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

Outcomes of coronary artery obstructions after the arterial switch operation for transposition of the great arteries

OBJECTIVE

Coronary obstruction is a rare but common complication of the arterial switch operation for transposition of the great arteries. The majority of patients remain asymptomatic and no risk factors allow targeting for reinforced surveillance. We aim to review the natural history of patients diagnosed with coronary obstruction after arterial switch operation for transposition of the great arteries and occurrence of coronary-related outcomes.

METHODS

We retrospectively reviewed medical records of the 102 patients diagnosed with coronary obstruction after arterial switch operation for transposition of the great arteries in our institution from 1981 to 2022. Outcomes were anti-ischemic treatment introduction, revascularization (surgical or percutaneous angioplasty), and death; investigations that motivated revascularization were also reviewed.

RESULTS

Twenty-eight out of 102 patients presented with myocardial ischemia during the immediate postoperative phase, 31 were diagnosed when symptomatic, and 43 were identified at the presymptomatic stage, according to our screening policy in preschool-aged children. Stenosis-related event occurrence was, respectively, 29 out of 31 and 32 out of 43 in the latter 2 subgroups. Coronary-related mortality reached 10% in patients diagnosed when symptomatic; no patients died in the presymptomatic subgroup. Of the 28 low-risk patients with no signs of ischemia at diagnosis, 10 developed obstruction warranting reintervention during follow-up. Revascularization was motivated by appearance of symptoms in patients with severe stenosis in normal coronary dispositions, and by clinical symptoms or documented silent ischemia in abnormal coronary patterns.

CONCLUSIONS

Occurrence of stenosis-related events remains significant in patients after arterial switch operation, underlining the importance of early diagnosis for timely intervention. Initial anatomical evaluation identifies stenotic and at-risk patients; this will require periodical function testing. Follow-up modalities can be tailored to a patient's individual anatomic characteristics.

Exercise electrocardiogram for risk-based screening of severe residual coronary lesion in children after coronary surgery

BACKGROUND

Residual severe coronary artery (CA) lesion (SCL) in children after cardiac surgery involving the CA is a major concern.

AIM

To evaluate the value of exercise electrocardiogram (eECG) for risk-based screening of SCL.

METHODS

We analysed 135 maximal eECG from 115 children (mean age 13.6±3.7 years) who underwent concomitant CA imaging. SCL was defined as a stenosis exceeding 50%.

RESULTS

Underlying congenital heart diseases were transposition of the great arteries (TGA) (n = 116), CA pathway anomaly (n = 13) and left CA from the pulmonary artery (n = 6). Eleven SCLs were identified in 10 patients, of which 3 had a known untreated non-severe lesion and 4 had no lesions on previous imaging. In multivariable analysis, risks markers for SCL were effort chest pain (OR: 4.72, 95% CI: 1.23-18.17; P=0.024), intramural pathway (OR: 4.37, 95% CI: 1.14-16.81; P=0.032). Yacoubs C-type CA was added as a risk marker for patients with TGA (P=0.0009). All patients with SCL had a positive eECG (sensitivity: 100%, 95% CI: 72-100). Specificity was 81% (95% CI: 73-87). In the low-risk group (0 risk markers), 3/95 patients had SCL (3%), and the post-test probability of SCL with positive eECG (PPr+) was 15% (95% CI: 8-21). In the high-risk group (≥1 risk marker) comprising 8/40 SCLs (20%), PPr+ was 53% (95% CI: 35-67).

CONCLUSIONS

Most SCL tended to develop gradually, years after surgery. Provided it is near maximal, a negative eECG appears sufficient to exclude SCL. In the high-risk group, PPr+ exceeded 50%.

Anatomical reconstruction of proximal coronary artery stenosis in children

OBJECTIVES

Timing and method of surgical reconstruction for non-sclerotic proximal coronary artery stenosis, occuring de-novo or post coronary artery transfer, are evolving. We have pursued a technique of anatomical reconstruction of ostial and short segment proximal coronary artery stenosis and atresia in children, using patch plasty or interposition vein graft. Herein, we discuss the medium- to long-term outcome.

METHODS

Nine consecutive children undergoing ten left main coronary artery reconstructions using autologous great saphenous vein patch (n = 4), autologous pericardium (n = 4), xenopericardium (n = 1) or great saphenous vein interposition graft (n = 1) were retrospectively analysed. Complementary wedge resection of the stenotic coronary ostium was performed in chronic cases.

RESULTS

The aetiology of coronary artery stenosis was post arterial switch operation (n = 6), Takayasu`s arteritis (n = 1), idiopathic left main coronary artery atresia (n = 1) and anomalous origin of the left coronary artery from the pulmonary artery (n = 1). Median age and weight at operation were 0.15 (range 0.01-13.1) years and 4.4 (range 3 -13.1) kilograms, respectively. Survival was 100% at median follow-up of 12.6 (range 1-19.2) years. All patients showed normal left ventricular ejection fraction on transthoracic echocardiogram. In one patient, kinking of the proximal left circumflex artery resulted in non-significant obstruction. In all other cases, follow-up catheter angiography revealed unobstructed coronary arteries. Cardiac magnetic resonance tomography showed no significant perfusion deficit in any child.

CONCLUSIONS

Anatomical reconstruction of the proximal left coronary artery using autologous saphenous vein may allow optimal restoration of physiological coronary blood flow, keeping the option of future coronary bypass operation open.

Cardiovascular Prevention Among Young Adults with Congenital Heart Disease

PURPOSE OF REVIEW

There are over a million adults living with congenital heart disease (CHD) in the USA. There have been improvements in CHD management which have led to an expansion of the adult congenital heart disease (ACHD) population. There is a high prevalence of atherosclerotic cardiovascular disease (ASCVD) encountered in the aging ACHD population. This review focuses on the most recent literature regarding the primary prevention of ASCVD in young ACHD patients.

RECENT FINDINGS

There are unique considerations for ASCVD risk reduction in ACHD patients. ASCVD may be as prevalent in ACHD compared in the general population. However, there may be a perceived shorter life expectancy in ACHD patients; therefore, primary prevention of ASCVD may not be considered important. Preventative strategies for ASCVD are underutilized in ACHD patients. As these patients are followed for a lifetime by cardiologists, we can truly pursue primary prevention in this aging population.

Coronary Interventions in Pediatric Congenital Heart Disease

Coronary artery lesions represent rare conditions in pediatric congenital heart disease and mainly include coronary artery stenoses (CAS) or coronary artery fistulae (CAF). Due to the small vessel size, pediatric percutaneous coronary interventions (PCI) are demanding and studies concerning long-term results are missing. In this retrospective study, we analyzed indications, procedural details, and post-procedural outcomes in pediatric patients who underwent PCI in our institution. For CAS treatment, procedural success was defined as efficient coronary revascularization with a significant improvement of coronary perfusion. CAF treatment was considered successful, when no residual shunt was detectable. From 1995 to 2020, 32 pediatric patients aged ≤ 18 years received interventional treatment for CAS (n = 24/32) or CAF (n = 8/32). Reasons for CAS were post-surgical (n = 15/24) or post-transplant (n = 9/24). Interventional treatment strategies included coronary angioplasty (20/43), stent placement (10/43), and a combination of both (13/43). In-hospital mortality occurred in 6/24 patients and late mortality in 5/24 patients leading to an overall 5-year survival of 62.5%. Early mortality mainly occurred due to post-ischemic myocardial failure. CAF occlusion was performed using coil embolization (n = 3), placement of vascular plugs (n = 3), a combination of both (n = 1), or a combination of coil embolization and a covered stent (n = 1). Treatment of coronary fistulae was successful in all patients with excellent post-procedural results and no follow-up death. PCI in pediatric patients with congenital heart disease can be performed safely and effectively. However, the overall 5-year survival probability of patients with CAS is reduced due to severe ischemic myocardial damage.

Mortality analysis of arterial switch operation for transposition of the great arteries with and without ventricular septal defect

OBJECTIVES

We aimed to evaluate the 90-day mortality and effect of rescue or urgent coronary revascularization in children undergoing arterial switch operation for transposition of the great arteries with and without ventricular septal defect.

METHODS

The 90-day mortality, risk factors for mortality and outcome of rescue or urgent coronary revascularization were analysed using 8 years of data from the Japan Cardiovascular Surgical Database. We only included patients with full data for all analyses.

RESULTS

A total of 1084 patients (median weight: 3.0 kg; interquartile range: 2.8-3.3) underwent arterial switch operation at a median age of 10 days (interquartile range: 7-14). The 90-day mortality (5.2%, n = 56) was ∼1.6-fold higher than 30-day mortality (3.2%, n = 35). The cause was cardiac origin in 84% of non-survivors. Fifty-nine of the 1034 patients (5.7%) required extracorporeal membrane oxygenation (ECMO), with successful weaning in 44% (n = 26). Univariable or multivariable analyses revealed the following risk factors for mortality: body weight at operation <2.5 kg, aortic cross-clamp time, cardiac events and ECMO (P < 0.005-0.001). Ventricular septal defect was not a risk factor.Thirteen patients (1.2%) had either rescue or urgent coronary revascularization with salvage rates of 25% (2/8) and 100% (5/5), respectively. Only 5 ECMO patients (8%) underwent coronary revascularization with 1 survivor.

CONCLUSIONS

The 90-day mortality represented perioperative outcomes better than 30-day mortality. Patients on ECMO, which extended the survival time, had 56% 90-day mortality. Coronary revascularization showed a salvaging effect, although the case number was small.Subj collection: 116, 137, 141.

Evaluation of Coronary Circulation after Arterial Switch Operation

BACKGROUND

Coronary artery evaluation remains after arterial switch operation a clinical challenge.

OBJECTIVE

This study aims to correlate anatomical changes diagnosed by cardiac computed tomography (CCT) with physiological alterations on clinical evaluation to diagnose coronary obstruction in late ASO patients.

METHODS

This study included 61 consecutive patients with mean age of 9.4 years who underwent ASO. The patients were submitted to echocardiography, electrocardiography, cardiopulmonary exercise test, and cardiac computed tomography to evaluate functional capacity and coronary artery anatomy.

RESULTS

Cardiac computed tomography revealed that only 3.3% of the patients had coronary stenosis. These patients were asymptomatic, and no signs of myocardial ischemia were detected by the tests.

CONCLUSION

The incidence of coronary abnormalities in late ASO patients was 3.3% in our cohort. There is no clear guideline as to why, when, and how these patients should be screened or what to propose when a coronary obstruction is diagnosed in asymptomatic patients.

Feasibility and Utility of Adenosine Stress Echocardiography in Children Following Post-Arterial Switch Operation: A Comparison with Technetium 99m-Sestamibi Myocardial Perfusion SPECT (MPS)

There is a need for a sensitive, safe, and cost-effective tool for coronary assessment among asymptomatic post-operative children who have undergone arterial switch operation (ASO) for transposition of great arteries (TGA). Adenosine stress echocardiography may be useful in assessing major structures as well for coronary functional assessment. Twenty-six children [median age 6.0 years; IQR 4.9-7.1 years, (22 boys)], who had undergone ASO at a median age of 40 days (IQR 30-75 days), were prospectively included. Left ventricular ejection fraction (LVEF) was calculated in both rest and stress studies (140 µg/kg/min of adenosine IV over 4 min), along with assessment of regional myocardial wall motion. Coronary flow reserve (CFR) was also measured in the left anterior descending artery (LAD). Technetium 99m-MIBI [0.2mCi/kg] was injected after 2 min of adenosine infusion. Adenosine infusion had to be stopped in two children, due to transient atrioventricular (AV) block. The LVEF increased from 55.87 ± 7.27 to 61.20 ± 7.70% (p  < 0.001) with adenosine stress. No significant regional wall motion abnormality was seen in rest or stress. Distal LAD could not be visualized in four patients. Basal and peak coronary flow velocities were 41.51 ± 14.12 and 74.18 ± 6.01 cm/s. Mean CFR was 1.91 ± 0.51. Myocardial perfusion scintigraphy (MPS) was normal in all the patients. Four patients were lost to follow-up and remaining children did not develop any adverse events in the follow-up period of 64.5 ± 7.19 months. Adenosine stress echocardiography is feasible as the initial screening test in the assessment of asymptomatic post-operative children with ASO, at minimal to no inconvenience to the patient. The findings concurred with stress MPS.

CT and MRI for Repaired Complex Adult Congenital Heart Diseases

An increasing number of adult congenital heart disease (ACHD) patients continue to require life-long diagnostic imaging surveillance using cardiac CT and MRI. These patients typically exhibit a large spectrum of unique anatomical and functional changes resulting from either single- or multi-stage palliation and surgical correction. Radiologists involved in the diagnostic task of monitoring treatment effects and detecting potential complications should be familiar with common cardiac CT and MRI findings observed in patients with repaired complex ACHD. This review article highlights the contemporary role of CT and MRI in three commonly encountered repaired ACHD: repaired tetralogy of Fallot, transposition of the great arteries after arterial switch operation, and functional single ventricle after Fontan operation.

Coronary artery disease in patients with congenital heart defects

The prognosis of patients with congenital heart defects has improved significantly: more and more patients reach adulthood and old age. At the same time, the possibility of cardiovascular morbidity increases. The conventional risk factors for coronary artery disease are at least as high or even higher in patients than in the general population. Obesity and sedentary life style are more common in adults with congenital heart defect (ACHD) than in general population. In some patients, for example those with coarctation of the aorta or patients with operated coronary arteries in the infancy, the incidence of coronary artery disease (CAD) is clearly increased. In some patients with cyanotic heart defects (e.g. Fontan), the incidence of CAD might be lower, but it usually returns to the average level or higher after correction of the defect. Coronary artery disease is one of the most important reasons for mortality also in ACHD patients, and the consequences of a coronary event might be more fateful in a patient with a corrected congenital heart defect than in her/his peer. There should be a paradigm shift from operative mortality and short-term outcome to long-term morbidity and prevention of cardiovascular disease - a task that often has been forgotten during follow-up visits.

State-of-the-Art Pediatric Coronary Artery Bypass Surgery: a Literature Review

Objective

To examine the results of various myocardial revascularization techniques in pediatric patients to better understand the strategies for surgical treatment of coronary artery pathologies.

Methods

We analyzed 61 publications dedicated to the indications, methods, and results of coronary bypass surgery in children. Due to the small size of this cohort, case reports are also included in our review.

Results

The main indications for coronary bypass grafting in children are Kawasaki disease, myocardial revascularization as a necessary procedure during the congenital cardiac surgery, to manage intraoperative iatrogenic damage to coronary arteries, and homozygous familial hypercholesterolemia. The use of internal thoracic arteries as conduits for coronary bypass grafting in children with Kawasaki disease showed significantly better results in long-term functionality compared to autovenous conduits (87% and 44%, respectively, P<0.001). Acute and late coronary events after arterial switch operation for the transposition of the great arteries, anomalous origin of the left coronary artery from the pulmonary artery, and left main coronary artery atresia are the main congenital heart diseases where surgical correction involves interventions on the coronary arteries.

Conclusion

The internal thoracic artery is a reliable and durable conduit that demonstrates proven growth potential in children.

EDUCATIONAL SERIES IN CONGENITAL HEART DISEASE: Echocardiographic assessment of transposition of the great arteries and congenitally corrected transposition of the great arteries

Echocardiographic assessment of patients with transposition of the great arteries and congenitally corrected transposition requires awareness of the morphology and commonly associated lesions. The pre-operative echocardiography should include a full segmental and sequential analysis. Post-operative assessment is not possible without awareness of the type of surgical procedure performed and consists of assessing surgical connections and residual lesions.

Can we predict potentially dangerous coronary patterns in patients with transposition of the great arteries after an arterial switch operation?

INTRODUCTION

Coronary artery complications are the main reason for early mortality after an arterial switch operation. Late complications are relatively rare, and there is no consensus regarding the need or indications for routine follow-up coronary artery evaluations or the best first-line assessment modality. The aim of this study was to present the long-term post-operative frequency of coronary abnormalities in asymptomatic patients with transposition of the great arteries discovered by coronary CT angiography and potential "red flags" revealed by other examinations.

PATIENTS AND METHODS

A group of 50 consecutive asymptomatic patients who underwent routine long-term coronary artery evaluation after an arterial switch operation according to our institutional protocol were qualified for this study. This routine in-hospital visit included a detailed medical interview, electrocardiography, echocardiography, Holter electrocardiography examinations, and laboratory and cardiopulmonary exercise tests. Patients who showed significant abnormalities were qualified for perfusion scintigraphy.

RESULTS

Unfavourable coronary abnormalities were detected in 30 patients (60%) and included ostial stenosis, muscular bridge, coronary fistula, interarterial course, proximal kinking, high ellipticity index, proximal acute angulation (<30 degree) of the left coronary artery, and proximal acute angulation of the right coronary artery. These features could not be predicted based on the medical interviews, surgical reports, or non-invasive screening test results.

CONCLUSION

Complex coronary configurations with potentially dangerous coronary features are common in patients with transposition after an arterial switch operation. Such high-risk patients cannot be identified indirectly, and coronary CT angiography provides accurate information that is useful for post-operative management.

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.

Functional outcomes in children with anatomically repaired transposition of the great arteries with regard to congenital ventricular septal defect and coronary pattern

OBJECTIVE

Despite decreasing mortality, functional impairments in children with transposition of the great arteries (TGA) are still a concern. This study analyses health-related physical fitness (HRPF), arterial stiffness and health-related quality of life (HRQoL) in children with anatomically repaired TGA regarding congenital ventricular septal defect (VSD) and coronary patterns.

PATIENTS AND METHODS

68 children with anatomically repaired TGA with or without VSD (12.9±3.7 years, 19.1% female) were investigated between August 2014 and October 2017. HRPF was assessed by five tests of the FITNESSGRAM, arterial stiffness was measured by oscillometric measurement using Mobil-O-Graph and HRQoL was analysed with a self-report questionnaire (KINDL-R). All test results were compared with a healthy reference cohort (n=2116, 49.1% female) adjusted for sex and age.

RESULTS

Children with anatomically repaired TGA had significantly worse HRPF (z-score: -0.58±0.81, p<0.001), increased pulse wave velocity (TGA: 4.9±0.3 m/s vs healthy: 4.8±0.3 m/s, p=0.028) and central systolic blood pressure (TGA: 105.9±5.8 mm Hg vs healthy: 103.3±5.7 mm Hg, p=0.001). No difference was found for HRQoL between the two groups (total HRQoL score: TGA: 76.5±10.2 vs healthy: 75.2±10.1, p=0.315). Neither the coronary pattern nor a congenital VSD resulted in significant differences in all functional outcomes.

CONCLUSION

Children with anatomically repaired TGA exhibit impaired HRPF and increased arterial stiffness whereas their HRQoL is normal. The underlying coronary pattern seems to have no influence on the functional outcome, nor does an accompanied congenital VSD.

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

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

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.

Large Calibre Self-Expanding Stents for Pulmonary Stenosis After the Arterial Switch, a Low-Risk Solution to a Low-Flow Situation

Branch pulmonary artery stenosis is one of the most common complications late after the arterial switch operation. The pathophysiology of stenosis in these circumstances is very different to that encountered in with normally related great vessels. The LeCompte manoeuvre leaves the pulmonary arteries straddled and stretched over the aortic root which contributing significantly to the degree of stenosis encountered. Unilateral branch pulmonary artery stenosis rarely leads to significant symptoms in young patients with biventricular repairs; however, significant discrepancies in the split flows between right and left lung may place the patient in an unfavourable physiological position as they move in to middle age. Balloon expandable stent implantation distorts the anatomical arrangement of the LeCompte and is associated with negative interactions with the often dilated aortic root. We present three cases of the use of flexible self-expanding stents to improve the physiological flow distributions to each lung whilst hopefully decreasing the risk of erosion and perforation or fistula formation related to the pulmonary artery. All three patients had uncomplicated procedures with significant improvements in vessel diameter and flow distribution noted on follow-up MRI scans. This is the first report of the use of self-expanding stents in the context of branch pulmonary artery stenosis after the LeCompte manoeuvre. Theoretically and based on our early experience, this technique provides potential safety advantages over the use of more traditional balloon expandable stents.

Usefulness of Routine Coronary CT Angiography in Patients with Transposition of the Great Arteries After an Arterial Switch Operation

Coronary complications in patients with transposition of the great arteries (TGA) after an arterial switch operation (ASO) are relatively rare, but of all the possible postoperative adverse events, they are potentially the most dangerous. The fate of the coronary arteries, which are transplanted during the neonatal ASO, remains uncertain. There is also no consensus regarding their postoperative evaluation, especially in asymptomatic patients. The aim of this study was to present the early results of routinely performed coronary computed tomography angiography (CCTA) in asymptomatic adolescents and young adults with TGA after an ASO. An initial series of 50 CCTAs performed in asymptomatic patients with TGA after an ASO were evaluated. In each case, a detailed examination of the coronary anatomy, its relationship to the surrounding structures, its exact position in the neoaortic sinus, and the presence of significant coronary abnormalities was performed. The CT scans revealed significant coronary abnormalities in 12 asymptomatic patients: three had acute proximal angulation and stenosis, four had an intra-arterial course, seven had a muscular bridge, one had a left anterior descending artery with an intramuscular course, and one had coronary fistulas to the pulmonary arteries. Additionally, in 25 patients, proximal acute angulation of at least one coronary artery was detected, and four of them had a high ellipticity index. Most of the potentially severe anatomical features were related to the left coronary artery or the left anterior descending artery. CCTA routinely performed on asymptomatic patients with TGA after an ASO provides accurate and useful information for postoperative management. The frequency of coronary anomalies and potentially dangerous anatomical features in this group of patients is high, and their impact on postoperative follow-up remains unknown.

Imaging the adult with transposition of the great arteries

PURPOSE OF REVIEW

Patients with complete and congenitally corrected transposition of the great arteries commonly survive into adulthood and present with a vast array of clinical residua.

RECENT FINDINGS

Echocardiography remains the primary imaging modality in the routine assessment of the adult with transposition of the great arteries. It provides a comprehensive anatomic and hemodynamic evaluation. Limitations to echocardiography include evaluation of the following: the systemic right ventricle, baffle patency following atrial switch procedure, coronary arteries following arterial switch procedure or Nikadoh, and multilevel right ventricular outflow tract obstruction.

SUMMARY

Each form of palliation for transposition of the great arteries results in unique long-term sequelae that affect outcomes. A multimodality approach to imaging is required for a complete evaluation.

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.