Outcomes of the Arterial Switch Operation for Transposition of the Great Arteries: 25 Years of Experience

Technical Performance Score's Association With Arterial Switch Operation Outcomes

BACKGROUND

Outcomes after the arterial switch operation (ASO) for dextro-transposition of the great arteries have improved significantly since its inception in the 1980s. This study reviews contemporaneous outcomes and predictors for late reinterventions after ASO.

METHODS

We retrospectively reviewed patients who underwent ASO for dextro-transposition of the great arteries from 1997 to 2017. Technical performance score (TPS) class (class 1, trivial or no residua; class 2, minor residua; class 3, major residua or reintervention) was assigned at discharge based on echocardiographic evaluation of components of the ASO. Multivariable Cox regression identified patient- and procedure-specific factors associated with postdischarge reinterventions.

RESULTS

Among 598 patients, 410 (69%) underwent ASO and 188 (31%) underwent ASO with ventricular septal defect repair. Median age at surgery was 5 days (interquartile range, 3 to 7); median follow-up time was 8.2 years; 408 (68%) were male; 50 (8.3%) were premature; and 10 (1.7%) had noncardiac anomalies or syndromes. Survival to hospital discharge was 98% (n = 591). Among 349 patients with follow-up, freedom from unplanned reintervent2ion at 5 years was 99% for TPS class 1, compared with 84% for class 2 and 30% for class 3. On multivariable Cox regression, classes 2 and 3 had significantly higher hazard for reintervention (class 2 hazard ratio 10.6; 95% confidence interval, 2.5 to 44.2; P = .001; class 3 hazard ratio 58.2, 95% confidence interval, 13.1 to 259; P < .001).

CONCLUSIONS

At our center, ASO was associated with relatively low mortality. Class 2 and class 3 TPS were the most important independent predictors of reinterventions after discharge. Therefore, TPS can serve as a tool for identifying high-risk patients who warrant closer follow-up.

Twenty-Three-Year Experience With the Arterial Switch Operation: Expectations and Long-Term Outcomes

We aimed to describe the short- and long-term outcomes of patients after an arterial switch operation (ASO) at a single institution during a 23-year period. A retrospective chart review of all patients <18 months of age who underwent an ASO between January 1995 and March 2018 at Texas Children's Hospital, Houston, TX was performed. Primary endpoints include mortality and reintervention. Perioperative mortality was defined as mortality occurring in-hospital and/or <30 days after surgery. Survival and freedom-from-reintervention were analyzed using Kaplan-Meier method, log-rank tests, and Cox regression models. The cohort included 394 patients. Diagnoses included 204 patients (52%) with intact ventricular septum, 137 (35%) with a ventricular septal defect, 17 (4%) with a ventricular septal defect and left ventricular outflow tract obstruction (LVOTO), and 36 (9%) with Taussig-Bing anomaly. Median age at surgery was 8 days (range: 1 day to 17 months) and median weight was 3.4 (range: 0.8-12.0) kg. Overall perioperative mortality was 1.3% (n = 5), 0.3% (n = 1) since 1999. Overall survival at 5, 10, and 15 years was 98.2%, 97.8%, and 97.8%, respectively. Perioperative morality was associated with prematurity (P = 0.012), <2.5 kg (P< 0.001), and longer circulatory arrest (P = 0.024) after univariate analysis. Reintervention was associated with a longer cross-clamp time (P < 0.001), <2.5 kg (P = 0.009), LVOTO resection (P = 0.047), and genetic syndrome (P= 0.011) after multivariable analysis. Current ASO expectations should include a perioperative mortality risk of <1% and good long-term survival. Reinterventions are more frequent in patients <2.5 kg, concomitant LVOTO resection, a genetic syndrome, and longer cross-clamp time.

Long-term quality of life in adults following truncus arteriosus repair

OBJECTIVES

To date, few studies have assessed the quality of life following congenital cardiac surgery. In this study, we aimed at determining the quality of life after truncus arteriosus (TA) repair using the Short Form 36 questionnaire in adult survivors.

METHODS

Seventy-three patients (age >18 years) who underwent TA repair at the Royal Children's Hospital, Australia were identified for the study. Of these, 42 patients (58%, 42/73) participated in the study and completed the Short Form 36 questionnaire. The results of the 8 domains and the derived health state summary score (Short Form Six Dimension, SF-6D) were compared with age-matched Australian population controls, and with patients who underwent the arterial switch operation (ASO).

RESULTS

Compared with the age-matched Australian population, 18- to 24-year-old TA patients (31%, 13/42) had lower scores in 6 of 8 domains; 25- to 34-year-old TA patients (36%, 15/42) scored lower in 5 of 8 domains; and 35- to 44-year-old TA patients (33%, 14/42) scored lower in 4 of 8 domains. SF-6D scores were not significantly different between TA patients and the age-matched Australian population. Compared with patients who underwent ASO, 18-to 24-year-old TA patients scored lower in 3 of 8 domains; and 25- to 34-year-old TA patients scored lower in 2 of 8 domains. There was no significant difference in SF-6D scores between TA and patients who underwent the ASO.

CONCLUSIONS

Adult survivors of TA have similar quality of life compared with age-matched Australian controls measured by SF-6D. Despite a higher reoperation rate in TA patients, they have similar quality of life compared with ASO patients.

Transposition of the great arteries: Fetal pulmonary valve growth and postoperative neo-aortic root dilatation

Objectives

Documentation of semilunar valve growth in fetal transposition of the great arteries (TGA) and the relationship between neo‐aortic root (NAoR) dilatation, a cause for postoperative reinterventions after the arterial switch operation (ASO), and pulmonary valve (PV) annulus dimensions prenatally.

Methods

This retrospective multicenter observational study included TGA fetuses suitable for ASO. Semilunar valve annuli pre‐ASO and NAoR diameters (post‐ASO) were measured. Trends in annulus diameters were analyzed using a linear mixed‐effects model and compared with normal values. Prenatal semilunar valve Z‐scores were correlated with NAoR diameters post‐ASO.

Results

We included 137 TGA fetuses (35.8% with significant ventricular septal defects [VSDs]). One hundred twenty‐one underwent ASO. Fetal TGA‐PV diameters were significantly larger than control aortic valve (AoV) and PV annuli from 23 and 27 weeks, respectively, especially when a VSD was present. Fetal TGA‐AoV annuli were significantly larger than control AoV and PV annuli from 26 and 30 weeks, respectively.

Z‐scores of fetal TGA‐PV and NAoR diameter at last follow‐up correlated significantly (P < .001 at 26‐30 wk).

Conclusion

Fetal TGA semilunar valve annuli are larger than control annuli, especially when there is a significant VSD. Factors besides postoperative hemodynamics, including fetal anatomy, PV Z‐score, prenatal flow, connective tissue properties, and genetics, may influence the risk for late reintervention in these fetuses.

Association Between Variation in Preoperative Care Before Arterial Switch Operation and Outcomes in Patients With Transposition of the Great Arteries

BACKGROUND

The arterial switch operation (ASO) is the gold standard operative correction of neonates with transposition of the great arteries and intact ventricular septum, with excellent operative survival. The associations between patient and surgeon characteristics and outcomes are well understood, but the associations between variation in preoperative care and outcomes are less well studied.

METHODS

A multicenter retrospective cohort study of infants undergoing neonatal ASO between January 2010 and September 2015 at hospitals contributing data to the Pediatric Health Information Systems database was performed. The association between preoperative care (timing of ASO, preoperative use of balloon atrial septostomy, prostaglandin infusion, mechanical ventilation, and vasoactive agents) and operative outcomes (mortality, length of stay, and cost) was studied with multivariable mixed-effects models.

RESULTS

Over the study period, 2159 neonates at 40 hospitals were evaluated. Perioperative mortality was 2.8%. Between hospitals, the use of adjuvant therapies and timing of ASO varied broadly. At the subject level, older age at ASO was associated with higher mortality risk (age >6 days: odds ratio, 1.90; 95% CI, 1.11-3.26; P=0.02), cost, and length of stay. Receipt of a balloon atrial septostomy was associated with lower mortality risk (odds ratio, 0.32; 95% CI, 0.17-0.59; P<0.001), cost, and length of stay. Later hospital median age at ASO was associated with higher odds of mortality (odds ratio, 1.15 per day; 95% CI, 1.02-1.29; P=0.03), longer length of stay ( P<0.004), and higher cost ( P<0.001). Other hospital factors were not independently associated with the outcomes of interest.

CONCLUSIONS

There was significant variation in preoperative care between hospitals. Some potentially modifiable aspects of perioperative care (timing of ASO and septostomy) were significantly associated with mortality, length of stay, and cost. Further research on the perioperative care of neonates is necessary to determine whether modifying practice on the basis of the observed associations translates into improved outcomes.

Arterial switch operation for transposition of the great arteries: A single-centre 32-year experience

OBJECTIVE

Arterial switch operation (ASO) is nowadays the standard of care for neonates with D-transposition of the great arteries (D-TGA). We evaluated our early and late results with ASO for D-TGA.

MATERIALS AND METHODS

We collected data on 267 patients with D-TGA, either with intact ventricular septum (D-TGA/IVS; n = 182, 68%) and with other associated congenital heart malformations (complex D-TGA; n = 85, 32%) that underwent ASO between January 1987 and July 2018.

RESULTS

Median age at ASO was 8 days (interquartile range [IQR], 6-12 days). Fifteen patients (5.6%) died in hospital (6/182 with D-TGA/IVS, 3.3% and 9/85 with complex D-TGA, 11%; P = 0.02). Median follow-up time was 10.2 years (IQR, 3.7-18 years). There were 2 (0.8%) late sudden deaths. Overall survival at 10 and 20 years was 94% and 93%, respectively. Thirty-five patients (14%) required either reoperations or reinterventions, mainly for right ventricular outflow tract obstruction (n = 28, 11%). Freedom from reoperation/reintervention at 10 and 20 years was 87% and 78%, respectively. All patients were in NYHA I at latest clinical examination. Six over 173 patients (3.4%) who underwent a postoperative evaluation of their coronaries presented acquired anomalies. Forty-four patients (17%) who performed a cardiopulmonary exercise testing (CPET) have a predicted VO ₂ comparable to normal peers.

CONCLUSIONS

The results of ASO for D-TGA are excellent, with a fairly low mortality and reoperation/reintervention rate. Functional capacity evaluated with CPET is comparable to normal peers. Continuous follow-up for detecting asymptomatic acquired coronary artery disease is mandatory. A reassessment of competitive sport eligibility criteria for specific D-TGA patients should be considered.

Pregnancy Outcomes in Women After the Arterial Switch Operation

BACKGROUND

Pregnancy outcomes after the arterial switch operation (ASO) are rare. We sought to determine outcomes of ASO survivors who underwent pregnancy.

METHODS

Female patients who had an ASO and underwent pregnancy were identified from the congenital heart disease pregnancy clinic at The Royal Melbourne Hospital. All follow-up data were collected retrospectively by medical record review.

RESULTS

Eleven (11) women were identified as having undergone medical care during pregnancy, from the adult congenital database, at The Royal Melbourne Hospital. There were 17 successful pregnancies, and nine women have been followed post pregnancy. Of the 17 successful deliveries, eight were delivered by Caesarean section, seven were vaginal deliveries and two were instrumented vaginal deliveries. Of the eight Caesarean sections, five were emergency and three were elective. The indications for emergency Caesarean section were obstructed labour (n = 2), abnormal cardiotocography (n = 1), obstructed labour and abnormal cardiotocography (n = 1) and congestive cardiac failure (n = 1). There was one neonatal complication (respiratory distress requiring intubation) in a child born at 31 weeks. There were maternal obstetric complications in 10 patients. There were two maternal cardiac complications during pregnancy (heart failure and rapid atrial fibrillation/flutter). There was no change in left ventricular function post-pregnancy. There was progression of severity of neo-aortic valve regurgitation in two patients post pregnancy (trivial to mild and moderate-severe to severe respectively).

CONCLUSION

Pregnancy post ASO appears to be safe in the majority of women. Maternal cardiac complications are uncommon in patients without residual significant haemodynamic lesions, although maternal obstetric complications may be common.

Trends in Long-Term Mortality After Congenital Heart Surgery

BACKGROUND

Congenital heart surgery has improved the survival of patients with even the most complex defects, but the long-term survival after these procedures has not been fully described.

OBJECTIVES

The purpose of this study was to evaluate the long-term survival of patients (age <21 years) who were operated on for congenital heart defects (CHDs).

METHODS

This study used the Pediatric Cardiac Care Consortium data, a U.S.-based, multicenter registry of pediatric cardiac surgery. Survival analysis included 35,998 patients who survived their first congenital heart surgery at <21 years of age and had adequate identifiers for linkage with the National Death Index through 2014. Survival was compared to that in the general population using standardized mortality ratios (SMRs).

RESULTS

After a median follow-up of 18 years (645,806 person-years), 3,191 deaths occurred with an overall SMR of 8.3 (95% confidence interval [CI]: 8.0 to 8.7). The 15-year SMR decreased from 12.7 (95% CI: 11.9 to 13.6) in the early era (1982 to 1992) to 10.0 (95% CI: 9.3 to 10.8) in the late era (1998 to 2003). The SMR remained elevated even for mild forms of CHD such as patent ductus arteriosus (SMR 4.5) and atrial septal defects (SMR 4.9). The largest decreases in SMR occurred for patients with transposition of great arteries (early: 11.0 vs. late: 3.8; p < 0.05), complete atrioventricular canal (31.3 vs. 15.3; p < 0.05), and single ventricle (53.7 vs. 31.3; p < 0.05).

CONCLUSIONS

In this large U.S. cohort, long-term mortality after congenital heart surgery was elevated across all forms of CHD. Survival has improved over time, particularly for severe defects with significant changes in their management strategy, but still lags behind the general population.

Surgical Age and Morbidity After Arterial Switch for Transposition of the Great Arteries

BACKGROUND

Transposition of the great arteries (TGA) is a complex congenital heart disease that requires early diagnosis as well as advanced surgical repair and postoperative support. This study sought to investigate the impact of surgical timing on early postoperative morbidity.

METHODS

This study reviewed all patients with TGA repaired at a single institution (Skåne University Hospital, Lund, Sweden) by arterial switch operation (ASO) between June 2001 and June 2017. Major postoperative morbidity (MPM) and death within 30 days after ASOs were documented. Patients with double-outlet right ventricle, chromosomal abnormalities, and noncardiac diseases were excluded. MPM was defined as the presence of at least 1 of the following: delayed sternum closure, reoperation, prolonged mechanical ventilation, noninvasive ventilation after extubation, peritoneal dialysis, extracorporeal membrane oxygenation, and readmission.

RESULTS

A total of 241 patients were included, with medians for birth weight, gestational week, and age at surgery of 3.5 kg, 39 weeks, and 5 days, respectively. MPM was encountered in 32.3% of patients. Prematurity (P = .001) and need for aortic arch repair at the time of ASO (P = .04) were associated with a significant increase in MPM. Non-A coronary anatomy, associated ventricular septal defect requiring surgical closure, and fetal diagnosis of TGA had no significant impact on MPM (P = .35, .08, and .21, respectively). There was no significant difference in MPM among the surgical groups (P = .49).

CONCLUSIONS

Early complications after ASO do occur and are mostly associated with prematurity and the need for aortic arch repair. Timing of surgical repair does not seem to influence the rate of these complications.

Does Coronary Reimplantation After Neoaortic Reconstruction Increase Aortic Regurgitation?

Coronary reimplantation after neoaortic reconstruction (CRANR) in the arterial switch operation (ASO) allows easy selection of accurate coronary transfer sites in the distended neoaorta. However, neoaortic valve injury may occur during coronary reimplantation. We determined whether the CRANR procedure increased the incidence of aortic valve regurgitation (AR) after ASO. Between March 1994 and August 2017, 227 patients underwent ASO. Since September 2000 CRANR has been performed on 155 patients and open coronary reimplantation (OCR) on 72. Patients who had undergone aortocoronary flaps procedures (n = 13), had early or late mortality (n = 27), or lacked data (n = 11) were excluded. We enrolled and retrospectively reviewed the medical records of 176 patients who were followed up for postoperative AR: 38 underwent OCR and 138 underwent CRANR. We compared the incidences of early and late postoperative AR in both groups. We defined mild or greater AR as "significant AR." The groups did not differ in body weight at operation, great artery relationship, and coronary artery anatomy. The incidences of significant AR at discharge were 21.1% (8/38) in the OCR group and 16.6% (23/138) in the CRANR group (p = 0.53). The freedom from significant AR at 5 years was 59.9% in the OCR group and 62.4% in the CRANR group with no difference between the two groups (p = 0.73). Moderate AR occurred in one patient in the CRANR group. No surgical intervention was required for the aortic valve in either group. ASO using the CRANR technique did not increase the incidence of postoperative early and late AR.

The great debate series: surgical treatment of aortic valve abnormalities in children

This article is the latest in an EJCTS series entitled 'The Great Debates'. We have chosen the topic of aortic valve (AoV) surgery in children, with a focus on infants and neonates. The topic was selected due to the significant challenges that AoV problems in the young may present to the surgical team. There are many areas of active controversy, despite the vast accumulated world experience. We have tried to incorporate many of these issues in the questions posed, not claiming to be all-inclusive. The individuals invited to this debate are experts in paediatric valve surgery, with broad and successful clinical experiences on multiple continents. We hope that the facts and opinions presented in this debate will generate interest and discussion and perhaps prove useful in decision-making for future complex valve cases.

The Relationship Between Pre-operative Left Ventricular Longitudinal Strain and Post-operative Length of Stay in Patients Undergoing Arterial Switch Operation Is Age Dependent

INTRODUCTION

Post-operative length of stay (LOS) after the arterial switch operation (ASO) is variable. The association between pre-operative non-invasive measures of ventricular function and post-operative course has not been well established. The aims of this study were to (1) evaluate the relationship between pre-operative non-invasive measures of ventricular function and post-operative LOS and (2) evaluate the change in ventricular function after ASO.

METHODS

Data were reviewed in consecutive ASO patients between 2010 and 2016. The primary outcome was post-operative LOS. Echocardiograms obtained during the pre-operative period and at the time of discharge were retrospectively analyzed using speckle-tracking echocardiography. Pearson's correlation between patient-specific, pre-operative, and echocardiographic data versus post-operative LOS was assessed.

RESULTS

Fifty-two patients were included in analyses, 39 neonates and 13 infants. Left ventricular (LV) longitudinal strain correlated with post-operative LOS for infants age > 28 days (r = 0.62, p = 0.03), but not for neonates (r = 0.14, p = 0.40). Operative age (r = - 0.42, p = 0.003), weight at surgery (r = - 0.48, p ≤ 0.001), and cardiopulmonary bypass time (r = 0.30, p = 0.045) also correlated with post-operative LOS. Standard 2D measures of ventricular function did not correlate with post-operative LOS. LV ejection fraction and longitudinal strain worsened post-operatively.

CONCLUSION

Higher pre-operative LV longitudinal strain (representing worse LV function) is associated with increased post-operative LOS after ASO in infants > 28 days, but not in neonates. LV ejection fraction and longitudinal strain worsened after ASO. Future studies should assess the utility of performing STE in risk stratifying patients prior to ASO.

Aortic Root Reimplantation in a Patient Who Underwent an Arterial Switch Operation

Neo-aortic insufficiency associated with root enlargement following an arterial switch operation is a serious late complication. To achieve successful surgical correction of this condition, multiple factors should be considered, including the individual patient’s anatomy, the challenging nature of the redo procedure, and the patient’s young age. However, limited publications have described the use of valve-sparing techniques for the treatment of neo-aortic insufficiency associated with root enlargement following an arterial switch operation. Herein, we report our recent experience of a valve-sparing aortic root procedure with ascending aorta and hemiarch replacement despite the presence of a discrepancy in leaflet size and nearby severe adhesions.

Interpretation and Reporting of Coronary Arteries in Transposition of the Great Arteries: Cross-sectional Imaging Perspective

Knowledge of coronary artery nomenclature in transposition of the great arteries is essential, given the increasing population of adults with congenital heart disease and greater utilization of imaging in these patients. This article reviews appropriate terminology for describing coronary artery anatomy, commonly encountered coronary artery patterns, and postoperative coronary complications in the setting of transposition of the great arteries.

Utility of Follow-Up Annual Echocardiograms in Patients With Complete Transposition of the Great Arteries After Arterial Switch Operations

The arterial switch operation (ASO) in complete transposition of the great arteries (TGA) has increased long-term survival. Annual follow-up echocardiograms are recommended, but evidence-based guidelines do not exist. We sought to assess how often a patient with TGA after ASO who had no symptoms or change in physical exam underwent an intervention based solely on echocardiographic changes. We retrospectively reviewed all records from patients with TGA and a history of ASO followed at our institution between November 1983 and January 2015. Changes in echocardiograms resulting in hospital admission, significant medication change, interventional catheterization, or surgical procedure were identified through the surgical and cardiac catheterization laboratory databases and patient charts. These changes were referred to as an actionable change (AC). Interventions were defined as being driven by either clinical (change in physical exam, patient and/or parental concerns) or echocardiographic findings. A total of 1,792 echocardiograms from 149 patients were reviewed. Median number of echocardiograms per patient was 12 (1 to 34). Of the 1,792 echocardiograms, 20 (1.12%) were associated with AC. The most common intervention for an AC was cardiac catheterization (13 of 20, 65%). Most AC (15 of 20, 75%) occurred in the first decade after ASO. AC occurred in 83% (5 of 6) of those with a history of both ASO and arch repair. Annual echocardiograms in patients with TGA after ASO are rarely useful and are unnecessary. In conclusion, decreasing surveillance of asymptomatic patients to biennial follow-up echocardiograms in asymptomatic patients without physical examination changes is safe and would decrease medical expenses.

Long-term Outcomes of the Arterial Switch Operation for d-Transposition of the Great Arteries

Dextrotransposition of the great arteries (d-TGA) is a relatively rare form of complex childhood congenital heart disease, which occurs in approximately 0.2 in 1000 live births (Long et al, 2010). The most common palliative procedure for this anatomy has become the arterial switch operation (ASO). We will review in this paper the evidence that is currently available regarding the clinical management following the ASO. Individuals with d-TGA who undergo ASO at a young age thus far have excellent long-term outcomes. Long-term complications for the ASO should be monitored for and patients should have routine follow-up with specialists in adult congenital heart disease.

Long-Term Survival After Arterial Versus Atrial Switch in d-Transposition of the Great Arteries

BACKGROUND

The arterial switch operation (ASO) became the procedure of choice for dextro-transposition of the great arteries (d-TGA) nearly 30 years ago, but the long-term results of this operation are unknown. We aimed to compare the long-term transplant-free survival of patients with d-TGA who underwent ASO versus atrial switch in the Pediatric Cardiac Care Consortium.

METHODS

We performed a retrospective cohort study of d-TGA patients undergoing ASO or atrial switch in the United States between 1982 and 1991. Long-term transplant-free survival was obtained by linking Pediatric Cardiac Care Consortium data with the National Death Index and the Organ Procurement and Transplant Network. Kaplan-Meier survival plots were constructed, and multivariable regression was used to compare long-term transplant-free survival.

RESULTS

Of 554 d-TGA patients who underwent ASO (n = 259) or atrial switch (n = 295), the 20-year overall transplant-free survival was 82.1% for those undergoing ASO and 76.3% for those who had atrial switch procedure. Adjusted overall transplant-free survival beyond 10 years after operation was superior for ASO compared with atrial switch (hazard ratio 0.07, 95% confidence interval: 0.01 to 0.52, p = 0.009). During this period, the ASO had higher in-hospital mortality than the atrial switch (21.6% versus 12.9%, p = 0.007). After excluding patients with in-hospital mortality, the transplant-free survival 20 years after repair was 97.7% for the ASO patients versus 86.3% for the atrial switch patients.

CONCLUSIONS

Despite initial higher in-hospital mortality for ASO during the study period, there is a significant long-term transplant-free survival advantage for ASO as compared with atrial switch for d-TGA surgery. Ongoing monitoring is required to assess late risk of cardiovascular disease.

Risk factor analysis for a complicated postoperative course after neonatal arterial switch operation: The role of troponin T

OBJECTIVE

To find risk factors for a complicated early postoperative course after arterial switch operation (ASO) in neonates with d-transposition of the great arteries (dTGA). In addition to anatomical and surgical parameters, the predictive value of early postoperative troponin T (TnT) values in correlation to the early postoperative course after ASO is analyzed.

METHODS

Seventy-nine neonates (57 (72%) male) with simple dTGA treated by ASO between 2009 and 2016 were included in the analysis. A complicated early postoperative course (30 days) was defined by one of the following criteria: (A) moderate to severe cardiac dysfunction without rhythm disturbances, (B) rhythm disturbances causing hemodynamic instability with the need for medical treatment, (C) signs for ischemia in ECG, (D) need for surgical or catheter interventional reinterventions other than diagnostic, or (E) other reasons.

RESULTS

Forty of 79 patients (51%) showed a complicated early postoperative course after ASO, with 2 patients dying after 13 and 16 days. Patients with a complicated early postoperative course had a longer PICU stay (P < .001), needed longer mechanical ventilator support (P = .001) and longer inotropic support (P = .03), and more reinterventions (surgical or catheter interventional) were necessary (P = .001). Only the presence of a VSD (P = .001) and longer surgery duration (P = .026) were associated to a complicated postoperative course. TnT values only showed a trend toward higher values in patients with a complicated postoperative course (P = .06). A secondary rise in TnT was seen in 10 patients, ranging from 11.6% to 410.2%, of whom 7 could be classified in the complicated postoperative group.

CONCLUSIONS

The postoperative course after ASO in dTGA neonates is influenced by other cardiac comorbidities like a VSD with the need for surgical treatment, influencing surgery duration. Postoperative higher TnT values reflect a longer and more vulnerable intraoperative course with limited predictive value on the early postoperative course.

Left ventricular function and exercise capacity after arterial switch operation for transposition of the great arteries: a systematic review and meta-analysis

BACKGROUND

The arterial switch operation for transposition of the great arteries was initially believed to be an anatomical correction. Recent evidence shows reduced exercise capacity and left ventricular function in varying degrees in the long term after an arterial switch operation.

OBJECTIVE

To perform a meta-analysis on long-term exercise capacity and left ventricular ejection fraction after an arterial switch operation.

METHODS

A literature search was performed to cover all studies on patients who had undergone a minimum of 6 years of follow-up that reported either left ventricular ejection fraction, peak oxygen uptake, peak workload, and/or peak heart rate. A meta-analysis was performed if more than three studies reported the outcome of interest.

RESULTS

A total of 21 studies reported on the outcomes of interest. Oxygen uptake was consistently lower in patients who had undergone an arterial switch operation compared with healthy controls, with a pooled average peak oxygen uptake of 87.5±2.9% of predicted. The peak heart rate was also lower compared with that of controls, at 92±2% of predicted. Peak workload was significantly reduced in two studies. Pooled left ventricular ejection fraction was normal at 60.7±7.2%.

CONCLUSION

Exercise capacity is reduced and left ventricular ejection fraction is preserved in the long term after an arterial switch operation for transposition of the great arteries.

Long-term Management of the Arterial Switch Patient

PURPOSE OF REVIEW

This review paper describes the management of patients with dextro-transposition of the great arteries (D-TGA) with a focus on the complications seen and the appropriate care required to identify and prevent adverse events.

RECENT FINDINGS

D-TGA is a form of cyanotic congenital heart disease (CHD) representing ~ 3% of all CHD and almost 20% of all cyanotic CHD. Since the late 1980s, standard of care is to repair these patients with an arterial switch operation (ASO) as opposed to a Mustard/Senning operation. The long-term survival and complication rates are superior in the ASO. Long-term follow-up is recommended for all D-TGA patients and includes management with adult congenital heart disease specialists and the use of echocardiography and advanced imaging with CT or MRI. The most common complications seen are pulmonary stenosis, coronary artery stenosis, and neo-aortic regurgitation. Careful evaluation of new symptoms or declining function is essential in preventing and treating these long-term sequelae.

Pediatric Coronary Artery Bypass Surgery for Congenital Heart Disease

BACKGROUND

Pediatric coronary artery bypass surgery (PCABS) for congenital heart disease has become increasingly important in infants and children undergoing modern cardiac surgical procedures, because of its life-saving potential in unsuccessful coronary transfer operation. This review summarizes the current surgical role of PCABS for treating congenital heart diseases.

METHODS

Databases, mainly PubMed, were searched for relevant publications about coronary bypass operation in the pediatric population, from 1970 (commencement) to March 2018.

RESULTS

The five main indications were (1) anomalous origin of the left coronary artery from the pulmonary artery, (2) left main coronary trunk atresia, (3) acute and late coronary events in the arterial switch operation for transposition of the great arteries, (4) the Ross operation for congenital aortic stenosis complicated by destructive infective endocarditis, and (5) inadvertent coronary artery injury during heart operation. Direct coronary reimplantation (coronary transfer) in most and surgical angioplastic procedures in selected patients were the first choice; however, PCABS with internal thoracic artery (ITA) grafts can be lifesaving in emergency or severe myocardial hypoperfusion conditions. Because the patency of saphenous vein grafts is poorer than that of ITA grafts, their use should be avoided in growing children. The procedure can be performed safely in neonates, infants, and small children, using high-power magnifying glasses or a surgical microscope.

CONCLUSIONS

Long-term results of survival and ITA graft function are excellent in growing children and adults. Congenital heart surgeons should be trained in quick graft takedown and in coping with emergency and late devastating complications in coronary transfer operation.

Population trends in prenatal detection of transposition of great arteries: impact of obstetric screening ultrasound guidelines

OBJECTIVES

Dextro-transposition of the great arteries (d-TGA) is one of the most common critical neonatal heart defects, with a low detection rate antenatally. We sought to evaluate trends in the prenatal detection of d-TGA with or without ventricular septal defect (VSD) in Alberta over the past 13 years, examining the potential impact of ultrasound guidelines incorporating screening of cardiac outflow tracts, updated in 2009-2010 and in 2013, and factors affecting detection of the condition.

METHODS

All fetuses and neonates with d-TGA, with or without VSD, encountered between 2003 and 2015 in the province of Alberta, were identified retrospectively. Clinical records including obstetric ultrasound reports were reviewed. Pregnancy outcome, common referral indications and associated maternal and fetal pathology in affected pregnancies were assessed.

RESULTS

From 2003 to 2015, 127 cases with d-TGA were encountered in Alberta, of which 47 (37%) were detected prenatally. Prenatal detection improved over the study period, from 14% in 2003-2010, to 50% in 2011-2013, and to 77% in 2014-2015. Of the 47 fetuses with a prenatal diagnosis of d-TGA, an indication for fetal echocardiography included abnormal or poorly visualized cardiac outflows with normal four-chamber view in 46 (98%). Comorbidities were identified in 12 mothers, only five of which represented an additional reason for fetal echocardiography referral, and four fetuses had extracardiac pathology.

CONCLUSION

Substantial improvement in the prenatal detection of d-TGA has been observed in Alberta over the past few years, owing to improved screening of cardiac outflow tracts on routine obstetric ultrasound examination in otherwise healthy pregnancies, and has been temporally associated with updated obstetric ultrasound guidelines suggesting that these contributed to optimized screening of affected pregnancies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Aortopulmonary collaterals in neonates with d-transposition of the great arteries - Clinical significance early after arterial switch operation

OBJECTIVES

Purpose of this study is to evaluate the clinical significance of major aortopulmonary collateral arteries (MAPCAs) during the early postoperative course after arterial switch operation (ASO) in d-transposition of the great arteries (dTGA).

METHODS

Clinical data of 98 patients with simple dTGA between January 2007 and December 2016 at the University Children's Hospital Zurich, Switzerland were analyzed retrospectively.

RESULTS

37 from 98 patients (38%) required cardiac catheterization (CC) due to an early complicated postoperative course or difficult coronary transfer due to special coronary anatomy. In 15 (15%) patients, hemodynamically relevant MAPCAs were found during CC and coil embolization was performed. Patients with relevant MAPCAs had a significantly longer PICU stay (7 versus 6 days, p = 0.021), longer hospital stay (41 versus 27 days, p = 0.005), longer mechanical ventilation time (5 versus 3 days, p = 0.005), longer need for inotropic support (5 versus 4 days, p = 0.001) and delayed chest closure time (3 versus 2 days, p = 0.030) in those in whom it was left open in comparison to all other patients. In patients having CC, pre-surgery oxygen saturation was significantly lower in patients with relevant MAPCAs (58% vs 70%, p 0.019). Echocardiography had a sensitivity of 53% and a specificity of 100% in detecting relevant MAPCAs, accurately.

CONCLUSIONS

MAPCAs are frequently found in dTGA patients and can be associated with lower baseline oxygen saturation and a prolonged postoperative course after ASO. Transthoracic echocardiography cannot replace CC as diagnostic tool. If significant MAPCAs are suspected, early CC should be performed for diagnostic and therapeutic reasons.

Managing congenital heart disease in the obstetric patient

OBJECTIVE

Cardiovascular disease is the major cause of pregnancy-related maternal mortality in the United States, and congenital heart disease (CHD) is the most common form of structural heart disease affecting women of childbearing age. Most females born with CHD will reach childbearing age and consider pregnancy. Adult CHD and maternal-fetal medicine (MFM) specialists managing women with CHD should provide preconception counseling, cardiovascular risk assessment prior to pregnancy that estimates maternal and fetal risk, management during pregnancy, and in the peripartum period and also know the potential complications and special circumstances that may occur in the post-partum period. This chapter will review the population at risk, patient risk prior to pregnancy, management during pregnancy, management in the peripartum and post-partum periods, and outline specific cardiovascular complications. The chapter will also briefly review some common or high-risk congenital cardiovascular lesions commonly encountered.

CONCLUSION

Management of patients with most forms of CHD encountered during pregnancy requires a multidisciplinary approach and careful team-based care to facilitate safe and appropriate management and pregnancy success.

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.

Update on the Management of Adults With Arterial Switch Procedure for Transposition of the Great Arteries

OPINION STATEMENT

The arterial switch operation (ASO) is now the most frequently performed surgical correction in individuals with dextro-transposition of the great arteries (D-TGA). Patients who undergo this procedure as neonates have overall good clinical outcomes yet continued clinical follow-up is important to evaluate for postoperative complications. In this group, the highest mortality is in the immediate postoperative period and is generally associated with reimplantation of the coronary arteries. As these patients live into adulthood, longitudinal follow-up for other ASO complications including neo-pulmonary stenosis, right ventricular outflow tract (RVOT) obstruction, or neo-aortic root dilation and resulting aortic insufficiency should be performed. In adults, extra care should be taken to identify and treat traditional cardiovascular risk factors as individuals with coronary obstruction may not present with typical anginal symptoms. Management of these patients should be performed in collaboration with an adult congenital heart center of excellence. This population offers a unique opportunity to provide timely feedback to adult congenital heart community of providers regarding late outcomes from surgical intervention and in the next decade will hopefully demonstrate a model for clinical feedback cycles in lifelong congenital care.

Management of Pregnancy in Patients With Complex Congenital Heart Disease: A Scientific Statement for Healthcare Professionals From the American Heart Association

Today, most female children born with congenital heart disease will reach childbearing age. For many women with complex congenital heart disease, carrying a pregnancy carries a moderate to high risk for both the mother and her fetus. Many such women, however, do not have access to adult congenital heart disease tertiary centers with experienced reproductive programs. Therefore, it is important that all practitioners who will be managing these women have current information not only on preconception counseling and diagnostic evaluation to determine maternal and fetal risk but also on how to manage them once they are pregnant and when to refer them to a regional center with expertise in pregnancy management.

Emerging Research Directions in Adult Congenital Heart Disease: A Report From an NHLBI/ACHA Working Group

Congenital heart disease (CHD) is the most common birth defect, affecting about 0.8% of live births. Advances in recent decades have allowed >85% of children with CHD to survive to adulthood, creating a growing population of adults with CHD. Little information exists regarding survival, demographics, late outcomes, and comorbidities in this emerging group, and multiple barriers impede research in adult CHD. The National Heart, Lung, and Blood Institute and the Adult Congenital Heart Association convened a multidisciplinary working group to identify high-impact research questions in adult CHD. This report summarizes the meeting discussions in the broad areas of CHD-related heart failure, vascular disease, and multisystem complications. High-priority subtopics identified included heart failure in tetralogy of Fallot, mechanical circulatory support/transplantation, sudden cardiac death, vascular outcomes in coarctation of the aorta, late outcomes in single-ventricle disease, cognitive and psychiatric issues, and pregnancy.

In-Hospital Vital Status and Heart Transplants After Intervention for Congenital Heart Disease in the Pediatric Cardiac Care Consortium: Completeness of Ascertainment Using the National Death Index and United Network for Organ Sharing Datasets

BACKGROUND

The long-term outcomes of patients undergoing interventions for congenital heart disease (CHD) remain largely unknown. We linked the Pediatric Cardiac Care Consortium (PCCC) with the National Death Index (NDI) and the United Network for Organ Sharing Dataset (UNOS) registries to study mortality and transplant occurring up to 32 years postintervention. The objective of the current analysis was to determine the sensitivity of this linkage in identifying patients who are known to have died or undergone heart transplant.

METHODS AND RESULTS

We used direct identifiers from 59 324 subjects registered in the PCCC between 1982 and 2003 to test for completeness of case ascertainment of subjects with known vital and heart transplant status by linkage with the NDI and UNOS registries. Of the 4612 in-hospital deaths, 3873 were identified by the NDI as "true" matches for a sensitivity of 84.0% (95% CI, 82.9-85.0). There was no difference in sensitivity across 25 congenital cardiovascular conditions after adjustment for age, sex, race, presence of first name, death year, and residence at death. Of 455 known heart transplants in the PCCC, there were 408 matches in the UNOS registry, for a sensitivity of 89.7% (95% CI, 86.9-92.3). An additional 4851 deaths and 363 transplants that occurred outside the PCCC were identified through 2014.

CONCLUSIONS

The linkage of the PCCC with the NDI and UNOS national registries is feasible with a satisfactory sensitivity. This linkage provides a conservative estimate of the long-term death and heart transplant events in this cohort.

Prenatal diagnosis, hospital characteristics, and mortality in transposition of the great arteries

BACKGROUND

The role of prenatal diagnosis in reducing neonatal mortality from transposition of the great arteries (TGA) is controversial. Factors affected by prenatal diagnosis such as proximity at birth to a cardiac surgical center (CSC) and CSC volume are associated with mortality in congenital heart disease. The purpose of the study was to determine the associations between prenatal diagnosis, distance from birthplace to a CSC, CSC TGA volume, and neonatal mortality in patients with TGA.

METHODS

The Texas Birth Defects Registry was queried for all live born infants with TGA from 1999 to 2007. Four hundred sixty-eight cases of TGA were included.

RESULTS

Forty-eight patients (10.3%) were prenatally diagnosed, and 20 patients died before age 28 days (4.3%). Neither prenatal diagnosis nor close proximity to a CSC at birth (p > 0.05) were associated with decreased mortality. Low CSC TGA volume was associated with increased mortality (p < 0.0002). Mortality at the CSCs with <5 patients per year was 9.6%; CSCs with 5 to 10 patients per year had 0% mortality, and those with >10 patients per year had 2.3% mortality. In multivariable logistic regression, only preterm birth (odds ratio, 7.05; 95% confidence interval, 4.13-12.05) and lower CSC volume (p < 0.001) were associated with neonatal mortality, although prenatal diagnosis attenuated the detrimental association of lower volume CSCs with higher mortality (p for interaction = 0.047).

CONCLUSION

Lower CSC TGA patient volume was associated with higher neonatal mortality. Prenatal diagnosis may improve survival in lower volume CSCs. Birth Defects Research (Part A) 106:739-748, 2016. © 2016 Wiley Periodicals, Inc.