Coding of coronary arterial origin and branching in congenital heart disease: The modified Leiden Convention

Rare coronary artery variants are associated with increased mortality and reinterventions following the arterial switch operation

OBJECTIVE

To determine the influence of coronary anatomy on long-term outcomes of the arterial switch operation (ASO).

METHODS

We retrospectively reviewed patients with transposition of the great arteries or Taussig-Bing anomaly who underwent ASO at our institution between 1992 and 2022. The primary endpoint was freedom from a composite of death, transplantation, and coronary reintervention.

RESULTS

A total of 632 patients (median age, 5.0 days; interquartile range [IQR], 4.0-7.0 days) underwent ASO. Coronary anatomy included the following categories: usual (n = 411; 65%), circumflex (Cx) from sinus 2 (n = 89; 14%), inverted (n = 55; 9%), single sinus (n = 46; 7%), and intramural (n = 31; 5%). Overall operative mortality was 3% (n = 16) and highest in patients with intramural cardiac anatomy (n = 3; 10%), although it dropped to 0% in this group in the most recent decade. The median duration of follow-up was 14.5 years (IQR, 6.0-20.3 years). Twenty-year freedom from the primary endpoint was 95 ± 1% for usual anatomy, 99 ± 1% for Cx from sinus 2, 90 ± 4% for inverted, 91 ± 4% for single sinus, and 80 ± 9% for intramural (P < .001). Intramurals had the highest 20-year incidence of coronary reintervention (11 ± 8%). Cox modeling identified intraoperative coronary revision (hazard ratio [HR], 20.1; 95% confidence interval [CI], 9.4-53.9; P < .001), Taussig-Bing anomaly (HR, 4.9; 95% CI, 2.2-10.9; P < .001), and an intramural coronary artery (HR, 2.9; 95% CI, 1.0-8.2; P = .04) to be risk factors for the composite endpoint.

CONCLUSIONS

Rare coronary artery variants-particularly intramural-are associated with increased mortality and coronary reinterventions after ASO. A low threshold for unroofing intramurals is likely associated with declining mortality and improved outcomes. Additional investigations are needed to determine the long-term fate of the coronary arteries after ASO.

Coronary Artery Dimensions on Computed Tomography Following the Neonatal Arterial Switch Operation for the Complete Transposition of the Great Arteries

Coronary events are life-threatening long-term complications of the arterial switch operation for complete transposition of the great arteries. The aim of our study was to assess the dimensions of the reimplanted coronary arteries and their relationship with the various geometric characteristics to gain a better understanding of the involved mechanisms. Coronary computed tomography angiography (CCTA) scans of 78 asymptomatic pediatric patients were performed at the age of 10.7 (6.3-17.8) years. The position of the ostia, the branching angles, and the diameters of the coronary arteries were determined in a subgroup of 51 patients presenting the usual preoperative coronary anatomy. Mean Z-score of the left main coronary artery (LMCA), left anterior descending coronary artery (LAD), left circumflex coronary artery (LCX), and right coronary artery (RCA) diameters were 0.7 ± 1.2, - 0.4 ± 1.1, - 0.3 ± 1.1, and - 0.3 ± 1.1, respectively. The Z-score of the ostial LMCA diameter had a positive correlation with the remoteness from the main pulmonary artery (p < 0.001) and the branching angle (p = 0.001). The ostial diameter Z-score of the LMCA had a negative correlation with the interval between the arterial switch operation and the CCTA (p = 0.004). Even though most of the coronary diameters fell within the accepted range, which suggests normal overall development, acute branching angle and more anterior origin were associated with smaller ostial coronary artery diameter Z-scores. To prove the clinical relevance of the smaller ostial diameter of high-risk left coronary arteries and the decrease of ostial coronary artery Z-scores over time needs further follow-up studies.

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

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

Intricate MIB1-NOTCH-GATA6 Interactions in Cardiac Valvular and Septal Development

Genome-wide association studies and experimental mouse models implicate the MIB1 and GATA6 genes in congenital heart disease (CHD). Their close physical proximity and conserved synteny suggest that these two genes might be involved in analogous cardiac developmental processes. Heterozygous Gata6 loss-of-function mutations alone or humanized Mib1 mutations in a NOTCH1-sensitized genetic background cause bicuspid aortic valve (BAV) and a membranous ventricular septal defect (VSD), consistent with MIB1 and NOTCH1 functioning in the same pathway. To determine if MIB1-NOTCH and GATA6 interact in valvular and septal development, we generated compound heterozygote mice carrying different Mib1 missense (Mib1K735R and Mib1V943F) or nonsense (Mib1R530X) mutations with the Gata6STOP/+ heterozygous null mutation. Combining Mib1R530X/+ or Mib1K735R/+ with Gata6STOP/+ does not affect Gata6STOP/+ single mutant phenotypes. In contrast, combining Mib1V943F/+ with Gata6STOP/+ decreases the incidence of BAV and VSD by 50%, suggesting a suppressive effect of Mib1V943F/+ on Gata6STOP/+. Transcriptomic and functional analyses revealed that while the EMT pathway term is depleted in the Gata6STOP/+ mutant, introducing the Mib1V943F variant robustly enriches this term, consistent with the Mib1V943F/+ phenotypic suppression of Gata6STOP/+. Interestingly, combined Notch1 and Gata6 insufficiency led to a nearly fully penetrant VSD but did not affect the BAV phenotype, underscoring the complex functional relationship between MIB1, NOTCH, and GATA6 in valvular and septal development.

Left ventricular apical pacing-induced heart failure in a child after congenital heart surgery: a case report

Background

Left ventricular apical pacing (LVAP) is considered to preserve left ventricular (LV) systolic function in both patients with and without congenital heart disease. However, sporadic LVAP-associated cardiac dysfunction in children with complex structural heart disease was recently reported. We present the case of a 2.5-year-old child with complex congenital heart disease and LVAP-induced cardiomyopathy.

Case summary

Corrective surgery for double outlet right ventricle, subpulmonary ventricular septal defect, and transposition of the great arteries was done at the age of 1.5 months. Late complete atrioventricular block occurred, necessitating VVI pacemaker insertion with LV apical epicardial leads. He presented with heart failure and dilated cardiomyopathy 1.5 years after pacemaker insertion and required persistent circulatory support with intravenous inotropes. Speckle tracking echocardiography identified an important LV apical to basal dyssynchrony. After excluding any coronary artery involvement, cardiac resynchronization therapy was performed. Speckle tracking echocardiography guided lead placement resulted in improved LV contraction synchrony. Cardiac function recovered progressively in combination with oral heart failure medication and is almost normal at 10-month follow-up.

Discussion

Right ventricular pacing is a well-known cause of pacing-induced cardiomyopathy. The LV apex and LV free wall are thought to be most optimal locations for ventricular pacing in children. However, LVAP can also be the cause of a pacing-induced cardiomyopathy and decreased systolic LV function in children with complex congenital heart disease due to lack of LV contraction synchrony. Cardiac resynchronization therapy can reverse this LV dysfunction and remodelling.

Coronary coding in dTGA pre- and post-ASO-verification and necessary corrections following adult CMR

Aims

In adult patients with transposition of the great arteries (dTGA) after arterial switch operation (ASO), the coronary artery circulation after neonatal surgical transfer remains a major culprit for long-term sequelae, including myocardial ischaemia and sudden cardiac death. As coronary imaging in paediatric age is often incomplete and classification mainly relies on the surgeon's description in the operation report, we intended to develop a systematic, understandable pattern of the coronary status for each young patient, combining unambiguous coding with non-invasive imaging.

Methods and results

The monocentric prospective study evaluated 89 young adults (mean 23 years) after ASO for dTGA including cardiac magnetic resonance (CMR) coronary angiography. Following 'The Leiden Convention coronary coding system', we describe the systematic transformation process and provide a graphical illustration considering surgical and imaging views for the six main coronary types, followed by a comparison with adult CMR. Discordance between surgeon's and CMR classification is evaluated.In seven (7.9%) patients, a discordance between the surgeon's post-operative and the CMR classification was found; therefore, the initial classification had to be corrected according to adult CMR. Three cases (3.4%) with particularly challenging coronary variants (intramural and interarterial course, functional common ostium) are presented.

Conclusion

Considering the risks of a possible neonatal coronary misclassification and of increasing additional acquired coronary artery disease with age, reliable cooperation between surgeons, cardiologists, and imaging specialists must be ensured. Therefore, after completion of growth, a systematic pattern of the coronary artery status, combining unambiguous coding with CMR imaging, should be established for each patient.

Late follow-up of neo-aortic dimensions and coronary arteries in adult patients after the arterial switch operation

Background

After the arterial switch operation (ASO) for transposition of the great arteries (TGA), neo-aortic dilatation and coronary arterial anomalies, especially an interarterial course and acute coronary artery take-off angle, are commonly found. Long-term follow-up data after ASO is scarce. Aim of this study was to determine the prevalence of neo-aortic dilatation and coronary abnormalities, with special emphasis on acute coronary take-off angle, in adult TGA-ASO patients.

Methods

In this retrospective cohort study, all adult TGA-ASO patients with ≥1 CT-angiography (CTA) at the age of ≥16 years were included.

Results

Eighty-one patients, 69 % male and median age 21.0 [18.5-22.8] years, were included. At baseline, maximum neo-aortic diameter was 39.2 ± 5.3 mm; 35 (43 %) patients had neo-aortic dilatation (neo-aortic diameter of >40 mm), 22 (27 %) patients had an acute coronary take-off angle (<30°), and 5 (6 %) patients had an interarterial course of the RCA (2 %) or LCA (4 %). Neo-aortic or coronary artery re-intervention occurred in 10 (12 %) patients. All 10 patients had neo-aortic dilatation or coronary take-off angle of <30° on baseline CTA.

Conclusion

This study reports a prevalence of 43 % of neo-aortic dilatation, 6 % of interarterial coronary course and 27 % for acute coronary take-off angle (<30°) at a median term of 21.0 years post ASO. All patients with a neo-aortic re-intervention or coronary artery re-intervention during follow-up had a maximum neo-aortic diameter of >40 mm or a coronary take-off angle of <30° at baseline CTA. This hypothesis generating study suggests that an active surveillance in patients with neo-aortic dilation and/or an acute angulation of < 30° post ASO might be considered and requires prospective evaluation.

Clinical effects of major aortopulmonary collateral arteries in term neonates diagnosed with transposition of the great arteries

BACKGROUND

Transposition of the great arteries is a severe CHD that affects term neonates. The presence of major aortopulmonary collateral arteries in neonatal transposition of the great arteries patients is rare. This study investigated the clinical and haemodynamic implications of the presence of major aortopulmonary collateral arteries in neonatal transposition of the great arteries patients who underwent an arterial switch operation.

MATERIALS AND METHODS

The study was a retrospective analysis conducted on neonates diagnosed with transposition of the great arteries who underwent arterial switch operation within the period from 1 May 2020 to 1 January 2023 at two high-patient-volume paediatric cardiac surgery centres in Turkey. The patients' demographic characteristics, echocardiographic features, and clinical data were analysed. Additionally, the possible clinical effects of the presence of major aortopulmonary collateral arteries were statistically evaluated.

RESULTS

Two hundred cases of neonatal transposition of the great arteries were included in this study, with 55% of the cases male. All the patients underwent arterial switch operation. The median age at the time of arterial switch operation was 5 days (interquartile range 3-7), with a median weight of 3,100 g (interquartile range 2,900-3,400). The median pre-operative saturation level was 76% (interquartile range 70-82%). Prior to arterial switch operation, 32 patients underwent balloon atrial septostomy.In all the patients, the interatrial septum was checked to determine if the atrial septum was intact. A patent foramen ovale (≤ 3 mm) was found in 112 patients, and a non-restrictive atrial septal defect (> 3 mm) was found in 88. Forty-eight patients had ventricular septal defects, and 72 had coronary anomalies. Major aortopulmonary collateral arteries were found in 4 patients pre-operatively and in 12 patients after arterial switch operation (echocardiography, n = 8; angiography, n = 4). Of the patients with post-operative detection of cumulative number of major aortopulmonary collateral arteries were on post-operative day 1 in 2 patients, on post-operative day 3 in 5 patients, on post-operative day 7 in 6 patients, and on post-operative day 14 in 11 patients.Transcatheter closure was performed in 3 cases due to recurrent extubation failure. Major aortopulmonary collateral artery shrinkage was observed in one case under medical treatment. The length of paediatric cardiac intensive care unit stay (10 days versus 8 days; p < 0.005), mechanical ventilator time (4 days versus 2 days; p = 0.02), and inotrope use time (5 days versus 3 days; p = 0.04) were higher in the major aortopulmonary collateral artery cases than patients without major aortopulmonary collateral artery.

CONCLUSION

Major aortopulmonary collateral arteries are frequent in transposition of the great arteries patients and may have clinical effects. The presence of major aortopulmonary collateral arteries should be investigated in patients who do not have a favourable post-operative course after arterial switch operation.

Transection and reimplantation of anomalous right coronary artery from single left coronary artery in a collegiate athlete

Coronary artery anomalies may induce myocardial ischaemia and sudden cardiac death when associated with areas of compression or stenosis. We present a case of transection and reimplantation of an anomalous interarterial right coronary artery arising from a single left main coronary artery. The 18-year-old collegiate athlete had exertional chest pain and haemodynamically significant compromise to coronary blood flow.

Coronary artery disease in adults with congenital heart disease

The increasing population of adult patients with congenital heart disease (ACHD) is at risk of developing coronary artery disease (CAD) and other atherosclerotic cardiovascular diseases due to exposure to cardiovascular risk factors. The impact of this exposure is growing larger as life expectancy of these subjects increases with the progressive improvement in management of congenital heart disease. Studies have shown that ACHD patients have a higher risk for CAD than their non-ACHD matches, highlighting the need for awareness and prevention efforts among congenital heart disease specialists and non-ACHD cardiologists. At the same time, ACHD patients with CAD often present specific characteristics all practicing cardiologists should be aware of. While further research is needed to fully understand the mechanisms underlying the higher CAD risk in this population, this article summarizes key evidence on CAD in ACHD and emphasizes on one hand the importance of early screening and management of known cardiovascular risk factors in ACHD patients, particularly those who are younger, female, or have more complex/severe CHD. On the other hand, it calls for a broader knowledge of ACHD risk for CAD and its peculiarities among all cardiologists.

Decision making in anomalous aortic origin of a coronary artery

INTRODUCTION

There are many uncertainties surrounding anomalous aortic origin of a coronary artery (AAOCA) including the pathophysiology of sudden cardiac death, how to best risk stratify patients, how to best evaluate patients, who would benefit from exercise restriction, who should undergo surgical intervention, and which operation to perform.

AREAS COVERED

The goal of this review is to provide a comprehensive but succinct overview of AAOCA to help clinicians with the difficult task of navigating optimal evaluation and treatment of an individual patient with AAOCA.

EXPERT OPINION

Beginning in year 2012, some of our authors proposed an integrated, multi-disciplinary working group which has become the standard management strategy for patients diagnosed with AAOCA. A multi-disciplinary team with a focus on shared decision-making with the patients/families is likely necessary to optimize outcomes. Long-term follow-up and research are needed to improve our understanding of AAOCA.

Successful Management of a Very Unusual Coronary Pattern in Transposition of the Great Arteries

Coronary artery anatomy is the key to a successful arterial switch operation in transposition of the great arteries. We came across an unusual coronary pattern in a child with transposition in which the three major coronary arteries were seen arising from all three aortic sinuses. This coronary pattern is the first of its kind in transposition, and this case report emphasizes the difficulty in translocating such a rare coronary pattern while performing an arterial switch operation.

Anomalous connection of the circumflex coronary artery to the pulmonary trunk in a patient with Taussig–Bing anomaly: a case report

Background

Coronary anomalies are present in one-third of all patients with transposition of the great arteries (TGA) and have been associated with increased risk of adverse outcomes after the arterial switch operation. Therefore, knowledge about coronary anatomy remains key.

Case summary

A 5-day-old girl with prenatal diagnosis of Taussig–Bing anomaly (double outlet right ventricle with TGA and large subpulmonary ventricular septal defect) along with aortic arch hypoplasia and coarctation of the aorta underwent the arterial switch operation with closure of the ventricular septal defect and aortic arch repair. On preoperative echocardiography, the right (R) and left coronary artery (LCx) connected both to aortic sinus 1, suggesting 1RLCx coronary anatomy according to the Leiden Convention coronary coding system. However, intraoperative inspection led to a reclassification of the coronary anatomy: the right coronary artery and left anterior descending coronary artery connected to aortic sinus 1 (1RL) as had been observed on echocardiography, but—remarkably—the circumflex coronary artery (Cx) connected to the posterior sinus of the pulmonary trunk. As a consequence, cardioplegia was administered into both the aortic and pulmonary roots, and the circumflex coronary artery could stay in its native position without having to be transferred during the arterial switch operation.

Discussion

Various disruptions during embryological development can lead to unusual coronary anatomy in TGA patients. While anomalous connection of a coronary artery to the pulmonary trunk remains exceedingly rare, care should be taken to identify this pattern when present as failure to do so may result in adverse outcomes.

Techniques and pitfalls of coronary arterial reimplantation in anatomical correction of transposition

BACKGROUND AND AIM

We assessed the anatomical variations in coronary arterial patterns relative to the techniques of reimplantation in the setting of the arterial switch operation, relating the variations to influences on outcomes.

METHODS

We reviewed pertinent published investigations, assessing events reported following varied surgical techniques for reimplantation of the coronary arteries in the setting of the arterial switch procedure.

RESULTS

The prevalence of reported adverse events, subsequent to reimplantation, varied from 2% to 11%, with a bimodal presentation of high early and low late incidence. The intramural pattern continues to contribute to mortality, with some reports of 28% fatality. The presence of abnormal course relative to the arterial pedicles in the setting of single sinus origin was associated with a three-fold increase in mortality. Abnormal looping with bisinusal origin of arteries was not associated with increased risk.

CONCLUSION

The techniques of transfer of the coronary arteries can be individually adapted to cater for the anatomical variations. Cardiac surgeons, therefore, need to be familiar with the myriad creative options available to achieve successful repair when there is challenging anatomy. Long-term follow-up will be required to affirm the superiority of any specific individual technique. Detailed multiplanar computed-tomographic scanning can now reveal all the variants, and elucidate the mechanisms of late complications. Coronary angioplasty or surgical revascularization may be considered in selected cases subsequent to the switch procedure.

A comprehensive analysis of the intramural segment in interarterial anomalous coronary arteries using computed tomography angiography

Aims

An anomalous coronary artery originating from the opposite sinus of Valsalva (ACAOS) with an interarterial course can be assessed using computed tomography angiography (CTA) for the presence of high-risk characteristics associated with sudden cardiac death. These features include a slit-like ostium, acute angle take-off, proximal luminal narrowing, and an intramural segment. To date, no robust CTA criteria exist to determine the presence of an intramural segment. We aimed to deduct new CTA parameters to distinguish an intramural course of interarterial ACAOS.

Methods and results

Twenty-five patients with an interarterial ACAOS (64% female, mean age 46 years, 88% right ACAOS) from two academic hospitals were evaluated. Inclusion criteria were the availability of a preoperative CTA scan (0.51 mm slice thickness) and peroperative confirmation of the intramural segment. Using multiplanar reconstruction of the CTA, the distance between the lumen of the aorta and the lumen of the ACAOS [defined as ‘interluminal space’ (ILS)] was assessed at 2 mm intervals along the intramural segment. Analysis showed a mean ILS of 0.69 ± 0.15 mm at 2 mm from the ostium. At the end of the intramural segment where the ACAOS becomes non-intramural, the mean ILS was significantly larger (1.27 ± 0.29 mm, P &lt; 0.001). Interobserver agreement evaluation showed good reproducibility (intraclass correlation coefficient 0.77, P &lt; 0.001). Receiver operator characteristic analysis demonstrated that at a cut-off ILS of &lt;0.95 mm, an intramural segment can be diagnosed with 100% sensitivity and 84% specificity.

Conclusion

The ILS is introduced as a novel and robust CTA parameter to identify an intramural course of interarterial ACAOS. An ILS of &lt;0.95 mm is indicative of an intramural segment.

Impact of Coronary Artery Anatomy in Arterial Switch Operation: In-hospital and Post-discharge Outcomes

OBJECTIVE

The influence of the coronary artery anatomy on the prognosis of patients receiving an arterial switch operation (ASO) is currently controversial, and the risk factors for this operation may change in more complicated patients. This study aimed to investigate the influence of coronary artery anomalies on the in-hospital and post-discharge outcomes of ASO in patients with transposition of the great arteries (TGA) and Taussig-Bing anomaly (TBA).

METHODS

We retrospectively reviewed 206 patients who underwent ASO from January 2007 to December 2019. The median age at operation was 33 [interquartile range (IQR): 20-71] days. Median follow-up time was 7.2 years (IQR: 4.0-10.3 years).

RESULTS

Coronary anomalies were present in 86 patients (41.7%), with 9 (4.4%) of them having a single coronary artery. Additional coronary features included intramural courses in 5 (2.4%) patients, ostial stenosis in 1 (0.5%) patient, and accessory coronary artery orifices in 5 (2.4%) patients. There were 32 (15.5%) in-hospital deaths and 8 (4.6%) post-discharge deaths, yielding an overall survival of 81.3%, 80.7% and 79.9% at 1, 5 and 10 years, respectively. Mortality due to ASO has been drastically decreased since 2013. Patients with a single coronary artery had higher rate of in-hospital mortality, but this finding was not statistically significant. The earlier surgical era (OR: 2.756) and a longer cardiopulmonary bypass time (OR: 2.336) were significantly associated with in-hospital mortality, while coronary patterns were not. An intramural coronary artery (HR: 10.034) and a patient age of older than 1 year at the time of ASO (HR: 9.706) were independent predictors of post-discharge mortality.

CONCLUSION

ASO remains the procedure of choice for TGA with coronary anomalies with acceptable in-hospital and post-discharge outcomes in terms of overall survival and freedom of reoperation. However, intramural coronary artery is an independent risk factor for post-discharge mortality. Timely surgery within the 1st year of life helps improve overall midterm survival of ASO.

Introduction to Special Issue “Leaders in Cardiovascular Research, Dedicated to the Memory of Professor Adriana Gittenberger-de Groot”

This Introduction provides both a short reflection on the scientific career of Adriana Gittenberger-de Groot and an overview of the papers that form the basis of this Special Issue giving them a proper perspective. The papers have as a central focus the outflow tract, and include contributions on development and pathology of the ventricles including AV valves, as well as developmental and pathomorphological aspects of the great arteries including semilunar valves and coronary arteries.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Leiden Convention coronary coding system: translation from the surgical to the universal view

AIMS

The Leiden Convention coronary coding system structures the large variety of coronary anatomical patterns; isolated and in congenital heart disease. It is widely used by surgeons but not by cardiologists as the system uses a surgeons' cranial view. Since thoracic surgeons and cardiologists work closely together, a coronary coding system practical for both disciplines is mandatory. To this purpose, the 'surgical' coronary coding system was adapted to an 'imaging' system, extending its applicability to different cardiac imaging techniques.

METHODS AND RESULTS

The physician takes place in the non-facing sinus of the aortic valve, oriented with the back towards the pulmonary valve, looking outward from the sinus. From this position, the right-hand sinus is sinus 1, and the left-hand sinus is sinus 2. Next, a clockwise rotation is adopted starting at sinus 1 and the encountered coronary branches described. Annotation of the normal anatomical pattern is 1R-2LCx, corresponding to the 'surgical' coding system. The 'imaging' coding system was made applicable for Computed Tomography (CT), Magnetic Resonance Imaging (MRI), echocardiography, and coronary angiography, thus facilitating interdisciplinary use. To assess applicability in daily clinical practice, images from different imaging modalities were annotated by cardiologists and cardiology residents and results scored. The average score upon evaluation was 87.5%, with the highest scores for CT and MRI images (average 90%).

CONCLUSION

The imaging Leiden Convention is a coronary coding system that unifies the annotation of coronary anatomy for thoracic surgeons, cardiologists, and radiologists. Validation of the coding system shows it can be easily and reliably applied in clinical practice.

Deep Phenotypic Analysis for Transposition of the Great Arteries and Prognosis Implication

Background

Transposition of the great arteries (TGA) consists of about 3% of all congenital heart diseases and 20% of cyanotic congenital heart diseases. It is always accompanied by a series of other cardiac malformations that affect the surgical intervention strategy as well as prognosis. In this study, we comprehensively analyzed the phenotypes of the patients who had TGA with concordant atrioventricular and discordant ventriculoarterial connections and explored their association with prognosis.

Methods and Results

We retrospectively reviewed 666 patients with a diagnosis of TGA with concordant atrioventricular and discordant ventriculoarterial connections in Fuwai Hospital from 1997 to 2019. Under the guidance of the Human Phenotype Ontology database, patients were classified into 3 clusters. The Kaplan‐Meier method was used to analyze the prognosis, and the Cox proportional regression model was used to investigate the risk factors. In this 666‐patient TGA cohort, the overall 5‐year survival rate was 94.70% (92.95%–96.49%). Three clusters with distinct phenotypes were obtained by the Human Phenotype Ontology database. Kaplan‐Meier analysis revealed a significant difference in freedom from reintervention among 3 clusters (P<0.001). To eliminate the effect of surgeries, we analyzed patients who only received an arterial switch operation and still found a significant difference in reintervention (P=0.019).

Conclusions

We delineated a big cardiovascular phenotypic profile of an unprecedentedly large TGA cohort and successfully risk stratified them to reveal prognostic significance. Also, we reported the outcomes of a large TGA population in China.

Early and Late Outcomes after Arterial Switch Operation: A 40-Year Journey in a Single Low Case Volume Center

Background and Objectives: The results of the arterial switch operation in large congenital heart centers are excellent, and the results in small and medium centers are improving. The objective of this article is to share our experience utilizing the international knowledge transfer program to improve early and late arterial switch operation outcomes in our center. Materials and Methods: A retrospective analysis of patients who underwent the arterial switch operation in Vilnius University Santaros Clinics Cardiothoracic Surgery Center between 1977–2020 was performed. Results: A total of 127 consecutive arterial switch operations were performed in our center. Surgical mortality during the entire study period was 24.6%. Surgical mortality prior to the program, during the program, and after the program was 88.24%, 41.7%, and 5.81%, respectively (p < 0.0001). The surgical mortality of patients operated on during the last 10 years was 4%. The overall survival estimate for the 97 surviving patients was 96.9%, 94.9%, 93.8%, 93.8%, 93.8%, 93.8% at 1, 3, 5, 10, 15, and 20 years, respectively. Risk factors for early mortality included longer aortic cross-clamp time and operation prior to the knowledge transfer program. The only significant risk factor for late reintervention was concomitant aortic arch obstruction treated at the time of the arterial switch. Conclusions: The surgical treatment of transposition of the great arteries by means of an arterial switch with good results can be possible in low-to-medium volume congenital heart surgery centers. International knowledge transfer programs between high-expertise high-volume congenital heart centers and low-to-medium volume congenital heart centers may help to shorten the learning curve and improve early and late outcomes after an arterial switch. The risk factors for surgical mortality and intervention-free survival in low-volume surgical centers are similar to those in high-volume centers. Late arterial switch-related complications are similar to those among different-sized congenital heart centers.

Ventricular and atrial function and deformation is largely preserved after arterial switch operation

OBJECTIVE

To test the hypothesis that ventricular and atrial function are different between patients with transposition of the great arteries (TGA) after arterial switch operation (ASO) and healthy controls.

METHODS

103 consecutive patients with TGA (median age: 16.7 years, 4.3-39.6 years, 71.8% male) were compared with 77 controls (median age: 15.4 years, 6.3-43.2 years, 66.2% male). Biventricular and biatrial function were assessed using standard cardiovascular magnetic resonance (CMR) techniques and feature tracking. Group comparison was performed with conventional non-parametrical statistics and machine learning methods to find the variables most discriminative between patients and controls. These variables were used to build a multivariable logistic regression model to assess the case-control status.

RESULTS

Markers of left and right ventricular function (LV; RV) (ejection fraction, MAPSE, TAPSE, LV long-axis strain) as well as LV global longitudinal (-20.7 (-24.1; -17.9) vs -23.7 (-26.1; -21.6), p<0.001), circumferential (-29.4 (-32.2; -26.5) vs -30.5 (-33.6; 29), p=0.001) and atrial longitudinal strain (left atrium (LA): 23.3 (18.6; 28.8) vs 36.7 (30.7; 44), p<0001; right atrium: 21.7 (18.2; 27.8) vs 34.9 (26.9; 40.3), p<0.001) were reduced in patients compared with controls using non-parametrical testing. The logistic regression model including the most discriminative variables from univariate and machine learning analysis demonstrated significant differences between patients and controls only for TAPSE and LA global longitudinal strain.

CONCLUSIONS

Biventricular and biatrial function are largely preserved after ASO for TGA. Using a comprehensive CMR protocol along with statistical machine learning methods and a regression approach, only RV longitudinal function and LA function are significantly impaired.

Applicability of the Leiden Convention and the Lipton Classification in Patients with a Single Coronary Artery in the Setting of Congenital Heart Disease

In single coronary artery (SCA) anatomy, all coronary tributaries arise from a single ostium, providing perfusion to the entire myocardium. Coronary classification systems can facilitate the description of SCA anatomy. Aim: Evaluation of the applicability of Lipton classification and the Leiden Convention coronary coding system in SCA. Methods: All patients (n = 6209) who underwent computed tomography (CT) scanning between 2014 and 2018 were retrospectively examined for the presence of SCA and classified, according to Lipton classification and the Leiden Convention coronary coding system. Results: The prevalence of SCA was 0.51% (32/6209). Twenty-eight patients (87.5%) had coexisting congenital heart disease (CHD), most frequently pulmonary atresia (9/32, 28.1%). Ten patients (10/32, 31.25%) could not be classified with either the Leiden Convention or Lipton classification (pulmonary atresia n = 9, common arterial trunk (CAT) n = 1). In one case with CAT, Lipton classification, but not the Leiden Convention, could be applied. In two cases with the transposition of the great arteries and in two cases of double outlet right ventricle, the Leiden Convention, but not the Lipton classification, could be applied. Conclusions: Both classifications are useful to detail information about SCA. As Lipton classification was not developed for structural heart disease cases, in complex CHD with abnormal position of the great arteries, the Leiden Convention is better applicable. The use of both systems is limited in pulmonary atresia. In this scenario, it is better to provide a precise description of the coronary origin and associated characteristics that might affect treatment and prognosis.

Long-Term Survival and Freedom From Coronary Artery Reintervention After Arterial Switch Operation for Transposition of the Great Arteries: A Population-Based Nationwide Study

Background The aim of this study was to evaluate long-term survival and freedom from coronary artery reintervention after the arterial switch operation (ASO). Methods and Results This single-center nationwide retrospective study included consecutive children who underwent ASO between 1990 and 2016 (n=605). Long-term outcomes were obtained by cross-mapping individual data with the National Death Registry and the National Registry of Cardiovascular Interventions for adults. A control group was randomly retrieved at a 1:10 ratio from the National Birth and Death Registries. Early mortality was 3.3% and late mortality was 1.7% during a median follow-up of 10 (interquartile range, 5-16) years. The probability of overall survival at 20 years after ASO was 94.9% compared with 99.5% in the background population (hazard ratio [HR] 15.6; 95% CI, 8.9-27.5, P<0.001). Independent multivariable predictors of worse survival were an intramural coronary artery (HR, 5.2; 95% CI, 1.8-15.2, P=0.002) and period of ASO 1990 to 1999 (HR, 4.6; 95% CI, 1.5-13.6, P<0.001). Fourteen patients (2.3%) required 16 coronary artery reoperations. Freedom from coronary artery reintervention at 20 years after ASO was 96%. The only independent multivariable predictor associated with a higher hazard for coronary artery reintervention was an intramural coronary artery (HR, 33.9; 95% CI, 11.8-97.5, P<0.001). Conclusions Long-term survival after ASO is excellent. Coronary artery reinterventions are rare. An intramural coronary artery was an independent predictor associated with a higher risk for coronary artery reintervention and death, regardless of the surgical period.

Tetra ostial coronary arterial anatomy-A rare pattern in transposition

BACKGROUND

Meticulous transfer of coronary arteries is of crucial importance in transposition and determines the success of the switch procedure. This report describes a coronary arterial anatomy consisting of four separate ostia from the two facing sinuses in a 6-month-old infant presenting with transposition and ventricular septal defect.

CONCLUSION

Being a rare coronary arterial pattern not described in previous coding systems, the surgeon would do well to be aware of this possibility while performing the switch procedure.

Coronary Anatomy in Congenital Heart Disease: The Important Contributions of Professor Dr. Adriana Gittenberger-de Groot

The contributions of Professor Dr. Adriana Gittenberger-de Groot in relation to coronary artery development and classification are described from the viewpoint of a pediatric cardiac surgeon.

The first multicentre study on coronary anomalies in the Netherlands: MuSCAT

Background

Current guidelines on coronary anomalies are primarily based on expert consensus and a limited number of trials. A gold standard for diagnosis and a consensus on the treatment strategy in this patient group are lacking, especially for patients with an anomalous origin of a coronary artery from the opposite sinus of Valsalva (ACAOS) with an interarterial course.

Aim

To provide evidence-substantiated recommendations for diagnostic work-up, treatment and follow-up of patients with anomalous coronary arteries.

Methods

A clinical care pathway for patients with ACAOS was established by six Dutch centres. Prospectively included patients undergo work-up according to protocol using computed tomography (CT) angiography, ischaemia detection, echocardiography and coronary angiography with intracoronary measurements to assess anatomical and physiological characteristics of the ACAOS. Surgical and functional follow-up results are evaluated by CT angiography, ischaemia detection and a quality-of-life questionnaire. Patient inclusion for the first multicentre study on coronary anomalies in the Netherlands started in 2020 and will continue for at least 3 years with a minimum of 2 years of follow-up. For patients with a right or left coronary artery originating from the pulmonary artery and coronary arteriovenous fistulas a registry is maintained.

Results

Primary outcomes are: (cardiac) death, myocardial ischaemia attributable to the ACAOS, re-intervention after surgery and intervention after initially conservative treatment. The influence of work-up examinations on treatment choice is also evaluated.

Conclusions

Structural evidence for the appropriate management of patients with coronary anomalies, especially (interarterial) ACAOS, is lacking. By means of a structured care pathway in a multicentre setting, we aim to provide an evidence-based strategy for the diagnostic evaluation and treatment of this patient group.

Supplementary Information

The online version of this article (10.1007/s12471-021-01556-9) contains supplementary material, which is available to authorized users.

The Incorporation of Hands-On Surgical Training in a Congenital Heart Surgery Training Curriculum

BACKGROUND

The monthly in-house Hands-On Surgical Training (HOST) program was incorporated into the congenital heart surgery (CHS) curriculum for surgical trainees within our institution. This study evaluated whether there was an improvement and retention of technical skills throughout the curriculum via objective assessment methods.

METHODS

Twelve 3-dimensional-printed surgical heart models were included into the year-long curriculum. The monthly sessions were attended by all trainees and staff surgeons. Proctors demonstrated the operation on a model, which was followed by 2 attempts by each trainee. Attempts were recorded for objective assessment. On completion of the curriculum trainees repeated 4 procedures an additional 2 times after a delay to assess skill retention.

RESULTS

Twelve sessions were completed by 7 trainees within the curriculum. Objective assessments were performed in 7 sessions. Eighty-one percent of trainees' scores improved between the 2 attempts, with a mean improvement of 13% (attempt 1: HOST-CHS score of 79, attempt 2: HOST-CHS score of 89; P < .001). Similarly, 91% of procedural times improved by a mean of 25% (attempt 1, 1:22:00 [hours:minutes:seconds]; attempt 2, 1:01:21; P < .001). During individual procedure analysis, statistical significance remained in 3 of 7 procedures (P < .05). Four procedures were assessed for skill retention after a delay (2-14 months). Scores decreased by 4% in 47% of trainees during attempt 3 (attempt 2: HOST-CHS score of 94, attempt 3: HOST-CHS score of 91; P = .34) but improved in 79% during attempt 4 (attempt 3: HOST-CHS score of 91, attempt 4: HOST-CHS score of 99; P = .004), matching their previous performance.

CONCLUSIONS

The monthly HOST course was successfully incorporated into a training curriculum for CHS surgeons using objective assessments to measure technical performance. Trainees demonstrated an improvement across all evaluated procedures and retained their skills when reassessed after a delay highlighting its value in CHS training.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Prevalence and Anatomic Characteristics of Single Coronary Artery Diagnosed by Computed Tomography Angiography

Single coronary artery (SCA) is a rare congenital anomaly. We assessed the prevalence and anatomic characteristics of SCA diagnosed with coronary computed tomography angiography and compared the dimensions of the proximal SCA trunk with a reference group of 199 subjects with normal coronary arteries. We screened 30,230 patients who underwent coronary computed tomography angiography from 2008 to 2018 to identify 17 with SCA (age 55 ± 19.0 years, 8 men [47%]). The prevalence of SCA was 0.056%. SCA originated from the right sinus of Valsalva in 11 patients (65%) and from the left sinus of Valsalva in 6 subjects. According to Lipton's classification, the 17 SCAs were L1 (n = 5, 29%), L2-A (n = 1, 6%), R2-A (n = 2, 12%), R2-B (n = 6, 35%), R2-P (n = 2, 12%), and R3 (n = 1, 6%). (Lipton's classification consists of 3 groups and the division is based on the site of origin of SCA ["R" - right, "L" - left sinus of Valsalva] and its anatomical course relating to the ascending aorta and pulmonary trunk ["A" - anterior to the pulmonary trunk, "B" - between the aorta and pulmonary trunk, "P" - posterior to the aorta].) As compared with the reference group, SCA patients had shorter proximal trunks (5.0 ± 3.6 mm vs 8.6 ± 4.8 mm, p = 0.0012). The lumen area (LA) and lumen diameter of the proximal trunk in patients with SCA were larger than the LA and lumen diameter of the left main coronary artery from the reference group (49.5 ± 18.0 mm2 vs 21.3 ± 6.5 mm2, p <0.0001, and 7.8 ± 1.6 mm vs 5.1 ± 0.75 mm, p <0.0001, respectively). Moreover, the LA of the proximal SCA trunk was larger than the sum of respective measurement performed in left main coronary artery and proximal right coronary artery segments in the control group (49.5 ± 18.0 mm2 vs 34.0 ± 7.9mm2, p = 0.0001). In conclusion, the incidence of SCA is very low; but this condition is associated with significant enlargement of the proximal vessel segment.

Transposition With Unobstructed Right Aortic Arch and Bicuspid Aortic Valve

In patients with transposition, a right aortic arch has rarely been reported among the associated malformations. When present, the arch has been obstructed because of the presence of aortic coarctation and/or arch hypoplasia. A bicuspid aortic valve is also very rare in the presence of transposition. We report here the unusual association of transposition, an unobstructed right aortic arch, and a bicuspid aortic valve in a neonate who underwent a successful arterial switch operation.

Development and evolution of the metazoan heart

The mechanisms of the evolution and development of the heart in metazoans are highlighted, starting with the evolutionary origin of the contractile cell, supposedly the precursor of cardiomyocytes. The last eukaryotic common ancestor is likely a combination of several cellular organisms containing their specific metabolic pathways and genetic signaling networks. During evolution, these tool kits diversified. Shared parts of these conserved tool kits act in the development and functioning of pumping hearts and open or closed circulations in such diverse species as arthropods, mollusks, and chordates. The genetic tool kits became more complex by gene duplications, addition of epigenetic modifications, influence of environmental factors, incorporation of viral genomes, cardiac changes necessitated by air‐breathing, and many others. We evaluate mechanisms involved in mollusks in the formation of three separate hearts and in arthropods in the formation of a tubular heart. A tubular heart is also present in embryonic stages of chordates, providing the septated four‐chambered heart, in birds and mammals passing through stages with first and second heart fields. The four‐chambered heart permits the formation of high‐pressure systemic and low‐pressure pulmonary circulation in birds and mammals, allowing for high metabolic rates and maintenance of body temperature. Crocodiles also have a (nearly) separated circulation, but their resting temperature conforms with the environment. We argue that endothermic ancestors lost the capacity to elevate their body temperature during evolution, resulting in ectothermic modern crocodilians. Finally, a clinically relevant paragraph reviews the occurrence of congenital cardiac malformations in humans as derailments of signaling pathways during embryonic development.

The cardiac regulatory toolkit contains many factors including epigenetic, genetic, viral, hemodynamic, and environmental factors, but also transcriptional activators, repressors, duplicated genes, redundancies and dose‐dependancies.

Numerous toolkits regulate mechanisms including cell‐cell interactions, EMT, mitosis patterns, cell migration and differentiation and left/right sidedness involved in the development of endocardial cushions, looping, septum complexes, pharyngeal arch arteries, chamber and valve formation and conduction system.

Evolutionary development of the yolk sac circulation likely preceded the advent of endothermy in amniotes.

Parallel evolutionary traits regulate the development of contractile pumps in various taxa often in conjunction with the gut, lungs and excretory organs.

Embryology of coronary arteries and anatomy/pathophysiology of coronary anomalies. A comprehensive update

OBJECTIVES

This paper reviews new findings in both embryology of coronary arteries and in clinical observations of coronary artery anomalies.

FOCUS

Our presentation emphasizes studies based on: 1) newer methods of coronary development in animals and humans, and 2) intravascular ultrasonography to interpret pathophysiology and guide treatment of coronary anomalies.

CONCLUSIONS

New data reveal the roles of many cellular interactions and signaling pathways involved in the normal and abnormal formation of the coronary arterial system and the consequences of their defective formation. Pathogenetic developmental mechanisms include dysfunction of the Notch and Hypo signaling pathways, angiogenic and arteriogenic molecules, and neural crest cells. We addressed numerous clinically significant coronary anomalies and their prevalence in a general population (especially those characterized by an ectopic origin with aortic intramural course), and point out the critical relevance of understanding the variable mechanisms of coronary dysfunction, especially, fixed versus phasic stenoses or intermittent spasm, and individual severity of clinical presentations.