Long-term survival and functional follow-up in patients after the arterial switch operation

Excellent Survival With a Focus on Pulmonary Artery Reinterventions After the Arterial Switch Operation

Background: We sought to evaluate the outcomes in patients who underwent the arterial switch operation (ASO) over a 20-year period at a single institution. Methods: The current study is a retrospective review of 180 consecutive patients who underwent the ASO for biventricular surgical correction of dextro-transposition of the great arteries (d-TGA) between 2002 and 2022. Results: Among 180 patients, 121 had TGA-intact ventricular septum, 47 had TGA-ventricular septal defect and 12 had Taussig-Bing Anomaly (TBA). The median follow-up time was 6.7 years (interquartile range: 3.9-8.7 years). There were five early (2.8%) and one late (0.6%) mortality. Survival was 96.6% at one year and beyond. Reoperations were performed in 31 patients (17%). Taussig Bing Anomaly was found to increase the risk of reoperation by 17 times (P < .0001). A total of 37 (21%) patients underwent 53 reinterventions (14 surgical procedures, 39 catheter interventions) specifically addressing pulmonary artery (PA) stenosis. Freedom from PA reintervention was 97%, 87%, 70%, and 55% at 1, 5, 10, and 15 years, respectively. By bivariable analysis, TBA (P = .003, odds ratio [OR]: 6.4, 95% confidence interval [CI]: 1.9-21.7), mild PA stenosis at discharge (P ≤ .001, OR: 6.1, 95% CI: 2.7-13.6), and moderate or severe PA stenosis at discharge (P ≤ .001, OR: 12.7, 95% CI: 5-32.2) were identified as predictors of reintervention on PA. In the last follow-up of 174 survivors, 24 patients (14%) had moderate or greater PA stenosis, two (1%) had moderate neoaortic valve regurgitation, and 168 were New York Heart Association status I. Conclusions: Our results demonstrated excellent survival and functional status following the ASO for d-TGA; however, patients remain subject to frequent reinterventions especially on the pulmonary arteries.

Pulmonary, aorta, and coronary arteries post-arterial switch in transposition of great arteries: intermediate-term surveillance utilizing conventional echocardiography and cardiac multislice computed tomography

BACKGROUND

Arterial switch operation (ASO) is the standard surgical choice for D-transposition of great arteries (D-TGA). However, the implications of ASO on pulmonaries, coronaries, and aorta have not been adequately investigated. The current study evaluates arterial morphologic changes post-ASO at intermediate-term surveillance.

METHODS

From May 2021 to May 2022, patients with D-TGA who underwent ASO for more than six months were recruited. Preoperative and operative data were collected. Patients were assessed using echocardiography (ECHO) and multislice CT angiography (MSCT) to evaluate pulmonary, coronary, and aortic arterial anatomy.

RESULTS

Twenty patients were included with median age of 11 (10-23.25) days at ASO and 14 (7.25-32.75) months on last follow-up. Neo-aortic regurgitation was detected in 12(60%) and neo-pulmonary regurgitation in 3 (15%). Using ECHO, complete evaluation of pulmonary arteries (PAs) was not achieved in 35% and incomplete coronaries assessment in 40% of cases. No stenosis was detected in coronaries using MSCT, although coronary anomalies were found in 9/20 (45%). Dilated Aortic annulus was detected in 16/20 (80%), dilated aortic root in 18/20 (90%), and dilated sinotubular junction in 70%. Right PA stenosis was diagnosed in 10/20 (50%) and left PA(LPA) stenosis in 7/20 (35%). Although Z-score of PAs did not correlate with aortic data, LPA bending angle was positively correlated to neo-aortic root diameter and Z-score (rho = 0.65,p = 0.016; rho = 0.69,p = 0.01), respectively.

CONCLUSION

Echocardiography alone is not a conclusive surveillance tool for detecting late post-ASO anatomic changes in D-TGA patients. Cardiac MSCT should be considered for comprehensive evaluation on the intermediate-term follow-up post-ASO to accurately track morphologic abnormalities in the aorta, pulmonary, and coronary arteries.

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.

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.

Left bronchial compression after an arterial switch operation with the LeCompte maneuver for transposition of the great arteries: A case report and literature review

Left bronchial compression is a rarely reported, postoperative complication of the arterial switch operation with the LeCompte maneuver for transposition of the great arteries. Postoperative neopulmonary root dilatation and the anterior-posterior, anatomical relationship of the great vessels may cause this condition. Hypoxic pulmonary vasoconstriction may mask the condition even if the left bronchus has been severely obstructed. The apparent inconsistency between the abnormally decreased pulmonary blood flow and the absence of any irregularities in the vascular structure that might account for it suggested hypoxic pulmonary vasoconstriction to be the cause. We present herein a case of left bronchial compression presenting malacia after an arterial switch operation with the LeCompte maneuver and also present a review of seven, other, reported cases.

Learning objectives

Left bronchial compression is a rare complication of the arterial switch operation with the LeCompte maneuver for transposition of the great arteries and is possibly caused by root dilatation and the anatomical relationship of the great vessels. Hypoxic pulmonary vasoconstriction may mask the condition.

Factors Affecting Health-Related Quality of Life After the Arterial Switch Operation

BACKGROUND

Long-term morbidity and mortality outcomes of the arterial switch operation (ASO) in patients with transposition of the great arteries and Taussig-Bing anomaly are excellent. With an increasing number of patients reaching adolescence and adulthood, more attention is directed toward quality of life. Our study aimed to determine the health-related quality of life (hrQoL) outcomes in patients after the ASO and identify factors influencing their hrQoL.

METHODS

In this cross-sectional study, hrQoL of patients after ASO was assessed with the German version of the Short Form-36 (SF-36) and the potential association of specified clinical factors was analyzed. Patients of at least 14 years of age who underwent ASO in our institution from 1983 were considered eligible.

RESULTS

Of the 355 questionnaires sent to eligible patients, 261 (73%) were available for analysis. Compared to the reference population, patients who had undergone ASO had a significantly higher score in all subscales of the SF-36 except for vitality (P < .01). Patients with an implanted pacemaker (P = .002), patients who required at least one reoperation (P < .001), and patients currently taking cardiac medication (P < .004) or oral anticoagulation (P = .036) had lower physical component scores compared to patients without these factors.

CONCLUSIONS

Patients' self-assessed and self-reported hrQoL after ASO (using German version of the Short Form 36) is very good. In this population, hrQoL is influenced by reoperation, the need for a pacemaker, and current cardiac medication or anticoagulant use. The development of strategies designed to mitigate or minimize the requirements for, and/or impact of these factors may lead to better hrQoL in this patient population.

Echocardiography and MRI parameters associated with exercise capacity in patients after the arterial switch operation

BACKGROUND

The arterial switch operation (ASO) for transposition of the great arteries has excellent survival, but a substantial number of patients suffer from a reduced exercise capacity. The goal of this study was to identify imaging parameters associated with a reduced exercise capacity in patients after ASO.

METHODS

A retrospective analysis was performed of ASO patients who underwent cardiopulmonary exercise testing (CPET) between 2007 and 2017. Reduced exercise performance was defined as a reduced workload peak (W_peak) with Z-score <-2 or a peak oxygen uptake indexed for weight (VO_2peak/kg) with Z-score <-2. Data on echocardiography and cardiac magnetic resonance performed within 1 year of the CPET were collected for comparison.

RESULTS

A total of 81 ASO patients (age 17±7 years) were included. Reduced exercise performance was found in 22 patients (27%) as expressed by either a reduced W_peak and/or a reduced VO_2peak/kg. Main pulmonary artery gradient and tricuspid regurgitation gradient by echocardiography were found to be associated with reduced W_peak (p=0.031; p=0.020, respectively). The main pulmonary artery gradient and tricuspid regurgitation gradient by echocardiography were found to be associated with reduced VO_2peak/kg (p=0.009; p=0.019, respectively). No left ventricular parameters were found to be associated with abnormal exercise performance.

CONCLUSION

This study demonstrates that ASO patients frequently experience reduced exercise capacity. Echocardiographic evidence of main pulmonary artery stenosis and increased right ventricular pressure were associated with reduced exercise capacity, and are therefore key to monitor during serial follow-up of ASO patients.

Outcomes of arterial switch operation for Taussig-Bing anomaly versus transposition of great arteries and ventricular septal defect

Background

This study aims to present the outcomes of arterial switch operation for Taussig-Bing anomaly versus transposition of the great arteries and ventricular septal defect.

Methods

Between November 2010 and December 2016, a total of 100 consecutive arterial switch operations in 42 pediatric patients (25 males, 17 females; median age 17 days; range, 2 to 210 days) were performed in two centers. Among them, 42 patients had associated ventricular septal defect and were diagnosed with Taussig-Bing anomaly (n=15) or transposition of the great arteries and ventricular septal defect (n=27). Aortic arch anomalies were present in six patients (40%) with Taussig-Bing anomaly and two patients (7.4%) with transposition of the great arteries and ventricular septal defect (p=0.016). Coronary anomaly was observed in five (33.3%) and six (22.2%) patients, respectively. All patient had a large defect (multiple n=4), except for eight patients who had moderate defect in the transposition of the great arteries group.

Results

Early mortality was 13.3% in the Taussig-Bing anomaly group and 7.4% in the other group. Extracorporeal membrane oxygenation support was needed in three patients. Delayed sternal closure was used in most of the patients (92.9%). The median length of intensive care unit and hospital stays were similar between the groups. The median follow-up was 16 (range, 1 to 50) months. Two patients including one planned (debanding and multiple defect closure) and one unplanned (residual defect closure) were reoperated. Three patients needed aortic balloon angioplasty due to recoarctation and one patient underwent pulmonary balloon angioplasty. Overall reintervention rate was 18.4%.

Conclusion

Although the incidence of aortic arch and coronary anomalies were higher in patients with Taussig-Bing anomaly, early and mid-term results were similar. Based on these results, primary arterial switch operation seems to be successfully performed for both pathologies.

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.

Longitudinal Associations between Neurodevelopment and Psychosocial Health Status in Patients with Repaired D-Transposition of the Great Arteries

OBJECTIVE

To examine associations between measurements of neurodevelopment and psychosocial health status at age 8 and 16 years in patients with repaired dextro-transposition of the great arteries.

STUDY DESIGN

In the 16-year follow-up of the Boston Circulatory Arrest Study, 137 parents completed the Child Health Questionnaire-Parent Form-50, of whom 135 had completed the Child Health Questionnaire-Parent Form-50 when their child was age 8 years. Psychosocial and physical summary scores were used to assess change in health status from age 8 to 16 years. A comprehensive battery of neurodevelopmental testing was performed at ages 8 and 16 years to examine associations with adolescent health status.

RESULTS

Lower psychosocial summary scores of 16 year old subjects with dextro-transposition of the great arteries were highly associated with numerous concurrent domains of neurodevelopmental function, most notably with higher (worse) scores on the Conners' Attention Deficit Hyperactivity Disorder/Diagnostic and Statistical Manual-4th Edition Scales (parent: r = -0.62, P < .001; adolescent: r = -0.43, P < .001) and the Behavior Rating Inventory of Executive Function Global Executive Composite (parent: r = -0.66, P < .001; adolescent: r = -0.39, P < .001). Psychosocial and physical summary scores tracked from ages 8 to 16 years (r = 0.44 and 0.47, respectively, P < .001 for each). Higher (worse) scores of multiple attention measures at age 8 years predicted worse psychosocial summary scores at age 16 years.

CONCLUSIONS

Attention deficits at age 8 years were highly predictive of worse psychosocial health status in adolescence. Further studies are needed to assess whether treatment of childhood attention deficit hyperactivity disorder could improve adolescent well-being.

Mid- and Longterm Neo-Aortic Valve Regurgitation after Jatene Surgery: Prevalence and Risk Factors

Background

Jatene surgery became the surgical procedure of choice to repair transposition of the great arteries (TGA) in neonates and infants. Late complications, mainly related to the pulmonary outflow tract and coronary arteries, are well known. The behavior of the neo-aortic valve is a cause of concern because of its potential for requiring late reoperation.

Objectives

To assess the prevalence and risk factors of neo-aortic valve regurgitation in 127 patients in the late postoperative period of the Jatene surgery.

Methods

Of the 328 survivors of the Jatene surgery at the Biocor Institute from October 1997 to June 2015, all patients undergoing postoperative follow-up were contacted via telephone, 127 being eligible for the study. The patients were divided into two groups, simple TGA and complex TGA groups, with follow-up means of 6.4 ± 4.7 years and 9.26 ± 4.22 years, respectively. Echocardiography was performed with adjusted measurements (Z-score) of the neo-aortic annulus, sinus of Valsalva, sinotubular region and ascending aorta, as well as quantification of the neo-aortic valve regurgitation grade.

Results

The incidence of mild neo-aortic valve regurgitation was 29% in a follow-up of 7.4 ± 4.7 years. Moderate regurgitation was identified in 24 patients with age mean (± standard-deviation) of 9.81 ± 4.21 years, 19 of whom (79%) in the complex TGA group. Those patients had a higher aortic annulus Z-score. The reoperation rate due to neo-aortic regurgitation associated with aortic dilation was 1.5%, all patients in the complex TGA group.

Conclusion

This study shows that, despite the low incidence of reoperation after Jatene surgery due to neo-aorta dilation and neo-aortic valve regurgitation, that is a time-dependent phenomenon, which requires strict vigilance of the patients. In this study, one of the major risk factors for neo-aortic valve regurgitation was the preoperative pulmonary artery diameter (p < 0.001).

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.

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.

Collagen turnover biomarkers and systemic right ventricle remodeling in adults with previous atrial switch procedure for transposition of the great arteries

Background

Myocardial fibrosis is a potential pathophysiological mechanism leading to systemic right ventricular (SRV) deterioration. We hypothesize that circulating levels of collagen deposition markers are elevated in patients with SRV remodeling and this elevation may have a predictive value.

Methods

We prospectively evaluated 56 patients with D-TGA after the atrial switch procedure (mean age 25.6 ± 4.8, range 18–37 years; 67% males). Serum levels of procollagen type III amino-terminal propeptide (PIIINP), collagen type I carboxy-terminal telopeptide (CITP), procollagen type I N-terminal propeptide (PINP), matrix metalloproteinase (MMP 1, MMP 9) and a tissue inhibitor of matrix metalloproteinase (TIMP 1) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) were measured and compared with healthy controls. The relationship between these serum markers, echocardiographic and cardiac magnetic resonance parameters and the outcome at a follow-up of 61 months (range, 24–85 months) was determined.

Results

Compared with the healthy control group, the study group had significantly higher levels of TIMP1, PIIINP, CITP, PINP and NT-pro-BNP (p<0.05, each). The levels of PIIINP and CITP were significantly higher among patients with an SRV mass index above the mean value. The level of PIIINP was significantly higher among patients with an SRV EDV index above the mean value. CITP was significantly elevated in SRV late gadolinium enhanced (LGE) positive patients, compared to patients without SRV LGE. MMP9 and TIMP1 predicted an adverse clinical outcome on univariate Cox proportional hazard survival analysis in addition to well proven predictors of outcome (SRV EF and NYHA).

Conclusions

We demonstrated a pattern of altered collagen turnover adversely related with the indices of SRV remodeling and an adverse clinical outcome in patients with SRV.

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.

Outcomes after Arterial Switch Operation for Simple Transposition

Without intervention, babies born with transposed great arteries (TGA) are doomed to a rapid death. Jatene and coworkers deserve the credit for performing the first successful arterial switch operation (ASO) in a patient with TGA and ventricular septal defect (VSD) in 1975. Since then ASO has become the procedure of choice in most medical centers. This review article summarizes the historical aspects of arterial switch operation and assesses this procedure's outcomes.

Usefulness of Percutaneous Transluminal Coronary Balloon Angioplasty for the Left Coronary Artery Stenosis 10 Years More Than After Arterial Switch Operation

Proximal stenosis adjacent to the orifice of one or both coronary arteries may occur after the arterial switch operation (ASO) for d-transposition of the great arteries (d-TGA). Coronary artery stenosis (CAS) often progresses within the first 6 months postoperatively and may result in myocardial ischemia and infarction. Although percutaneous transluminal coronary balloon angioplasty (PCBA) for CAS within 15 months after ASO for d-TGA has been reported, there is no report of PCBA for CAS in the late period after ASO. We present the results of PCBA for CAS of the left coronary artery performed more than 10 years after ASO in an 11-year-old boy and a 14-year-old boy without complication. The stenosis degree improved in both patients from 81 to 45 and 80 to 54 %, respectively. Restenosis did not occur, and the stenosis degree improved to about 25 % late after PCBA. Although the initial effect of PCBA may not be dramatic, it can improve late after PCBA. It was considered that the optimal balloon-reference vessel ratio was about 1.0, to obtain the minimal effective lumen diameter. PCBA for CAS even if performed many years after ASO is feasible without complication. PCBA can also provide delayed improvement late after the procedure.

Chronological changes in stenosis of translocated coronary arteries on angiography after the arterial switch operation in children with transposition of the great arteries: comparison of myocardial scintigraphy and angiographic findings

BACKGROUND

The peri-operative mortality of the arterial switch operation in neonates with transposition of the great arteries is considerably low; however, long-term outcomes of translocated coronary arteries still remain one of the most crucial issues. Methods and results A total of 110 neonates with transposition of the great arteries after arterial switch operation were evaluated; three (2.7%) late deaths occurred. The remaining 107 patients except for one underwent follow-up angiography. Angiography showed coronary artery stenosis in nine (8.4%), with right coronary artery lesions in two and left main trunk lesions in seven. In two patients, right coronary artery stenosis regressed during follow-up. In left main trunk lesions, the severity of stenosis improved in four, did not change in one, and progressed to total occlusion in two patients. In children with coronary artery stenosis, myocardial scintigraphy showed perfusion defects in five out of six (83%) with left main trunk with ⩾75% stenosis and in four out of four with left main trunk stenosis ⩾90%. In contrast, patients whose coronary artery stenosis disappeared during follow-up had no perfusion defects on scintigraphy.

CONCLUSIONS

Regression of ostial stenosis of the transplanted coronary artery on angiogram was observed. The stenosis regressed over time in six patients; two coronary arteries with 99% stenosis and delayed angiographic enhancement of the distal coronary artery resulted in total occlusion within 1 year after the arterial switch operation. Combination of angiography and myocardial scintigraphy could be useful to differentiate deceptive stenosis from progressive stenosis.

Arterial Switch for Transposition of the Great Arteries With Large Ventricular Septal Defect and for Taussig Bing Anomaly: Experience From a Tertiary Care Center in the Developing World

BACKGROUND

Results of the arterial switch operation (ASO) for transposition of the great arteries (TGA) with large ventricular septal defect (VSD) and for Taussig Bing anomaly (TBA) in a tertiary care center of a developing country were retrospectively analyzed.

METHODS

From January 2007 through June 2013, a total of 30 patients with TBA and 54 patients having TGA with large VSD underwent ASO with VSD closure. Age at surgery for TBA was 27 days to 7 years (median age 3 months) and for TGA with VSD it was 1 day to 6 years (median age 2 months). In all, 46.7% of patients with TBA and 30% of patients with TGA/VSD presented with sepsis secondary to pneumonitis and were taken for surgery when the infection was under control. In all, 13% of patients with TBA and 5.5% of patients with TGA/VSD were on intermittent positive pressure ventilation (IPPV) prior to and continuing up to the time of surgery.

RESULTS

On multivariate analysis, factors associated with mortality were the presence of preoperative IPPV for pneumonia (P < .006) and the need for peritoneal dialysis following surgery (P < .028). Neither diagnosis of TBA or TGA/VSD nor any associated anatomical feature (including aortic arch obstruction, unusual coronary anatomy, great artery relationship, or mitral valve anomaly) was found to be related to high early mortality or late complications. Follow-up was 92% complete, with a mean duration of follow-up of 4.1 years. Freedom from reoperation was 98% at five years, and actuarial survival was 83.3% at five years.

CONCLUSIONS

Our experience at a tertiary center in a developing country suggests that preoperative need for IPPV for pneumonia is a major determining factor for mortality and morbidity in patients undergoing ASO for TBA and TGA/VSD. This appears to be of greater consequence than details of the underlying disease per se.

Arterioplasty for Right Ventricular Outflow Tract Obstruction After Arterial Switch Is a Durable Procedure

BACKGROUND

Right ventricular outflow tract obstruction (RVOT) is the most common late complication requiring intervention after arterial switch operation (ASO). The durability of surgical management of this complication has not been well established.

METHODS

We retrospectively reviewed the charts of 38 consecutive patients who underwent RVOT reconstruction after ASO at our institution between 2004 and 2013. During the same time period, 223 consecutive patients underwent ASO for transposition of the great arteries at our institution. Thirty-five (16%) of the 223 patients developed RVOT obstruction, and 3 additional patients who had ASO done elsewhere presented to us with RVOT obstruction. Patient characteristics, site of stenosis, type of intervention, and outcomes were analyzed. Data are presented as median with interquartile ranges.

RESULTS

The time interval between ASO and echocardiographic diagnosis of significant RVOT obstruction was 12.5 (3 to 23.7) months. After echocardiographic diagnosis, 33 (87%) children underwent cardiac catheterization. Obstruction involved the supravalvar main pulmonary artery (PA) in 21 (64%), branch PA in 14 (42%), pulmonary valve in 4 (12%), and sub-valvar area in 1 (3%). Ten of 33 patients who underwent catheterization had attempted percutaneous intervention, with 4 (40%) demonstrating significant response. Surgical intervention was performed at a median of 4 months in responders compared with 2.3 months in non-responders. Surgical repair included main PA plasty (36), extended to 1 or both branch PAs (26), or crossed the RVOT annulus (7). Surgical morbidity was 13% and there was no hospital or late mortality. At last follow-up, 41.2 months (21.4 to 81) after RVOT reconstruction, all patients had New York Heart Association grade 0 or 1 symptoms, and RV pressure was a median 36% of systemic pressure. Five (13%) patients underwent catheterization 26 months after surgery, with 2 requiring dilation at site of arterioplasty and 3 requiring distal branch PA intervention. One patient required reoperation for main PA stenosis. Freedom from re-intervention after surgery is 89%, 86%, and 86% at 2, 3, and 5 years, respectively.

CONCLUSIONS

Surgical management of RVOT obstruction after ASO is an effective and durable intervention in the intermediate term. Our results serve as a benchmark for expected outcomes in this disease process.

Midterm outcome of primary arterial switch operation beyond six weeks of life in children with transposition of great arteries and intact ventricular septum

BACKGROUND

We have previously reported our experience in primary arterial switch operation (ASO) in children more than six weeks with transposition of great arteries and intact ventricular septum (TGA/IVS). The upper age limit for performing an ASO in these children is not yet settled and reports regarding outcome of ASO in these children are few. In this prospective observational study, we report the midterm results of children with TGA-IVS older than six weeks undergoing primary ASO.

METHODS

A total of 109 children aged more than 6 weeks with median age of 60 days (range 42-3,000 days), with regressed left ventricle underwent primary ASO. Extracorporeal membrane oxygenation was used in 20% (22 of 109) of them; 90.8% (99 of 109) of children who survived were prospectively followed, with a mean follow-up of 28 months (range 18-84 months).

RESULTS

Two late deaths occurred, and survival in the remainder was estimated to be 98% at seven years. The incidence of aortic regurgitation (AR) was found to have a decreasing trend with freedom from AR approaching 100% by 34 months. The left ventricular shape and function returned to normal within one to three months following surgery. None of these children had any rhythm disturbances or evidence of myocardial ischemia.

CONCLUSIONS

Primary ASO can be safely performed in children with regressed ventricle, irrespective of age with encouraging results. The midterm results of these children are comparable in terms of survival and freedom from complications associated with preserved ventricle.

Neonatal aortic stenosis

Neonatal aortic stenosis is a complex and heterogeneous condition, defined as left ventricular outflow tract obstruction at valvular level, presenting and often requiring treatment in the first month of life. Initial presentation may be catastrophic, necessitating hemodynamic, respiratory and metabolic resuscitation. Subsequent management is focused on maintaining systemic blood flow, either via a univentricular Norwood palliation or a biventricular route, in which the effective aortic valve area is increased by balloon dilation or surgical valvotomy. In infants with aortic annular hypoplasia but adequately sized left ventricle, the Ross-Konno procedure is also an attractive option. Outcomes after biventricular management have improved in recent years as a consequence of better patient selection, perioperative management and advances in catheter technology. Exciting new developments are likely to significantly modify the natural history of this disorder, including fetal intervention for the salvage of the hypoplastic left ventricle; 3D echocardiography providing better definition of valve morphology and aiding patient selection for a surgical or catheter-based intervention; and new transcutaneous approaches, such as duel beam echo, to perforate the valve.

Characteristics and outcomes of transposition of great arteries in the neonatal period

INTRODUCTION AND OBJECTIVES

Transposition of the great arteries is a prevalent congenital heart defect with a high survival rate and a good long-term outcome, especially if managed with early surgical intervention during the neonatal period. In this study, our main objective was to describe patient characteristics and outcomes and to identify possible predictors of early and long-term morbidity and mortality.

METHODS

Retrospective analysis through review of clinical and surgical charts of patients with transposition of the great arteries admitted to the service of neonatology during 2000-2011.

RESULTS

The study included 136 patients; 119 of them had undergone corrective surgery during the neonatal period. Patients were divided into 3 groups: group I, 81 cases of isolated transposition; group II, 24 cases with ventricular septal defect; and group III, 31 with "complex" transposition of the great arteries. The overall postoperative survival was 96.7% (115 of 119 patients); no patients from group I died after surgery. Duration of surgery, intubation, inotropic treatment, and length of stay were higher in patients in groups II and III. The overall survival rate after an average of 6 years of follow-up was 90.4% 123 of 136 patients, with no deaths after discharge in group I. The most frequent residual defect during cardiac follow-up was supravalvular pulmonary stenosis, in 33 of 113 patients that had follow-up data.

CONCLUSIONS

In our study, the survival rate was high in patients with transposition of great arteries and especially in those undergoing arterial switch. The number of subsequent residual heart defects was low.

Anesthetic management of a child with corrected transposition of great vessels undergoing non-cardiac surgery

We describe the successful anesthetic management of a 14-year-old child, a corrected case of transposition of great vessels in childhood and presently with residual atrial septal defect, peripheral cyanosis, and neurological deficit of lower limb presented for tendoachillis lengthening.

Comparison of late results of arterial switch versus atrial switch (mustard procedure) operation for transposition of the great arteries

Two decades after surgery for transposition of the great arteries, the clinical status, cardiac function, cardiorespiratory performance, and neurohormonal activity of patients who underwent either atrial switch (Mustard) operations or arterial switch operations (ASOs) were compared. Sixty-two patients with simple transposition of the great arteries who underwent either Mustard (n = 34) or ASO (n = 28) procedures were included in this cross-sectional study. Following the same study protocol, clinical workup including echocardiography, stress testing, and blood work was completed for all patients. Mean ages in the 2 groups were comparable, at 20.6 ± 2.1 and 20.6 ± 3.4 years in the ASO and Mustard groups, respectively. All ASO patients were in New York Heart Association class I, whereas 59% of Mustard patients were in class II or III. Peak oxygen uptake was higher in ASO patients (percentage of predicted 80% vs 69%, p <0.01). Compared with healthy subjects, the mean Tei index for systemic ventricle was high in the 2 groups, but this parameter was significantly higher in Mustard than ASO patients (0.60 ± 0.16 vs 0.47 ± 0.14, p <0.01). The median plasma N-terminal pro-brain natriuretic peptide level in ASO patients was within the normal range, but the Mustard group had significantly higher levels (42 ng/ml [range 18 to 323] vs 172 ng/ml [range 26 to 1,018], p <0.0001). In conclusion, this cross-sectional assessment 2 decades after surgery reveals better clinical status in patients who underwent ASO compared with Mustard patients. This holds in terms of cardiac function, cardiorespiratory performance, and neurohormonal activity.

Cardiovascular outcomes after the arterial switch operation for D-transposition of the great arteries

BACKGROUND

Data regarding long-term outcomes after the arterial switch operation for D-transposition of the great arteries are scarce.

METHODS AND RESULTS

A single-institution retrospective cohort study was conducted to assess cardiovascular outcomes after an arterial switch operation between 1983 and 1999. Patients without follow-up visits within 3 years were contacted and secondary sources of information obtained. Overall, 400 patients, 154 (38.3%) with a ventricular septal defect, 238 (59.5%) with an intact septum, and 9 (2.3%) with a Taussig-Bing anomaly, were followed for a median of 18.7 years. In perioperative survivors, overall and arrhythmia-free survival rates at 25 years were 96.7±1.8% and 96.6±0.1%, respectively. Late mortality was predominantly a result of sudden deaths and myocardial infarction. At 25 years, 75.5±2.5% remained free from surgical or catheter-based reintervention. Freedom from an adverse cardiovascular event was 92.9±1.9% at 25 years. Independent predictors were a single right coronary artery (hazard ratio, 4.58; 95% confidence interval, 1.32-15.90), P=0.0166) and postoperative heart failure (hazard ratio, 6.93; 95% confidence interval, 1.57-30.62; P=0.0107). At last follow-up, the left ventricular ejection fraction was 60.3±8.9%, 97.3% had class I symptoms, and 5.2% obstructive coronary artery disease. Peak oxygen uptake was 35.1±7.6 mL/kg/min (86.1±15.1% predicted), with a chronotropic index <80% in 34.2%. At least moderate neoaortic and pulmonary regurgitation were present in 3.4% and 6.6%, respectively, and more than mild neoaortic and pulmonary stenosis in 3.2% and 10.3%.

CONCLUSIONS

Long-term and arrhythmia-free survival is excellent after arterial switch operation. Although sequelae include chronotropic incompetence and neoaortic, pulmonary, and coronary artery complications, most patients maintain normal systolic function and exercise capacity.

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.

Midterm results after arterial switch operation for transposition of the great arteries: a single centre experience

Background

The arterial switch operation (ASO) has become the surgical approach of choice for d-transposition of the great arteries (d-TGA). There is, however an increased incidence of midterm and longterm adverse sequelae in some survivors. In order to evaluate operative risk and midterm outcome in this population, we reviewed patients who underwent ASO for TGA at our centre.

Methods

In this retrospective study 52 consecutive patients with TGA who underwent ASO between 04/1991 and 12/1999 were included. To analyze the predictors for mortality and adverse events (coronary stenoses, distortion of the pulmonary arteries, dilatation of the neoaortic root, and aortic regurgitation), a multivariate analysis was performed. The follow-up time was ranged from 1–10 years (mean 5 years, cumulative 260 patient-years).

Results

All over mortality rate was 15.4% and was only observed in the early postoperative period till 1994. The predictors for poor operative survival were low APGAR-score, older age at surgery, and necessity of associated surgical procedures. Late re-operations were necessary in 6 patients (13.6%) and included a pulmonary artery patch enlargement due to supravalvular stenosis (n = 3), coronary revascularisation due to coronary stenosis in a coronary anatomy type E, aortic valve replacement due to neoaortic valve regurgitation (n = 2), and patch-plasty of a pulmonary vein due to obstruction (n = 1). The dilatation of neoaortic root was not observed in the follow up.

Conclusions

ASO remains the procedure of choice for TGA with acceptable early and late outcome in terms of overall survival and freedom of reoperation. Although ASO is often complex and may be associated with morbidity, most patients survived without major complications even in a small centre.