regurgitation; 1 (1.1%) patients had moderate pulmonary stenosis and no patients had severe stenosis. Only two patients required a surgical reintervention.

Conclusions

The early mortality rate has decreased and the most cause of death was low cardiac output. The outcomes of the ASO using our reconstruction and reimplantation techniques were excellent and the reoperation rate was very low in the early and mid-term follow-up.

Development of quality metrics for ambulatory pediatric cardiology: Transposition of the great arteries after arterial switch operation

OBJECTIVE

To develop quality metrics (QMs) for the ambulatory care of patients with transposition of the great arteries following arterial switch operation (TGA/ASO).

DESIGN

Under the auspices of the American College of Cardiology Adult Congenital and Pediatric Cardiology (ACPC) Steering committee, the TGA/ASO team generated candidate QMs related to TGA/ASO ambulatory care. Candidate QMs were submitted to the ACPC Steering Committee and were reviewed for validity and feasibility using individual expert panel member scoring according to the RAND-UCLA methodology. QMs were then made available for review by the entire ACC ACPC during an "open comment period." Final approval of each QM was provided by a vote of the ACC ACPC Council.

PATIENTS

Patients with TGA who had undergone an ASO were included. Patients with complex transposition were excluded.

RESULTS

Twelve candidate QMs were generated. Seven metrics passed the RAND-UCLA process. Four passed the "open comment period" and were ultimately approved by the Council. These included: (1) at least 1 echocardiogram performed during the first year of life reporting on the function, aortic dimension, degree of neoaortic valve insufficiency, the patency of the systemic and pulmonary outflows, the patency of the branch pulmonary arteries and coronary arteries, (2) neurodevelopmental (ND) assessment after ASO; (3) lipid profile by age 11 years; and (4) documentation of a transition of care plan to an adult congenital heart disease (CHD) provider by 18 years of age.

CONCLUSIONS

Application of the RAND-UCLA methodology and linkage of this methodology to the ACPC approval process led to successful generation of 4 QMs relevant to the care of TGA/ASO pediatric patients in the ambulatory setting. These metrics have now been incorporated into the ACPC Quality Network providing guidance for the care of TGA/ASO patients across 30 CHD centers.

Left-Sided Reoperations After Arterial Switch Operation: A European Multicenter Study

BACKGROUND

We sought to report the frequency, types, and outcomes of left-sided reoperations (LSRs) after an arterial switch operation (ASO) for patients with D-transposition of the great arteries (D-TGA) and double-outlet right ventricle (DORV) TGA-type.

METHODS

Seventeen centers belonging to the European Congenital Heart Surgeons Association (ECHSA) contributed to data collection. We included 111 patients who underwent LSRs after 7,951 ASOs (1.4%) between January 1975 and December 2010. Original diagnoses included D-TGA (n = 99) and DORV TGA-type (n = 12). Main indications for LSR were neoaortic valve insufficiency (n = 52 [47%]) and coronary artery problems (CAPs) (n = 21 [19%]).

RESULTS

Median age at reoperation was 8.2 years (interquartile range [IQR], 2.9-14 years). Seven patients died early after LSRs (6.3%); 4 patients with D-TGA (5.9%) and 3 patients with DORV TGA-type (25%) (p = 0.02). Median age at last follow-up was 16.1 years (IQR, 9.9-21.8 years). Seventeen patients (16%) required another reoperation, which was more frequent in patients with DORV- TGA type (4 of 9 [45%]) than in patients with D-TGA (13 of 95 [14%]). Late death occurred in 4 patients (4 of 104 [3.8%]). The majority of survivors were asymptomatic at last clinical examination (84 of 100 [84%]).

CONCLUSIONS

Reoperations for residual LSRs are infrequent but may become necessary late after an ASO, predominantly for neoaortic valve insufficiency and CAPs. Risk at reoperation is not negligible, and DORV TGA-type anatomy, as well as procedures on the coronary arteries, were significantly associated with a higher morbidity and a lower overall survival. Recurrent reoperations after LSRs may be required.

Transposition of Great Arteries with Complex Coronary Artery Variants: Time-Related Events Following Arterial Switch Operation

Coronary artery anatomy represents a challenging and, often, determining predictor of outcome in an arterial switch operation (ASO). Impact of specific coronary artery variants, such as single, intramural and inverted, on time-related events following ASO, is, yet, to be determined. We sought to compare early and late outcomes within the group of nonstandard coronary artery variants. Patients who underwent ASO from January 1995 to October 2010 were reviewed. Patients with coronary artery variants other than L1Cx1R2 ("standard" by Leiden classification) were included. Patients with single, intramural and inverted coronary artery variants incorporated in group A. All other nonstandard coronary variants incorporated in group B. Demographics, perioperative variables, early and late outcomes were assessed. Of the 123 ASO, 24 patients (19.5%) with nonstandard coronary variant were studied. Thirteen were in group A and 11 in group B. There were two early deaths (1 in group A and 1 in group B) (p > 0.05). There is one death early after hospital discharge (group A). Mean follow-up was 59.4 ± 55.1 months. There was no structural coronary artery failure after hospital discharge following ASO. Freedom from any reintervention at 8 years was (78.3 ± 9.6%) (p 0.55) with no late neo-aortic or mitral valve intervention. ASO with single, intramural or inverted coronary artery course carries no added longitudinal risk for structural or flow impairment within the group of nonstandard coronary artery variants. There is an early hazard period with no late survival attrition. Aortic arch repair as part of staged strategy prior to ASO might influence early and late outcome.

Coronary artery problems late after arterial switch operation for transposition of the great arteries

BACKGROUND

The incidence of late coronary artery abnormalities after arterial switch operation (ASO) for d-loop transposition of the great arteries may be underestimated.

METHODS AND RESULTS

We retrospectively reviewed coronary artery morphology in 40 of 97 patients who survived the first year after ASO. Seven asymptomatic patients developed significant late coronary artery abnormalities. One patient died suddenly at home with severe left coronary artery (LCA) ostial stenosis at age 3.8 years. The second patient collapsed during exercise at age 9.6 years due to ventricular fibrillation and severe LCA ostial stenosis despite prior negative exercise stress test (EST) and myocardial perfusion imaging (MPI). The third patient was found to have moderate ostial stenosis of the LCA with negative EST and MPI. The fourth patient with exercise-induced ST-T depression and myocardial perfusion defect was shown to have complete LCA occlusion with collateral vessel formation. Three other patients had complete proximal obliteration of either of the coronary arteries with collateral supply. An additional 4 asymptomatic patients had trivial-mild narrowing of the LCA on routine selective coronary angiogram.

CONCLUSIONS

Incidence of late coronary stenosis or occlusion was not infrequent after ASO (11.3%) and presented usually without preceding symptoms and often after negative non-invasive screening. We advocate routine coronary imaging in all patients after ASO before they participate in competitive sports.

Anesthetic Considerations and Management of Transposition of the Great Arteries

Transposition of the great arteries was once an almost uniformly fatal disease in infancy. Six decades of advances in surgical techniques, intraoperative care, and perioperative management have led to at least 90% of patients reaching adulthood, most with a good quality of life. This review summarizes medical and surgical decision making during the neonatal perioperative period, with a special emphasis on factors pertinent to the anesthetic evaluation and care during primary surgical repair of transposition of the great arteries. A review is also provided of anesthetic considerations for noncardiac surgery later in childhood or adulthood, for those survivors of the arterial switch operation, Rastelli procedure, Nikaidoh procedure, and the réparation á l’étage ventriculaire procedure.

Transposition of the great arteries--outcomes and time interval of early neonatal repair

BACKGROUND

This study evaluates the relationship of morbidity and resource utilization with the timing of early neonatal repair of transposition of the great arteries and intact ventricular septum (d-TGA/IVS).

METHODS

All patients with d-TGA/IVS who underwent arterial switch in the first 14 days of life, between January 2000 and May 2011, were reviewed. Patients undergoing repair at ≤ 4 days of age were categorized as group I, 5 to 7 days as group II, and 8 to 14 days as group III. Outcomes included mortality, morbidity, and resource utilization.

RESULTS

Hospital survival was 69 (98.6%) of 70. The length of stay (LOS) and total charges were lowest in group I--15.5 days compared to group II--18.0 days and group III--23.5 days (P = .005); group I--US$128,219 compared to group II--US$141,729 and group III--US$217,427 (P = .0006). Using regression analysis to account for potentially confounding effects of multiple variables and treating time as a continuous variable demonstrated that age at surgery was significantly associated with total LOS (P = .029), hospital charges (P = .029) and intensive care unit charges (P = .002). Younger age at repair was not associated with worse outcomes for any measure of morbidity.

CONCLUSIONS

Earlier repair of d-TGA/IVS was associated with decreased resource utilization and no detriment to clinical outcomes. Further analysis based on a larger cohort of patients is needed to verify these results that have important implications for improving the value of care.

Long-term follow-up assessment after the arterial switch operation for correction of dextro-transposition of the great arteries by means of exercise myocardial perfusion-gated SPECT

The arterial switch operation (ASO) is the preferred technique for correcting transposition of the great arteries, but translocation and reimplantation of the coronary arteries can produce myocardial ischemia. This report aims to describe the authors' experience with exercise single-photon emission computed tomography (SPECT) used to evaluate myocardial perfusion. Exercise-rest gated-myocardial perfusion SPECT was performed for 69 patients (49 boys; median age, 9 years; 5th percentile [6.4 years] to 95th percentile [15.6 years]), 64 of whom were asymptomatic 9.98 ± 3.20 years after ASO. During exercise testing, the patients reached 9.85 ± 3.05 metabolic equivalents (METs) and a median heart rate of 160 beats per minute (bpm), 5th percentile (106 bpm) to 95th percentile (196 bpm). Whereas 61 patients (88.41 %) had normal myocardial perfusion, 2 patients (2.9 %) had reversible defects, and 6 patients (8.7 %) had fixed defects. All the patients with perioperative ischemic complications (4/4, 100 %) had myocardial perfusion defects, whereas four patients (4/65, 6.15 %) without ischemic complications had abnormal perfusion (p = 0.0005). Age at the time of surgery did not differ significantly (p = 0.234) between the patients with perfusion defects and those with normal study results. No significant difference was observed between the patients who had an A coronary pattern (left coronary artery originating from the left sinus and the right coronary artery originating from the right sinus, n = 47) and those who had a non-A coronary pattern (n = 22) (p = 1). The high rate for normality of exercise myocardial perfusion in our study suggests that myocardial perfusion gated-SPECT should be reserved for patients who have experienced perioperative ischemic complications or those with symptoms, at least during the first 10 years after the surgery.

The neoaortic root in children with transposition of the great arteries after an arterial switch operation

OBJECTIVES

Neoaortic root changes in children with transposition of the great arteries (TGA) are reportedly risk factors for the development of neoaortic regurgitation (NeoAR). The aims of this study were to assess the neoaortic root diameter and relative proportion in children with TGA after surgical correction and to identify possible correlations with the development of neoaortic insufficiency.

METHODS

Of the 611 children who had the arterial switch operation performed in the Cardiology Department of the Polish Mother's Memorial Hospital, 172 consecutive patients were qualified for this study. The inclusion criteria were: anatomical correction performed during the neonatal period, more than 10 years of postoperative observation and at least two full echocardiographic examinations.

RESULTS

NeoAR increased during postoperative follow-up and at the end of the observation period, 76% of the patients had NeoAR (27%-trace, 42%-mild, 7%-moderate and 0.6%-severe). Among the analysed risk factors for NeoAR development, the significant ones were arterial valve discrepancy (OR = 2.05; 95% CI: 1.04-4.02; P = 0.031) and the non-facing commissures (OR = 4.05; 95% CI: 1.34-11.9; P = 0.01). The neoaortic root diameter was not statistically significantly correlated with the presence of NeoAR or with the heart defects associated with transposition. The neoaortic root was initially, on average, 37% (z-score = 1.58) bigger than the aortic root in healthy children. This disproportion increased during the follow-up evaluations to 57% (z-score = 2.09).

CONCLUSIONS

The neoaortic root in children after the arterial switch procedure develops differently from that in healthy children, but this is not evidently related to NeoAR development or associated heart defects.

Long-term outcomes of the neoaorta after arterial switch operation for transposition of the great arteries

BACKGROUND

After the arterial switch operation (ASO) for transposition of the great arteries (TGA), the native pulmonary root and valve function in the systemic position, and the long-term risk for neoaortic root dilation and valve regurgitation is currently undefined. The aim of this study was to determine the prevalence and progression of neoaortic root dilation and neoaortic valve regurgitation in patients with TGA repaired with the ASO.

METHODS

Measurements of the neoaortic annulus, neoaortic root at the level of the sinuses of Valsalva, and the degree of neoaortic regurgitation were assessed by serial transthoracic echocardiograms on 124 patients with TGA at a median follow-up of 7.2 years (range, 1 to 23 years) after the ASO at our institution.

RESULTS

Neoaortic root dilation with z scores of 2.5 or greater was identified in 66%, and the root diameter z score increased at an average rate of 0.08 per year over time after ASO. Freedom from neoaortic root dilation at 1, 5, 10, and 15 years after ASO was 84%, 67%, 47%, and 32%, respectively. Risk factors for root dilation include history of double-outlet right ventricle (p = 0.003), previous pulmonary artery banding (p = 0.01), and length of follow-up (p = 0.04). Neoaortic valve regurgitation of at least moderate degree was present in 14%. Neoaortic root dilation was a significant risk factor for neoaortic valve regurgitation (p < 0.0001). No patient required reintervention on the neoaorta or neoaortic valve during follow-up.

CONCLUSIONS

Progressive neoaortic root dilation is common in patients with TGA after the ASO. Continued surveillance of this population is required.

Past, present, and future of the arterial switch operation: historical review

The arterial switch operation is the extant surgical correction after a long series of palliations attempted and/or successfully achieved for the treatment of discordant ventriculoarterial connections. As early as 1954, pioneers such as Mustard, Bailey, Kay, and Idriss led the way with at first disheartening failures, temporarily leading to abandoning the procedure. The first successful atrial baffle procedure in 1958 established itself as the procedure of choice for treating discordant ventriculoarterial connections, but tenacity, courage, and vision to pursue anatomic correction finally led to the first successful arterial switch in 1975 by Jatene. After a decade to perfect surgical technique and timing indications for the various anatomic subtypes, the new era of the neonatal arterial switch since the late 1980s set the very high standards that we all know and expect today. Despite excellent early and long-term survival, important residual lesions are increasingly being recognised. Expected anatomic residuals include supravalvar pulmonary stenosis, neoaortic valve insufficiency, and coronary ostial stenosis. Reinterventions and rare, but challenging surgical reoperations address these residual findings with satisfactory outcomes. Quality of life into young adulthood is satisfactory, but functional problems include reduced exercise capacity, diffuse coronary insufficiency, and neurodevelopmental shortcomings, of which the true incidence and potential clinical implications are still unknown. The arterial switch is a spectacular anatomic correction for a once lethal condition and currently the best surgical solution for patients with discordant ventriculoarterial connections. It is, however, far from a true cure; closer and ongoing follow-up for future care will continue to be required.

National database study of survival of pediatric congenital heart disease patients in Taiwan

BACKGROUND/PURPOSE

The incidence of congenital heart disease (CHD) and severe CHD is 13.08 and 1.51/1000 live births, respectively, in Taiwan, which has had national health insurance since 1995 and child health indices similar to those in the US. This study sought to further elucidate the fatality of CHD patients and their survival from a national database.

METHODS

From the national health insurance database 2000-2010, we retrieved data from CHD patients who were diagnosed at age <6 years. The survival status at discharge was ascertained for estimation of survival.

RESULTS

In total, 18,843 pediatric CHD patients were identified. The overall prevalence of CHD was 1288 per 100 000 live-births. Severe CHD (tetralogy of Fallot (4.4%), transposition of the great arteries (1.6%) and double outlet right ventricle (1.1%)) accounted for 11.5% of all cases. The 1-month/5-year survival in simple and severe CHD was 99.1%/97.5% and 90.2%/76.4%, respectively (p < 0.0001). The Kaplan-Meier survival at 5 years of age was lowest for hypoplastic left heart syndrome (19.7%), followed by transposition of the great arteries (66.7%), double outlet right ventricle (69.0%), and common ventricle (66.0%). The 5-year survival of the birth cohort in the same study period was 99.3%.

CONCLUSION

This national database study revealed that the survival of children with simple CHD was still slightly lower than that of the general population and the survival of severe CHD patients, though only accounting for one-tenth of CHD cases, remained unsatisfactory. Such survival profiles are similar to those from Western reports and warrant a refined and dedicated medical care program for children with CHD.

Changing expectations for neurological outcomes after the neonatal arterial switch operation

BACKGROUND

Expectations for outcomes after the neonatal arterial switch operation (ASO) continue to change. This cohort study describes neurodevelopmental outcomes at age 12 months after neonatal ASO, and analyzes both modifiable and nonmodifiable factors for association with adverse outcomes.

METHODS

Patients who underwent an ASO (n=30) were enrolled in a prospective outcome study, with comprehensive clinical data collection during the first 12 months of life. Brain magnetic resonance imaging was done preoperatively and 7 days postoperatively, and the Bayley Scales of Infant Development III was performed at age 12 months.

RESULTS

Ten of 30 patients (33%) had preoperative magnetic resonance imaging injury; 13 of 30 patients (43%) had new postoperative magnetic resonance imaging injury. Twenty patients (67%) had Bayley Scales of Infant Development III: Cognitive Composite standard score mean was 104.8±15.0, Language Composite standard score median was 90.0 (25th to 75th percentile, 83 to 94), and Motor Composite standard score mean was 92.3±14.2. Best subsets multivariable analysis found associations between lower preoperative and intraoperative cerebral oxygen saturation, preoperative magnetic resonance imaging brain injury, total bypass time, and total midazolam dose and lower Bayley Scales of Infant Development III scores at age 12 months.

CONCLUSIONS

At 12 months after ASO, neurodevelopmental outcome means were within normal population ranges. The new associations reported in this study between potentially modifiable perioperative factors and outcomes require investigations in larger patient cohorts. Beyond survival, which was 100% in this cohort, factors influencing quality of life including neurodevelopmental outcomes should be routinely investigated in studies of ASO patients.

Pulmonary artery reconstruction with aorta during the arterial switch operation

Pulmonary artery (PA) reconstruction during the arterial switch operation is associated with a risk of subsequent stenosis. We present the case of a neonate who underwent an arterial switch operation and successful PA reconstruction with fresh, autologous aortic tissue. Short-term follow up has demonstrated PA growth and remodeling.