Midterm Assessment of the Reconstructed Arteries After the Arterial Switch Operation

Neoaortic Regurgitation Detected by Echocardiography After Arterial Switch Operation: A Systematic Review and Meta-Analysis

Background

Neoaortic root dilatation (NeoARD) and neoaortic regurgitation (NeoAR) are common sequelae following the arterial switch operation (ASO) for transposition of the great arteries.

Objectives

The authors aimed to estimate the cumulative incidence of NeoAR, assess whether larger neoaortic root dimensions were associated with NeoAR, and evaluate factors associated with the development of NeoAR during long-term follow-up.

Methods

Electronic databases were systematically searched for articles that assessed NeoAR and NeoARD after ASO, published before November 2022. The primary outcome was NeoAR, classified based on severity categories (trace, mild, moderate, and severe). Cumulative incidence was estimated from Kaplan-Meier curves, neoaortic root dimensions using Z-scores, and risk factors were evaluated using random-effects meta-analysis.

Results

Thirty publications, comprising a total of 6,169 patients, were included in this review. Pooled estimated cumulative incidence of ≥mild NeoAR and ≥moderate NeoAR at 30-year follow-up were 67.5% and 21.4%, respectively. At last follow-up, neoaortic Z-scores were larger at the annulus (mean difference [MD]: 1.17, 95% CI: 0.52-1.82, P < 0.001; MD: 1.38, 95% CI: 0.46-2.30, P = 0.003) and root (MD: 1.83, 95% CI: 1.16-2.49, P < 0.001; MD: 1.84, 95% CI: 1.07-2.60, P < 0.001) in patients with ≥mild and ≥moderate NeoAR, respectively, compared to those without NeoAR. Risk factors for the development of any NeoAR included prior pulmonary artery banding, presence of a ventricular septal defect, aorto-pulmonary mismatch, a bicuspid pulmonary valve, and NeoAR at discharge.

Conclusions

The risks of NeoARD and NeoAR increase over time following ASO surgery. Identified risk factors for NeoAR may alert the clinician that closer follow-up is needed. (Risk factors for neoaortic valve regurgitation after arterial switch operation: a meta-analysis; CRD42022373214).

Neo-aortic posterior sinus of Valsalva reduction and closed coronary artery transfer as a method to approach aortopulmonary mismatch in transposition of great arteries

OBJECTIVE

In transposition of great arteries (TGA), aortopulmonary mismatch (APM) can determine postoperative neo-aortic insufficiency after arterial switch operation (ASO). The distortion of sinu-tubular junction may be the geometric mechanism responsible. We developed a strategy able to reduce the mismatch at the timing of ASO, and in this study, we aimed to describe our indications and results.

METHODS

Preoperative root circumferences at the level of the mid-portion of sinus of Valsalva and ascending aorta circumference were used to define APM. Indication to surgery was a neo-aortic root (NAR) to ascending aorta ratio ≥ 1.4. Along with standard ASO, posterior neo-aortic sinus inverted conal resection and punch technique for coronary reimplantation was used in all patients to re-establish the more geometric ratio possible between the two components. Hypoplastic aortic arch (HAA) and aortic coarctation (CA) were managed by aortic arch enlargement with an autologous pericardial patch.

RESULTS

Twenty patients (20 male), 19 with diagnoses TGA (17 with ventricular septal defect, 85%) and 1 with Taussig-Bing anomaly underwent ASO. HAA was present in three (15%) and CA in two (10%). The mean preoperative neo-aortic to ascending aorta ratio was 1.8 versus 1.1 postoperatively (p < .01). No moderate or severe neo-aortic insufficiency was observed before discharge and at a mean follow-up of 4.3 years (interquartile range = 0.5-12 years).

CONCLUSION

Neo-aortic reduction plasty with coronary reimplantation by punch technique is an effective strategy to approach preoperative APM in TGA. This technique confers a more harmonious geometry to NAR that can improve neo-aortic valve function.

Reference Values for Ventricular Volumes and Pulmonary Artery Dimensions in Pediatric Patients with Transposition of the Great Arteries After Arterial Switch Operation

BACKGROUND

Pulmonary artery (PA) anatomy in patients with transposition of the great arteries (TGA) after arterial switch operation (ASO) with Lecompte manoeuvre is different compared to healthy subjects, and stenoses of the PA are common. Magnetic resonance imaging (MRI) is an excellent imaging modality to assess PA anatomy in TGA patients. However, disease-specific reference values for PA size are scarce.

PURPOSE

To establish disease-specific reference ranges for PA dimensions and for biventricular volumes and mass.

STUDY TYPE

Retrospective.

SUBJECTS

A total of 69 pediatric patients with TGA after ASO (median age 12.6 years; range 5-17.8 years; 13 females and 56 males).

FIELD STRENGTH/SEQUENCE

3.0 T, steady-state free precession (SSFP) and gradient echo cine sequences and four-dimensional time-resolved magnetic resonance angiography with keyhole.

ASSESSMENT

Right and left PA (RPA, LPA) were each measured at three locations during its course around the aorta. Ventricular volumes, mass, and ejection fraction were measured from a stack of short axis cine images.

STATISTICAL TESTS

The lambda-mu-sigma (LMS) method of Cole and Green, univariate and multivariate linear models, and t-test.

RESULTS

Centile graphs and tables for PA dimensions, biventricular volumes, mass, and ejection fraction were created. Univariate linear analysis showed significant associations (P < 0.05) between body surface area (BSA), height, and weight with systolic MPA and RPA diameter. In multivariate linear analysis, only BSA remained a strong predictor for main PA and RPA diameters. For biventricular volumes, the univariate linear model revealed a strong influence of BSA, height, weight, and age (all P < 0.05). On multivariate linear analysis, only body height remained associated.

DATA CONCLUSION

Uni- and multivariate linear analyses showed a strong association between BSA and PA diameters, as well as between height and biventricular volumes, and therefore, centile tables and graphs are presented accordingly. Our data may improve MR image interpretation and may serve as a reference in future studies.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY STAGE: 2.

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

Background and Objectives

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

Methods

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

Results

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

Conclusion

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

Anatomic Risk Factors for Reintervention After Arterial Switch Operation for Taussig-Bing Anomaly

BACKGROUND

This study aimed to determine the factors related to reintervention, especially for pulmonary stenosis (PS), in patients with Taussig-Bing anomaly (TBA) after the arterial switch operation.

METHODS

This retrospective study included 34 patients with TBA who underwent the arterial switch operation between 1993 and 2018. Preoperative anatomic and physiologic differences and long-term outcomes were determined using a case-matched control with transposition of the great arteries with ventricular septal defect and TBA with an anterior and rightward aorta.

RESULTS

At arterial switch operation, median age was 43 days (range, 16 to 102) and median body weight was 3.6 kg (range, 2.8 to 3.8 kg). Aortic arch obstruction and coronary anomalies were present in 64% and 41% of patients, respectively. The hospital mortality rate was 11%, including one cardiac death, and the late mortality rate was 2.9%. Furthermore, 41% patients underwent 26 reinterventions for PS. Patients undergoing PS-related reintervention had a significantly larger native pulmonary artery to aortic annulus size ratio than patients not receiving reintervention (1.69 vs 1.41, P = .02). This ratio was the only predictor of PS-related reintervention; it was significantly higher in the TBA group than in the transposition of great arteries/ventricular septal defect group. The PS-related reintervention was required more in the TBA group than in the transposition of great arteries/ventricular septal defect group.

CONCLUSIONS

Regardless of complex coronary anatomy and associated anomalies, early and late survival were acceptable. Postoperative PS was strongly associated with having a larger native pulmonary valve, suggesting that an optimal surgical reconstruction was required for achieving an appropriate aortopulmonary anatomic relationship during the arterial switch operation.

Progression of aortic root dilatation and aortic valve regurgitation after the arterial switch operation

Objective

To study neo-aortic growth and the evolution of neo-aortic valve regurgitation (AR) in patients with transposition of the great arteries (TGA) after arterial switch operation (ASO) from newborn to adulthood and to identify patients at risk.

Methods

Neo-aortic dimensions (annulus/root/sinotubular junction) and neo-aortic valve regurgitation were assessed serially in 345 patients with TGA who underwent ASO between 1977 and 2015. Linear mixed-effect models were used to assess increase of neo-aortic dimensions over time and to identify risk factors for dilatation. Risk factor analysis for AR by using time-dependent Cox regression models.

Results

After a rapid increase in the first year after ASO and proportional growth in childhood, neo-aortic dimensions continue to increase in adulthood without stabilisation. Annual diameter increase in adulthood was 0.39±0.06, 0.63±0.09 and 0.54±0.11 mm for, respectively, neo-aortic annulus, root and sinotubular junction, all significantly exceeding normal growth. AR continues to develop over time: freedom from AR ≥moderate during the first 25 years post-ASO was 69%. Risk factors for root dilatation were complex TGA anatomy (TGA-ventricular septal defect (VSD), double outlet right ventricle with subpulmonary VSD) and male gender. Risk factors for AR ≥moderate were: complex TGA anatomy and neo-aortic growth. Per millimetre increase in aortic root dimension, there was a 9% increase in the hazard of AR ≥moderate. Bicuspid pulmonary valve did not relate to the presence of root dilatation or AR.

Conclusion

After ASO, neo-aortic dilatation proceeds beyond childhood and is associated with an increase in AR incidence over time. Careful follow-up of the neo-aortic valve and root function is mandatory, especially in males and in patients with complex TGA anatomy.

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.

Balloon angioplasty for supravalvular aortic stenosis as an early complication following arterial switch operation

Supravalvular aortic stenosis as an early complication of transposition of the great artery repair is rare with few cases reported. Furthermore, transcatheter intervention is uncommon as surgical re-intervention has been traditionally done. We describe two cases of supravalvular aortic stenosis at the anastomotic site as an early complication of the arterial switch operation. Both patients underwent balloon angioplasty of the supravalvular aorta with improvement in postangioplasty gradients and angiographic appearance. Both patients at short-term follow-up had persistent improved gradient without need for further intervention.

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.

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.

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.

Surgery for transposition of great arteries: A historical perspective

The history of surgery for transposition of great arteries (TGA) has paralleled the history of cardiac surgery. In fact, it began before the birth of open heart surgery when the palliative Blalock–Hanlon septectomy was first performed in 1948. The atrial switch, which was an attempt to correct the physiology of transposition, had significant shortcomings. The arterial switch sought to address them. This has emerged as an anatomically as well as physiologically appropriate solution. Today we continue to pursue technical refinements as well as try to expand the indications of the arterial switch. This review traces the various milestones in this perpetual journey.

Supravalvular aortic stenosis after arterial switch operation

Supravalvular aortic stenosis as a late complication of transposition of the great arteries is very rare, and only a few cases have been reported. We describe the case of a 14-year-old girl who developed supravalvular aortic stenosis as a late complication of the arterial switch operation for transposition of the great arteries. The narrowed ascending aorta was replaced with a graft. The right pulmonary artery was transected to approach the ascending aorta which adhered severely to the main pulmonary trunk, and we obtained a good operative field.

Aortopathy associated with congenital heart disease: A current literature review

In patients born with congenital heart disease, dilatation of the aorta is a frequent feature at presentation and during follow-up after surgical intervention. This review provides an overview of the pathologies associated with aortopathy, and discusses the current knowledge on pathophysiology, evolution, and treatment guidelines of the aortic disease associated with congenital heart defects.

Recurrent neoaortic insufficiency after the switch back operation with previous repair of transposition with ventricular septal defect and aortic arch hypoplasia

Neoaortic insufficiency is not uncommon after the arterial switch operation (ASO) for d-Transposition, yet surgery is rarely required. In a patient with worsening neoaortic regurgitation post-arterial switch and ventricular septal defect (VSD) closure, we performed a successful "switch back" operation with documented aortic valve competence on discharge echocardiography. However, recurrent severe aortic insufficiency required valve replacement, and histopathology of the excised valve indicated abnormal leaflet/vascular wall structure. We question whether the switch back operation is a viable option for neoaortic insufficiency after an ASO in patients with previous d-Transposition and VSD, when the native pulmonary valve may have structural deficiencies.

Late complications and pathological findings of the arterial switch operation

We describe aortic root dilatation, severe aortic regurgitation, and pulmonary artery stenosis that were accidentally diagnosed 23 years after the arterial switch operation for transposition of the great arteries in situs inversus. We successfully performed the modified Bentall procedure and pulmonary artery reconstruction. The pathology of the dilated aortic root revealed intimal atherosclerosis and linear necrosis of the tunica media, suggesting the vulnerability of the pulmonary artery to systemic pressure.

Stenosis of the branches of the neopulmonary artery after the arterial switch operation: A cardiac magnetic resonance imaging study

Background:

The neonatal arterial switch operation (ASO) is now the standard of care for children born with transposition of the great arteries. Stenosis of the neopulmonary artery on long-term follow up is a known complication.

Methods:

We performed a retrospective analysis of eleven patients who underwent a cardiac magnetic resonance imaging (MRI) due to echocardiographic evidence suggestive of stenosis of the neopulmonary artery or its branches (mean estimated Doppler gradient 48 mmHg, min 30 mmHg, max 70 mmHg). A comprehensive evaluation of anatomy and perfusion was done by cardiac MRI.

Results:

The branches of the neopulmonary artery (neo PA) showed decreased caliber in three patients unilaterally and in two patients, bilaterally. Magnetic resonance (MR) perfusion studies showed concomitant decreased flow, with discrepancy between the two lungs of 35/65% or worse, only in the three patients with unilateral obstruction, by two different MR perfusion methods.

Conclusions:

Cardiac MR can be used as a comprehensive non-invasive imaging technique to diagnose stenosis of the branches of the neopulmonary after the ASO, allowing evaluation of anatomy and function of the neoPA, its branches, and the differential perfusion to each lung, thus facilitating clinical decision making.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Canadian Cardiovascular Society 2009 Consensus Conference on the management of adults with congenital heart disease: complex congenital cardiac lesions

With advances in pediatric cardiology and cardiac surgery, the population of adults with congenital heart disease (CHD) has increased. In the current era, there are more adults with CHD than children. This population has many unique issues and needs. They have distinctive forms of heart failure and their cardiac disease can be associated with pulmonary hypertension, thromboemboli, complex arrhythmias and sudden death. Medical aspects that need to be considered relate to the long-term and multisystemic effects of single ventricle physiology, cyanosis, systemic right ventricles, complex intracardiac baffles and failing subpulmonary right ventricles. Since the 2001 Canadian Cardiovascular Society Consensus Conference report on the management of adults with CHD, there have been significant advances in the field of adult CHD. Therefore, new clinical guidelines have been written by Canadian adult CHD physicians in collaboration with an international panel of experts in the field. Part III of the guidelines includes recommendations for the care of patients with complete transposition of the great arteries, congenitally corrected transposition of the great arteries, Fontan operations and single ventricles, Eisenmenger's syndrome, and cyanotic heart disease. Topics addressed include genetics, clinical outcomes, recommended diagnostic workup, surgical and interventional options, treatment of arrhythmias, assessment of pregnancy risk and follow-up requirements. The complete document consists of four manuscripts, which are published online in the present issue of The Canadian Journal of Cardiology. The complete document and references can also be found at www.ccs.ca or www.cachnet.org.