D-transposition of the great arteries: the current era of the arterial switch operation

How reliably does prenatal echocardiography predict urgent balloon atrial septostomy in fetuses with d-TGA?

OBJECTIVE

To analyze the prenatal and postnatal outcomes of fetuses with d-TGA and to determine whether prenatal echocardiography may predict postnatal urgent BAS.

STUDY DESIGN

A retrospective study of fetuses with d-TGA, for which fetal echocardiography was performed at our tertiary hospital from January 2018 to May 2023. We assessed the appearance of the septum primum and the FO flap in the four-chamber view as to whether the FO had a restrictive appearance during measurement of the diameter of the FO at its maximal angle to the attachment point. Color Doppler was used to detect VSDs and measure its diameter both in the four-chamber view and when visualizing the outlets of the great arteries in the sagittal section of the heart.

RESULTS

During the study period, 64 fetuses were diagnosed with d-TGA, which was also confirmed postnatally. Of these, 16 fetuses were excluded due to additional cardiac anomalies or the inability to reach the mother. In total, 48 cases were included in this series. In our study, the FO diameter was significantly decreased in the urgent BAS group, compared with the fetuses without urgent BAS (5.1 mm vs 6.3 mm). A cut off of 6 mm for the FO diameter (sensitivity, 73.3 %; specificity, 72.2 %; area under the curve [AUC], 0.764) and 3.2 mm for the VSD diameter (sensitivity, 75 %; specificity, 75 %; AUC, 0.728) suggested urgent BAS.

CONCLUSION

Prenatal echocardiography performed after 37 weeks of gestation in fetuses with d-TGA provides valuable information to estimate the need for postnatal urgent BAS that would prevent immediate life-threatening complications.

Live-Birth Incidence of Isolated D-Transposition of Great Arteries-The Shift in Trends Due to Early Diagnosis

This is a single tertiary population-based study conducted at a center in southwest Romania. We retrospectively compared data obtained in two periods: January 2008-December 2013 and January 2018-December 2023. The global incidence of the transposition of great arteries in terminated cases, in addition to those resulting in live-born pregnancies, remained almost constant. The live-birth incidence decreased. The median gestational age at diagnosis decreased from 29.3 gestational weeks (mean 25.4) to 13.4 weeks (mean 17.2). The second trimester and the overall detection rate in the prenatal period did not significantly change, but the increase was statistically significant in the first trimester. The proportion of terminated pregnancies in fetuses diagnosed with the transposition of great arteries significantly increased (14.28% to 75%, p = 0.019).

Gut microbiota-derived cholic acid mediates neonatal brain immaturity and white matter injury under chronic hypoxia

Chronic hypoxia, common in neonates, disrupts gut microbiota balance, which is crucial for brain development. This study utilized cyanotic congenital heart disease (CCHD) patients and a neonatal hypoxic rat model to explore the association. Both hypoxic rats and CCHD infants exhibited brain immaturity, white matter injury (WMI), brain inflammation, and motor/learning deficits. Through 16s rRNA sequencing and metabolomic analysis, a reduction in B. thetaiotaomicron and P. distasonis was identified, leading to cholic acid accumulation. This accumulation triggered M1 microglial activation and inflammation-induced WMI. Administration of these bacteria rescued cholic acid-induced WMI in hypoxic rats. These findings suggest that gut microbiota-derived cholic acid mediates neonatal WMI and brain inflammation, contributing to brain immaturity under chronic hypoxia. Therapeutic targeting of these bacteria provides a non-invasive intervention for chronic hypoxia patients.

Atrial Septal Defect vs Ventricular Septal Defect: Getting the Right Mix in Transposition of the Great Arteries

Transposition of the great arteries (TGA) is the second most common cyanotic congenital cardiac defect and affects around 4.7 in 10,000 live births. Patients present at birth with profound cyanosis due to inadequate oxygen delivery to the systemic circulation. Typical management after birth involves the administration of prostaglandins and oxygen while awaiting surgical repair. Balloon atrial septostomy may be performed depending on the adequacy of the interatrial communication. In this case report, we present a challenging case of TGA ventricular septal defect (VSD) and pulmonary stenosis (PS), demonstrating the importance of bedside clinical examination along with applying basic management principles. The patient underwent a right modified Blalock-Taussig-Thomas shunt (BTT) along with left pulmonary artery (LPA) reconstruction and main pulmonary artery band as an initial palliative procedure. The patient deteriorated post-operatively, with increasing desaturations and oxygen requirements. Though imaging suggested sufficient inter-circulatory mixing, the clinical picture of desaturation without respiratory distress and lack of response to oxygen and pulmonary vasodilatory therapy strongly suggested otherwise. The child therefore underwent a balloon atrial septostomy. Their clinical condition improved and they were discharged three days later. We describe this case's clinical course, medical and surgical management, and learning points.

Outcomes of neo-aortic valve and root surgery late after arterial switch operation

BACKGROUND

Neo-aortic root dilatation and valve regurgitation are emerging problems late after arterial switch operation (ASO). We sought to evaluate the prevalence and outcomes of neo-aortic root or valve reoperation after ASO.

METHODS

All patients with biventricular circulation who underwent an ASO between 1983 and 2015 were included at a single institution.

RESULTS

In our cohort of 782 late ASO survivors, the median duration of follow-up was 18.1 years (interquartile range [IQR], 11.3-25.6 years). During follow-up, 47 patients (6.0%) underwent 60 reoperations on the neo-aortic valve/root. The first neo-aortic valve/root reoperation occurred at a median of 15.2 years (IQR, 7.8-18.4 years) after ASO. Operations included mechanical Bentall (31.9%; n = 15), aortic valve repair (25.5%; n = 12), mechanical aortic valve replacement (AVR) (21.3%; n = 10), valve-sparing root replacement (19.1%; n = 9), and the Ross procedure (2.1%; n = 1). There was 1 late death (2.1%). Multivariable predictors of neo-aortic valve/root reoperation were bicuspid valve (hazard ratio [HR], 4.8; 95% confidence interval [CI], 2.1-10.7; P < .001), Taussig-Bing anomaly (HR, 3.0; 95% CI, 1.2-7.4; P < .02), previous pulmonary artery band (HR, 2.8; 95% CI, 1.2-6.3; P < .01) and left ventricular outflow tract obstruction before ASO (HR, 2.4; 95% CI, 1.0-5.8; P < .04). Freedom from neo-aortic valve or root reoperation was 98.0% (95% CI, 96.7%-98.8%) at 10 years, 93.3% (95% CI, 90.8%-95.2%) at 20 years, and 88.5% (95% CI, 84.1%-91.8%) at 30 years after ASO. Among the 47 patients who underwent neo-aortic reoperation, freedom from AVR was 82.3% (95% CI, 67.7%-90.7%) at 10 years, 58.0% (95% CI, 41.8%-71.2%) at 20 years, and 43.2% (95% CI, 27.0%-58.3%) at 25 years after ASO.

CONCLUSIONS

The need for neo-aortic valve or root reoperation surpasses 10% by 30 years post-ASO. Evolving understanding of the mechanisms of neo-aortic valve insufficiency and techniques of neo-aortic valve repair may decrease the need for AVR.

Analysis of haemodynamics surrounding blood transfusions after the arterial switch operation: a pilot study utilising real-time telemetry high-frequency data capture

BACKGROUND

Packed red blood cell transfusions occur frequently after congenital heart surgery to augment haemodynamics, with limited understanding of efficacy. The goal of this study was to analyse the hemodynamic response to packed red blood cell transfusions in a single cohort, as "proof-of-concept" utilising high-frequency data capture of real-time telemetry monitoring.

METHODS

Retrospective review of patients after the arterial switch operation receiving packed red blood cell transfusions from 15 July 2020 to 15 July 2021. Hemodynamic parameters were collected from a high-frequency data capture system (SickbayTM) continuously recording vital signs from bedside monitors and analysed in 5-minute intervals up to 6 hours before, 4 hours during, and 6 hours after packed red blood cell transfusions-up to 57,600 vital signs per packed red blood cell transfusions. Variables related to oxygen balance included blood gas co-oximetry, lactate levels, near-infrared spectroscopy, and ventilator settings. Analgesic, sedative, and vasoactive infusions were also collected.

RESULTS

Six patients, at 8.5[IQR:5-22] days old and weighing 3.1[IQR:2.8-3.2]kg, received transfusions following the arterial switch operation. There were 10 packed red blood cell transfusions administered with a median dose of 10[IQR:10-15]mL/kg over 169[IQR:110-190]min; at median post-operative hour 36[IQR:10-40]. Significant increases in systolic and mean arterial blood pressures by 5-12.5% at 3 hours after packed red blood cell transfusions were observed, while renal near-infrared spectroscopy increased by 6.2% post-transfusion. No significant changes in ventilation, vasoactive support, or laboratory values related to oxygen balance were observed.

CONCLUSIONS

Packed red blood cell transfusions given after the arterial switch operation increased arterial blood pressure by 5-12.5% for 3 hours and renal near-infrared spectroscopy by 6.2%. High-frequency data capture systems can be leveraged to provide novel insights into the hemodynamic response to commonly used therapies such as packed red blood cell transfusions after paediatric cardiac surgery.

Hemodynamic simulation of complete transposition of the great arteries for optimal treatment strategies based on its circulatory physiology

Our study aimed to elucidate the role of different shunts and provide novel insights into optimal treatment approaches for complete transposition of the great arteries (TGA), which is characterized by unique and complicated circulatory dynamics. We constructed a computational cardiovascular TGA model and manipulated cardiovascular parameters, such as atrial septal defect (ASD) and patent ductus arteriosus (PDA) sizes, to quantify their effects on oxygenation and hemodynamics. In addition, ASD flow patterns were investigated as innovative indications for balloon atrial septostomy (BAS). Our model of TGA with an intact ventricular septum (TGA-IVS) showed that a large ASD can achieve sufficient mixing for survival without PDA, and the presence of PDA is detrimental to oxygen delivery. A treatment strategy for TGA-IVS that enlarges the ASD as much as possible by BAS and PDA closure would be desirable. In TGA with a ventricular septal defect (TGA-VSD), the VSD allows for higher oxygenation and reduces the detrimental effects of PDA on systemic circulation. In TGA-VSD, both strategies of enlarging the ASD by BAS with a closed PDA and adjusting the PDA in response to pulmonary vascular resistance (PVR) reduction without BAS may be effective. The simulated ASD flow patterns showed that the sharp peak left-to-right flow pattern in systole (σ-wave) reflected the hemodynamically significant ASD size, independent of PDA, VSD, and PVR. The ASD flow pattern visualized by Doppler echocardiography provides clinical insights into the significance of an ASD and indications for BAS, which are not readily apparent through morphological assessment.NEW & NOTEWORTHY Complete transposition of the great arteries (TGA) represents complex and unique circulation that is dependent on blood mixing through multiple interacting shunts. Consequently, the role of each shunt and the treatment strategy remain unclear. We developed a mathematical model of TGA circulation, revealing the significant influence of atrial septal defect (ASD) on oxygenation and hemodynamics. The blood flow pattern through the ASD reflects its hemodynamic impact and helps determine treatment strategies.

Cardiac Catheterization Interventions in the Right Ventricular Outflow Tract and Branch Pulmonary Arteries Following the Arterial Switch Operation

The arterial switch operation for d-transposition of the great arteries achieves anatomic repair but creates the potential for right ventricular outflow tract obstruction as a result of the LeCompte maneuver. The resultant right ventricular hypertension is generally well tolerated but a select group are referred for cardiac catheterization. The outcomes of these catheterizations have not been well described. The objective of this study was to describe the degree and nature of right ventricular outflow tract obstruction found during cardiac catheterization among patients following the arterial switch operation as well as determine the rate of intervention and assess the acute impact of any catheter intervention undertaken. We conducted a retrospective study of patients after arterial switch operation with the LeCompte maneuver and subsequent right heart catheterization. Descriptive statistics were reported, and paired sample t tests were used for analysis. 544 children had an arterial switch operation, of which 110 children (20%) had a cardiac catheterization procedure after surgery and 11% had a right heart catheterization. Of the right heart catheterizations, 90% had an intervention (balloon and/or stent). In the interventional group, the right ventricle to systemic pressure ratio decreased modestly, from 2/3 to half systemic, after balloon dilation and/or stent placement (p < 0.01). No serious complications were observed.

Growth of the Neo-Aortic Root and Prognosis of Transposition of the Great Arteries

BACKGROUND

Neo-aortic root dilatation can lead to significant late morbidity after the arterial switch operation (ASO) for dextro-transposition of the great arteries (d-TGA).

OBJECTIVES

We sought to examine the growth of the neo-aortic root in d-TGA.

METHODS

A single-center, retrospective cohort study of patients who underwent the ASO between July 1, 1981 and September 30, 2022 was performed. Morphology was categorized as dextro-transposition of the great arteries with intact ventricular septum (d-TGA-IVS), dextro-transposition of the great arteries with ventricular septal defect (d-TGA-VSD), and double-outlet right ventricle-transposition of the great arteries type (DORV-TGA). Echocardiographically determined diameters and derived z scores were measured at the annulus, sinus of Valsalva, and sinotubular junction immediately before the ASO and throughout follow-up. Trends in root dimensions over time were assessed using linear mixed-effects models. The association between intrinsic morphology and the composite of moderate-severe aortic regurgitation (AR) and neo-aortic valve or root intervention was evaluated with univariable and multivariable Cox proportional hazards models.

RESULTS

Of 1,359 patients who underwent the ASO, 593 (44%), 666 (49%), and 100 (7%) patients had d-TGA-IVS, d-TGA-VSD, and DORV-TGA, respectively. Each patient underwent a median of 5 echocardiograms (Q1-Q3: 3-10 echocardiograms) over a median follow-up of 8.6 years (range: 0.1-39.3 years). At 30 years, patients with DORV-TGA demonstrated greater annular (P < 0.001), sinus of Valsalva (P = 0.039), and sinotubular junction (P = 0.041) dilatation relative to patients with d-TGA-IVS. On multivariable analysis, intrinsic anatomy, older age at ASO, at least mild AR at baseline, and high-risk root dilatation were associated with moderate-severe AR and neo-aortic valve or root intervention at late follow-up (all P < 0.05).

CONCLUSIONS

Longitudinal surveillance of the neo-aortic root is warranted long after the ASO.

Simultaneous Double Balloon Dilatation for Supravalvar Pulmonary Obstruction After Arterial Switch Operation

The optimal approach for supravalvar right ventricular outflow tract obstruction(RVOTO) after arterial switch operation(ASO) is unclear. The results of percutaneous balloon dilatation have been variable. We report the results of simultaneous double balloon dilation for RVOTO after ASO. Sixteen patients (1.3(0.7-3.8) years; 9.8(8.1-15.1) kgs underwent the procedure at 14(8-44.5) months after ASO. Salient technical features included placement of balloons over stiff guide-wires positioned in both branch pulmonary arteries to enable dilation of the distal-most main pulmonary artery (MPA) with high inflation pressures (~ 12-14 atmospheres) and short inflation-deflation cycles. Effective balloon size was based on the PA annulus or MPA distal to the narrowing. The final balloon: narrowest segment diameter ratio was 2.7. Following dilation, the right ventricle to systemic systolic pressure ratio decreased from 0.9 ± 0.18 to 0.52 ± 0.16 (p  < 0.001) and mean RVOT gradient from 78 ± 18 to 34 ± 13.9 mmHg (p < 0.001). Narrowest diameter improved from 5.4 ± 2.2 to 9.2 ± 2.2 mm. There were no major complications. Two patients with inadequate relief (final RV-systemic ratios: 1.03 and 0.7) were referred for surgery. At median follow up of 9 months, IQR 7-22, range 5-73, others are free of re interventions with median RVOT gradient of 42, IQR 27-49, range 21-55 mmHg. The immediate and short-term follow up results of double balloon dilatation for supravalvar RVOTO is encouraging and may avoid the need for repeat surgery in the majority of patients. Further follow up is needed to determine the long-term durability of the results.

30 years' experience with the arterial switch operation: risk of pulmonary stenosis and its impact on post-operative prognosis

Pulmonary stenosis is one of the most common complications in patients with transposition of the great arteries after the arterial switch operation. The reason for this is multifactorial and related to the anterior shift of the pulmonary trunk during the LeCompte manoeuvre, the complex suture line required to fill the gaps after harvesting the coronary arteries, and the need for patch implantation to maintain a tensionless anastomosis.We reviewed all patients with transposition of the great arteries operated on at our institute between 1991 and 2020 to establish the frequency of pulmonary stenosis during post-operative follow-up, reinterventions, and reoperations related to pulmonary stenosis and its potential risk factors.During the analysed period, we performed 848 arterial switch operations for simple and complex cases of transposition of the great arteries. The overall early mortality was 6.96%, and the late mortality was 2.53%. Among all study groups, 243 (28.66%) patients developed mild pulmonary stenosis, 43 patients (5.07%) developed moderate, and 45 patients (5.31%) developed severe pulmonary stenosis. During follow-up, 21 patients required interventions related to pulmonary stenosis. Pulmonary reconstruction with patches, aortic arch anomalies, and ventricular septal defects associated with transposition of the great arteries were significant risk factors. Nine patients required reoperation because of pulmonary artery stenosis with patch reconstruction of the pulmonary artery, aortic arch anomalies, and aortic cross-clamping time, increasing the risk of reoperation.Pulmonary stenosis in patients with transposition of the great arteries after the arterial switch operation is a common complication. If significant, it occurs early after surgery and is the most frequent reason for post-operative interventions and reoperations.

Assessment and management of neonates with unrepaired congenital heart disease

PURPOSE OF REVIEW

To review preoperative assessment and management of neonates with congenital heart disease (CHD).

RECENT FINDINGS

The spectrum for neonates with CHD can be wide and complex. An in-depth understanding of their physiology is the first step in assessing their hemodynamics and developing an effective therapeutic strategy.

SUMMARY

There is significant heterogeneity in the anatomy and physiology in newborns with CHD. Their complex pathophysiology can be simplified into seven basic subtypes, which include systolic dysfunction, diastolic dysfunction, excessive pulmonary blood flow, obstructed pulmonary blood flow, obstructed systemic blood flow, transposition physiology, and single ventricle physiology. It is important to note these physiologies are not mutually exclusive, and this review summarizes the hemodynamic and therapeutic strategies available for the preoperative neonate with CHD.

The impact of COVID-19 on a South African pediatric cardiac service: implications and insights into service capacity

Background and Objectives

The Western Cape public pediatric cardiac service is under-resourced. COVID-19 regulations are likely to have long-term effects on patient care but may provide insight into service capacity requirements. As such, we aimed to quantify the impact of COVID-19 regulations on this service.

Methods

An uncontrolled retrospective pre-post study of all presenting patients over two, one-year periods; the pre-COVID-19 period (01/03/2019-29/02/2020) and the peri-COVID-19 period (01/03/2020-28/02/2021).

Results

Admissions decreased by 39% (624 to 378) and cardiac surgeries decreased by 29% (293 to 208) in the peri-COVID-19 period, with an increase in urgent cases (PR:5.99, 95%CI:3.58-10.02, p < 0.001). Age at surgery was lower in the peri-COVID-19 period, 7.2 (2.4-20.4) vs. 10.8 (4.8-49.2) months (p < 0.05), likewise, age at surgery for transposition of the great arteries (TGA) was lower peri-COVID-19, 15 (IQR:11.2-25.5) vs. 46 (IQR:11-62.5) days (p < 0.05). Length of stay 6 (IQR:2-14) vs. 3 days (IQR:1-9) (p < 0.001), complications (PR:1.21, 95%CI:1.01-1.43, p < 0.05), and age-adjusted delayed-sternal-closure rates (PR:3.20, 95%CI:1.09-9.33, p < 0.05) increased peri-COVID-19.

Conclusion

Cardiac procedures were significantly reduced in the peri-COVID-19 period which will have implications on an overburdened service and ultimately, patient outcomes. COVID-19 restrictions on elective procedures freed capacity for urgent cases, demonstrated by the absolute increase in urgent cases and significant decrease in age at TGA-surgery. This facilitated intervention at the point of physiological need, albeit at the expense of elective procedures, and also revealed insights into capacity requirements of the Western Cape. These data emphasize the need for an informed strategy to increase capacity and reduce backlog whilst ensuring minimal morbidity and mortality.Graphical Abstract.

A Diagnostic Dilemma: Transposition of the Great Arteries

Transposition of the great arteries (TGA) remains one of the most common and severe underdiagnosed congenital cardiac anomalies in the prenatal period. Unfortunately, despite advances in prenatal ultrasound screening, the detection rate of major congenital heart defects (CHDs) remains low. We present the case of a preterm male infant delivered limp with generalized cyanosis and in respiratory distress at 36 weeks gestation with postnatal echocardiography (ECHO) depicting dextro-TGA (d-TGA). Maternal prenatal targeted fetal anomaly ultrasonography at 18 weeks gestation showed abnormal right ventricle and right ventricular outflow tract. Subsequent two-time repeat fetal ECHO showed ventricular septal defect. This case represents how challenging and unrecognized critical CHDs can be. Furthermore, it highlights the need for clinicians to have a high index of suspicion when newborns present with clinical manifestations of critical CHDs and manage it accordingly to avoid severe complications.

Socio-demographic parameters and non-cardiac comorbidity related to self-perceived quality of life in young adults after neonatal arterial switch operation for transposition of the great arteries

Evaluating the relation of non-cardiac comorbidity and socio-demographic factors to physical and mental health-related quality of life (QOL) which has been partially found at elevated risk in young adults after neonatal arterial switch operation (ASO) for transposition of the great arteries (TGA). In a prospective reassessment study, results of 92 unselected young adults (22.8 ± 2.6 years) having undergone evaluation of QOL (SF-36) were related to non-cardiac comorbidity with special respect to neurologic and psychiatric comorbidity and to socio-demographic parameters. Neurologic (14%) contrary to psychiatric comorbidities (6.5%) were more frequent than in the general population. The educational level was higher, the rate of unemployment was double as high compared to the average German population. Significant inverse relations (p = 0.006 to 0.033) existed between physical health domains (physical functioning and general health perception) and non-cardiac, neurologic, and psychiatric comorbidity, as well as correlations between the latter domains and socio-economic status, educational level, and worse employment status (Spearman 0.22-0.41, p < 0.0001 to 0.036). Mental health domains (vitality, social functioning, psychical health) were significantly inversely related with neurologic and psychiatric comorbidity (p = 0.002 to 0.048) and correlated with higher educational level (Spearman 0.25, p = 0.019). Neurologic and psychiatric comorbidities and socio-demographic parameters are significant risk factors for a reduced QOL concerning physical and mental health in young adults with TGA after ASO. Standardized QOL measurement should be part of routine screening programs to detect subclinical physical, neurodevelopmental, and psychosocial comorbidity.

Pericardial Effusions After the Arterial Switch Operation: A PHIS Database Review

Background: Pericardial effusion (PCE) is a significant complication after pediatric cardiac surgery. This study investigates PCE development after the arterial switch operation (ASO) and its short-term and longitudinal impacts. Methods: A retrospective review of the Pediatric Health Information System database. Patients with dextro-transposition of the great arteries who underwent ASO from January 1, 2004, to March 31, 2022, were identified. Patients with and without PCE were analyzed with descriptive, univariate, and multivariable regression statistics. Results: There were 4896 patients identified with 300 (6.1%) diagnosed with PCE. Thirty-five (11.7%) with PCE underwent pericardiocentesis. There were no differences in background demographics or concomitant procedures between those who developed PCE and those who did not. Patients who developed PCE more frequently had acute renal failure (N = 56 (18.7%) vs N = 603(13.1%), P = .006), pleural effusions (N = 46 (15.3%) vs N = 441 (9.6%), P = .001), mechanical circulatory support (N = 26 (8.7%) vs N = 199 (4.3%), P < .001), and had longer postoperative length of stay (15 [11-24.5] vs 13 [IQR: 9-20] days). After adjustment for additional factors, pleural effusions (OR = 1.7 [95% CI: 1.2-2.4]), and mechanical circulatory support (OR = 1.81 [95% CI: 1.15-2.85]) conferred higher odds of PCE. There were 2298 total readmissions, of which 46 (2%) had PCE, with no difference in median readmission rate for patients diagnosed with PCE at index hospitalization (median 0 [IQR: 0-1] vs 0 [IQR: 0-0], P = .208). Conclusions: PCE occurred after 6.1% of ASO and was associated with pleural effusions and mechanical circulatory support. PCE is associated with morbidity and prolonged length of stay; however, there was no association with in-hospital mortality or readmissions.

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.

The management of newborns with critical congenital heart diseases prior to transport to a cardiac center

Critical congenital heart diseases (CCHD) are important causes of mortality and morbidity in the newborn period. Even after diagnosis, their management could be seriously compromised by the unplanned delivery in hospitals with limited expertise and resources. The newborn may spend days or week before transport putting a significant burden on the neonatal team to manage such challenging diseases. In this review, the management principles of each individual pathology are discussed in the setting before transport to cardiac centers. Understanding these principles will help the treating teams evaluate and manage those complex conditions. The review avoids the advanced discussion on the management of CCHDs not applicable to the pre-transport setup. It highlights the critical elements in the maintenance of normal hemodynamics specific to each pathology and their variation.

Timing of Balloon Atrial Septostomy in Patients with d-TGA and Association with Birth Location and Patient Outcomes

Patients with d-looped transposition of the great arteries (d-TGA), especially those without an adequate atrial septal defect, can experience severe hypoxemia and hemodynamic compromise in the neonatal period. This can be mitigated by urgent balloon atrial septostomy (BAS). However, some patients with d-TGA are born at centers without this capability. The aim of this retrospective study of d-TGA patients who had urgent or emergent BAS at our institution between 2010 and 2021 was to evaluate time from birth to BAS for infants born at a tertiary care center as compared to those requiring transport from other institutions and to examine correlation between time to BAS and patient outcomes. Our primary outcome was time from birth to BAS. Secondary outcomes included hospital and ICU length of stay, mortality, and evidence of pulmonary or neurologic abnormalities including pulmonary hypertension, abnormal neuroimaging, or seizures. Of 96 patients, 67 (70%) were born at our institution. The median time to BAS was 4 h for patients born at our institution vs. 14.1 h for those born elsewhere (p < .0001). A longer time from birth to BAS was associated with longer ICU (r = 0.21, p = 0.046) and hospital length of stay (r = 0.24, p = 0.02) and increased likelihood of elevated right ventricular pressure on post-operative discharge echocardiogram (p = 0.01). There were no differences in mortality between the groups. Therefore, prenatal planning for patients with known d-TGA should include a delivery plan with access to urgent BAS.

Renal Outcomes in Neonates and Infants with Transposition Physiology Undergoing Arterial Switch Procedure

Acute kidney injury (AKI) in children with Transposition of Great arteries (TGA) undergoing Arterial Switch operation (ASO) is an important complication in the post-operative period associated with worse outcomes. AKI in children post open cardiac surgery has been well studied, with lesser data in literature pertaining to TGA and its sub-types specifically. This was a prospective, observational study enrolling infants with TGA undergoing ASO at a single center over a span of a decade from January 2010 to December 2020. The infants were followed during the duration of ICU and hospital stay, with documentation of baseline and intraoperative parameters as well as post-operative course. Out of 145 infants enrolled in the study, 83.1% developed AKI with majority (83.9%) having stage 1 AKI. Higher odds of AKI were seen in infants requiring Norepinephrine [odds ratio - 16.76 (95% CI 2.19-128.2), p < 0.001] and those who developed gram-negative infections [2.81 (1.04-7.56), p - 0.036]. Infants with AKI had significantly higher vasoactive-inotropic support at day 1 than those without AKI [16 (12.5-21.50 vs 13 (10.25-15.75), p - 0.014]. Seventeen infants in the AKI group (14%) died as opposed to none in the non-AKI group (p = 0.076). Median hours of ventilator support required were significantly higher in those with AKI than those who did not develop AKI (48 vs 45.5 p = 0.015). The infants with ASO + ASD + PDA (53% of neonates who died) were younger, had less weight at admission, more gram-negative sepsis and need for dopamine, as compared to ASO + VSD + ASD (23.5% of mortality) and ASO + ASD + VSD + aortic arch repair (23.5% of mortality). AKI in infants with TGA undergoing ASO is common and associated with poorer outcomes. In this subpopulation, AKI development is associated most commonly with hemodynamic instability and infections. This is the first study, looking at outcomes of TGA depending on the sub-types of ASO surgeries done in the infants [ASO with ASD + PDA or ASD + VSD or ASD + VSD + Arch Repair].

Functional and morphometric changes in children after neonatal arterial switch operation for transposition of the great arteries

Background

The increase in the survival of patients with D-Transposition of the great arteries (TGA) after arterial switch operation (ASO) has now turned our focus to the evaluation of mid and long-term outcomes. Although most patients are followed by conventional echocardiography, the study of cardiac functionality and morphometric parameters in children with TGA after ASO is scarce. The present study aims to describe the functional and morphometric echocardiographic changes in children after ASO.

Methods

We performed an observational study in patients aged 1-5 years with TGA who underwent neonatal ASO. Morphometric and functional echocardiographic parameters were analyzed in 21 patients and compared with 52 age-matched healthy controls.

Results

We found morphological and functional changes, especially in the right ventricle, which is more globular (right ventricle [RV] basal sphericity index 1.5 vs. 1.8, P = 0.016), and with a decreased systolic function compared to healthy controls (fractional area change 51 vs. 58%, P = 0.006; tricuspid annular plane systolic excursion 13 vs. 20 mm, P = 0.001; s' 7 vs. 12 cm/s, P = 0.001). In the speckle-tracking strain imaging, there was a decrease in the longitudinal deformation of the apical septal myocardium (-23% vs. -27%; P = 0.005). Preoperative systemic overload to the right ventricle could be an important factor in the origin of these changes.

Conclusions

In patients with TGA after ASO, there are morphometric and functional echocardiographic changes, such as globular form and decreased function, especially in the RV; the effect of these changes on long-term outcomes would require prospective follow-up studies.

Lesion-specific mortality due to congenital heart disease in U.S. adults from 1999 to 2017

BACKGROUND

Adults with congenital heart disease (ACHD) comprise an increasing proportion of individuals living with CHD in the United States (US) although little is known regarding lesion or age-specific mortality in the modern era. Our study aimed to describe current era ACHD mortality rates by age and CHD lesion and provide temporal mortality rate trends for the last two decades.

METHODS

We conducted a 19-year analysis (1999-2017) of publicly available, de-identified Multiple Cause of Death data compiled and produced by the National Center for Health Statistics. Age and lesion-specific mortality rates were calculated using joinpoint regression.

RESULTS

ACHD mortality rates decreased by an average of 2%-4% per year for all adults. CHD lesions resulting in the highest ACHD-related mortality varied by age. Unlike the other lesions, mortality attributed to single ventricle physiology failed to improve in early adulthood (average of 1.6% increase per year). In decedents age 65 years or older, simpler forms of CHD like shunt lesions became more prominent contributors, accounting for 46% of deaths.

CONCLUSION

Rates of mortality due to ACHD have declined significantly for adults with CHD, however, continued mortality due to single ventricle physiology remains an area requiring improved strategies to increase survival.

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.

Dextro-transposition of the great arteries in one twin: case reports and literature review

BACKGROUND

Dextro-transposition of the great arteries (D-TGA) is a rare congenital heart disease, as it affects only 0.02-0.05% of live births. It is the second most common cyanotic heart disease following Tetralogy of Fallot. It has a male predominance. Fetal echocardiography is an optimal method for prenatal diagnosis of fetal D-TGA. In twin pregnancies, fetal D-TGA in one twin is very rare, especially in monochorionic-diamniotic twin pregnancies. Herein, we report a case of D-TGA in one twin in two dichorionic-diamniotic twin pregnancies and one monochorionic-diamniotic twin pregnancy from January 2018 to June 2021.

CASE DESCRIPTION

One twin with D-TGA was diagnosed by fetal echocardiography in the second trimester, and the co-twin was normal in all three cases. A multidisciplinary team provided extensive counseling regarding the D-TGA twin and the co-twin, and adequate perinatal management was provided. In cases 1, 2, and 3, the mothers underwent cesarean sections at 37 weeks + 2 days, 34 weeks + 5 days, and 36 weeks + 1 day, respectively. In case 1, which involved a female D-TGA neonate with birth weight 2,410 g, an emergent atrial septostomy was performed at 20 h after birth, and the neonate underwent atrial switch operation (ASO) 24 days after birth. In case 2, involving a male D-TGA neonate with a birth weight of 2,380 g, ASO was performed 24 days after birth. In case 3, involving a female D-TGA neonate with birth weight 2,240 g, ASO was performed 19 days after birth and delayed sternal closure was performed 4 days later. All six infants showed normal development during follow-up.

CONCLUSIONS

Early antenatal diagnosis of D-TGA in one fetus of a twin pregnancy is significantly important. A multidisciplinary team should carry individual evaluation and integrated management of the D-TGA twin and co-twin during the pregnancy and perinatal period. After birth, delayed ductus arteriosus closure in the D-TGA twins should be performed when necessary and individualized timings for arterial switch operation should be considered.

Branch pulmonary artery stenosis after arterial switch operation: The effect of preoperative anatomic factors on reintervention

BACKGROUND

We hypothesized that preoperative patient characteristics and branch pulmonary artery (PA) size might influence the rate of postoperative branch PA reintervention in patients with transposition of the great arteries who undergo the arterial switch operation (ASO).

METHODS

The retrospective single-center study included 262 consecutive (2008-2017) newborns who underwent the ASO. Demographic characteristics, echocardiography, and clinical outcomes were reviewed. Competing risk analysis modeled incidence of branch PA reintervention and cause-specific hazard regression for predictors analyses.

RESULTS

Median age and weight were 7 (range, 5-11) days and 3.4 (range, 3.1-3.8) kg, respectively. Various types of early branch PA reinterventions (concomitant revision or reintervention during the intensive care unit stay) were required in 28 (10.7%) patients. These patients had prolonged ventilation (P < .001), intensive care unit duration (P < .001), worse right ventricular function (P = .043), and high in-hospital mortality (P = .010). Branch PA dimensions significantly decreased immediately after ASO compared with baseline measurements. The median follow-up duration was 20.8 (range, 0.9-44.7) months. Branch PA reintervention was common among survivors without early reinterventions (9.4%), and even more frequent among those with early reinterventions (25%). Subsequent reintervention (all catheter-based) was necessary for more than one-third of patients after initial branch PA reintervention. The multivariable analysis showed preoperative dimension of the left PA (hazard ratio, 0.527 [95% CI, 0.337-0.823]; P = .005), and right PA (hazard ratio, 0.503 [95% CI, 0.318-0.796]; P = .003) were independently associated with late branch PA reinterventions.

CONCLUSIONS

Branch PA reintervention was common and often required surgical or catheter-based reinterventions after ASO. PA branch diameters became significantly smaller after ASO. Smaller preoperative branch PA predicted late branch PA reintervention, indicating a smaller margin of geometrical tolerance to this effect.

Whole genome sequencing in transposition of the great arteries and associations with clinically relevant heart, brain and laterality genes

BACKGROUND

The most common cyanotic congenital heart disease (CHD) requiring management as a neonate is transposition of great arteries (TGA). Clinically, up to 50% of TGA patients develop some form of neurodevelopmental disability (NDD), thought to have a significant genetic component. A "ciliopathy" and links with laterality disorders have been proposed. This first report of whole genome sequencing in TGA, sought to identify clinically relevant variants contributing to heart, brain and laterality defects.

METHODS

Initial whole genome sequencing analyses on 100 TGA patients focussed on established disease genes related to CHD (n = 107), NDD (n = 659) and heterotaxy (n = 74). Single variant as well as copy number variant analyses were conducted. Variant pathogenicity was assessed using the American College of Medical Genetics and Genomics-Association for Molecular Pathology guidelines.

RESULTS

Fifty-five putatively damaging variants were identified in established disease genes associated with CHD, NDD and heterotaxy; however, no clinically relevant variants could be attributed to disease. Notably, case-control analyses identified significantly more predicted-damaging, silent and total variants in TGA cases than healthy controls in established CHD genes (P < .001), NDD genes (P < .001) as well as across the three gene panels (P < .001).

CONCLUSION

We present compelling evidence that the majority of TGA is not caused by monogenic rare variants and is most likely oligogenic and/or polygenic in nature, highlighting the complex genetic architecture and multifactorial influences on this CHD sub-type and its long-term sequelae. Assessment of variant burden in key heart, brain and/or laterality genes may be required to unravel the genetic contributions to TGA and related disabilities.

Cyanosis in a Newborn Immediately after Birth

Cyanosis in a Newborn Immediately after BirthA male neonate, weighing 3.9 kg, was delivered via Cesarean section at 39 weeks of gestation. He cried immediately after birth, but his whole body appeared blue and he had low muscle tone that did not improve with suctioning and stimulation. Blow-by with 100% oxygen was initiated, and pulse oximetry on his left hand measured 40%. What is the diagnosis?

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.

Prenatal Delineation of Coronary Anatomy in Dextro-Transposition of Great Arteries

Background

Dextro-transposition of the great arteries (D-TGA) is the second-most common cyanotic congenital heart disease with variable coronary artery anatomy. The arterial switch procedure has revolutionized outcomes for this defect, with coronary anatomy being a key determinant of both short- and long-term outcomes following surgical repair. The assessment of coronary anatomy is usually undertaken in the postnatal period by transthoracic echocardiography, with assessment prenatally not being well studied. We sought to assess the feasibility of delineating the coronary arteries on fetal echocardiograms in a small cohort of patients followed prenatally.

Methods

This was a retrospective review of fetuses with D-TGA from 2008 to 2018. Patients with prenatal diagnosis of D-TGA were reviewed for the assessment of coronary artery anatomy. Details of coronary artery anatomy diagnosed prenatally were compared with postnatal transthoracic echocardiograms and intraoperative findings.

Results

Thirty-four fetuses with findings of D-TGA on prenatal echocardiograms were reviewed. 14/34 fetuses had attempted delineation of coronary artery anatomy, with average gestational age of 28 weeks (range 23-31 weeks) at the time of diagnosis. Two-dimensional and color Doppler imaging of the coronary arteries on both short and long axis images were performed, with complete delineation being possible in ~ 86% of fetuses. These findings were confirmed postnatally.

Conclusions

Fetuses with D-TGA can have variable coronary artery anatomy which drives postnatal outcomes. Our study describes a cohort of patients with D-TGA wherein coronary artery anatomy was assessed. We demonstrate that coronary artery evaluation is feasible prenatally with optimal imaging techniques, being more successful after 25 weeks' gestation. The potential knowledge of dangerous variants can help with referral to centers of excellence for appropriate postnatal management and facilitate prenatal care accordingly.

Right ventricular afterload in repaired D-TGA is associated with inefficient flow patterns, rather than stenosis alone

Treatment of D- transposition of great arteries (DTGA) involves the Arterial Switch Operation (ASO), which can create PA branch stenosis (PABS) and alter PA blood flow energetics. This altered PA flow may contribute to elevated right ventricular (RV) afterload more significantly than stenosis alone. Our aim was to correlate RV afterload and PA flow characteristics using 4D flow cardiac magnetic resonance (CMR) imaging of a mock circulatory system (MCS) incorporating 3D printed replicas. CMR imaging and clinical characteristics were analyzed from 22 ASO patients (age 11.9 ± 8.7 years, 68% male). Segmentation was performed to create 3D printed PA replicas that were mounted in an MRI-compatible MCS. Pressure drop across the PA replica was recorded and 4D flow CMR acquisitions were analyzed for blood flow inefficiency (energy loss, vorticity). In post-ASO patients, there is no difference in RV mass (p = 0.07), nor RV systolic pressure (p = 0.26) in the presence or absence of PABS. 4D flow analysis of MCS shows energy loss is correlated to RV mass (p = 0.01, r = 0.67) and MCS pressure differential (p = 0.02, r = 0.57). Receiver operating characteristic curve shows energy loss detects elevated RV mass above 30 g/m² (p = 0.02, AUC 0.88) while index of PA dimensions (Nakata) does not (p = 0.09, AUC 0.79). PABS alone does not account for differences in RV mass or afterload in post-ASO patients. In MCS simulations, energy loss is correlated with both RV mass and PA pressure, and can moderately detect elevated RV mass. Inefficient PA flow may be an important predictor of RV afterload in this population.

Impact of ductus arteriosus constriction and restrictive foramen ovale on global hemodynamics for term fetuses with d-TGA

The ductus arteriosus (DA) constriction and restrictive foramen ovale (FO) are known as the leading cause of compromise and death of fetuses with dextro-transposition of the great arteries (d-TGA). Although the d-TGA fetal hemodynamics is of great importance in making diagnosis and management of the congenital heart defect, it remains poorly understood, particularly in terms of abnormal DA and FO. In this study, we developed a closed-loop 0-1D multiscale model of the fetal cardiovascular system (CVS) specified for the d-TGA circulation and conducted a systematic study of the impact of the DA constriction and restrictive FO on fetal hemodynamics. We found that the DA constriction led to a pronounced increase in the pulmonary artery pressure, pulmonary and mitral valve (PV and MV) regurgitation as well as left heart volume; the restrictive FO was responsible for reducing MV E/A ratio, ie, the ratio of peak early filling and late diastolic filling velocities, and PV peak systolic flow (PSV) but could increase both aortic valve (AV) PSV and aortic isthmus systolic index (ISI). Moreover, the amount of blood flowing through the DA was observed equivalent to that through the FO; the influence of DA constriction on the cerebral and placental perfusions are larger than that of the FO. Our results demonstrate that the proposed fetal cardiovascular model may be a useful tool for studying the underlying mechanisms associated with d-TGA fetal circulation and providing insights into its complex physiology and pathology.

Lessons learned from ECMO support in pediatric patients with D-transposition of the great arteries: preoperative, intraoperative and postoperative

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) support on D-transposition of the great arteries (D-TGA) carries formidable challenges.

METHODS

A retrospective study was performed on pediatric patients with D-TGA supported by ECMO from July 2007 to December 2019. This study summarized the clinical experience of ECMO support in pediatric patients with D-TGA preoperative, intraoperative, and postoperative.

RESULTS

Overall, 16 children with D-TGA received ECMO support during this period. Two (2 of 16) were supported before cardiac surgery, 3 (3 of 16) were supported postoperatively in the intensive care unit, and 11 (11 of 16) failed to wean off cardiopulmonary bypass. Two cases of preoperative ECMO support for patients with D-TGA with an intact ventricular septum and restrictive atrial septum due to severe hypoxemia died. In this study, D-TGA with coronary artery malformation and other complicated deformities died (8 of 14), whereas uncomplicated D-TGA without coronary artery malformation all survived (6 of 14). The wean-off rate of ECMO patients supported in D-TGA was 62.5% (10 of 16), while the 30-day survival rate was 44% (7 of 16).

CONCLUSION

Although a promising ECMO weaning rate was obtained, 30-day survival of this population was frustrating, mainly attributed to the original anatomy of coronary arteries and the concomitant deformities.

Prenatal diagnosis and planned peripartum care improve perinatal outcome of fetuses with transposition of the great arteries and intact ventricular septum in low-resource settings

OBJECTIVE

To report on the feasibility of establishing a regional prenatal referral network for critical congenital heart defects (CHDs) and its impact on perinatal outcome of fetuses with transposition of the great arteries and intact ventricular septum (TGA-IVS) in low-resource settings.

METHODS

This was a retrospective study of consecutive fetuses with a diagnosis of TGA-IVS between January 2011 and December 2019 in Kochi, Kerala, India. A regional network for prenatal diagnosis and referral of patients with critical CHDs was initiated in 2011. Pregnancy and early neonatal outcomes were reported. The impact of the timing of diagnosis (prenatal or after birth) on age at surgery, perinatal mortality and postoperative recovery was evaluated.

RESULTS

A total of 82 fetuses with TGA-IVS were included. Diagnosis typically occurred later on in gestation, at a median of 25 (interquartile range (IQR), 21-32) weeks. The majority (78.0%) of affected pregnancies resulted in live birth, most (84.4%) of which occurred in a specialist pediatric cardiac centers. Delivery in a specialist center, compared with delivery in a local maternity center, was associated with a significantly higher rate of surgical correction (98.1% vs 70.0%; P = 0.01) and overall lower neonatal mortality (3.7% vs 50%; P = 0.001). The proportion of cases undergoing arterial switch operation after prenatal diagnosis of TGA-IVS increased significantly, along with the prenatal detection rate, over the study period (2011-2015, 11.1% vs 2016-2019, 29.4%; P = 0.001). Median age at surgery was significantly lower in the prenatally diagnosed group than that in the postnatally diagnosed group (4 days (IQR, 1-23 days) vs 10 days (IQR, 1-91 days); P < 0.001). There was no significant difference in postoperative mortality (2.0% vs 3.6%; P = 0.49) between the two groups.

CONCLUSIONS

This study demonstrates the feasibility of creating a network for prenatal diagnosis and referral of patients with critical CHDs, such as TGA, in low-resource settings, that enables planned peripartum care in specialist pediatric cardiac centers and improved neonatal survival. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

A case report of hepatocellular carcinoma derived from Rastelli procedure-related congestive liver disease

The prognosis of congenital heart disease in children has improved, but late complications in adulthood are becoming an important problem. One late complication after congenital heart surgery is congestive liver disease, leading to liver cirrhosis and hepatocellular carcinoma (HCC). The Rastelli procedure is one of the surgical methods for transposition of the great arteries. We present the first case of HCC derived from Rastelli procedure-related congestive liver disease in a 41-year-old male. The patient underwent the Rastelli operation at 2 years of age and right ventricular outflow tract reconstruction at 10 and 35 years of age due to right ventricular outflow tract obstruction. At 41 years of age, a hepatic tumor was detected by computed tomography. Abdominal enhancing computed tomography revealed a partially hypervascular tumor in segment 2 in early phase and wash-out in late phase. The patient was diagnosed with HCC and underwent left lateral segmentectomy of the liver, splenectomy, and partial gastrectomy. The patient was discharged on the 28th postoperative day without postoperative complications. In the management of patients after the Rastelli operation, surveillance for congestive liver disease and HCC development is important, even if the patients have undergone right ventricular outflow tract reconstruction.

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.

Risk Factors for Reoperation After Arterial Switch Operation

OBJECTIVE

The timing and nature of and risk factors for reoperation after the arterial switch operation in the setting of d-transposition of the great arteries requires further elucidation.

METHODS

A total of 403 patients who underwent arterial switch operation from 1986 to 2017 were reviewed. Institutional preference was for pulmonary artery reconstruction using a pantaloon patch of fresh autologous pericardium. The targets for coronary artery reimplantation were identified by intermittent root distension. Multivariable analysis was used to identify risk factors for reoperation.

RESULTS

Median follow-up was 8.6 years (interquartile range [IQR]: 2-16.9). Pulmonary arterioplasty was the most common reoperation (n = 11, 2.7%) at 3.3 years (IQR: 1.4-11.4) postoperatively. Subvalvar right ventricular outflow tract reconstruction (RVOTR) was required in nine (2.2%) patients at 2.5 years (IQR: 1.1-5.3) postoperatively. Aortic valve repair or replacement (AVR/r) was required in seven (1.7%) patients at 13.6 years (IQR: 10.0-15.8) postoperatively. Aortic root replacement (ARR) and Coronary Artery Bypass Graft/coronary patch arterioplasty were required in five (1.2%) patients each at 13.6 years (IQR: 11.0-15.3) and 11.3 years (IQR: 2.3-13.6) postoperatively, respectively. Taussig-Bing anomaly was a risk factor for any reoperation (P = .034). Risk factors for specific reoperations included ventricular septal defect for AVR/r (P = .038), Taussig-Bing anomaly for RVOTR (P = .004), and pulmonary artery banding for ARR (P = .028).

CONCLUSIONS

Pantaloon patch pulmonary artery reconstruction and intermittent neo-aortic root distension during coronary reimplantation have minimized respective outflow tract reoperations. Certain anatomic subsets carry different risks for late reoperation, and pulmonary artery and/or RVOT reinterventions tend to occur sooner than aortic reinterventions. Special attention to these higher risk subpopulations will be critical to optimizing lifelong outcomes.

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.

Urgent neonatal balloon atrial septostomy in simple transposition of the great arteries: predictive value of fetal cardiac parameters

OBJECTIVES

To investigate the impact of abnormal perinatal loading conditions on cardiac geometry and function in term fetuses and neonates with transposition of the great arteries with intact interventricular septum (simple TGA), and to explore the predictive value of fetal cardiac parameters for an urgent balloon atrial septostomy (BAS) after birth.

METHODS

This was a prospective longitudinal follow-up study of women delivering at term, including both uncomplicated pregnancies with normal outcome and pregnancies affected by fetal simple TGA. Conventional, spectral-tissue Doppler and speckle-tracking echocardiographic parameters were obtained within 1 week before delivery and within the first few hours after delivery. Neonates with simple TGA that required urgent BAS were assessed after the procedure and before corrective arterial switch surgery. Cardiac parameters were normalized by cardiac cycle length, ventricular end-diastolic length or end-diastolic dimension, as appropriate. Fetal and neonatal cardiac parameters were compared between simple-TGA cases and controls, and perinatal changes in the simple-TGA group were assessed. Receiver-operating-characteristics (ROC)-curve analysis was used to assess the predictive value of fetal cardiac parameters for urgent BAS after birth in the simple-TGA group.

RESULTS

A total of 67 pregnant women delivering at term were included in the study (54 normal pregnancies and 13 with a diagnosis of fetal simple TGA). Compared with normal term fetuses, term fetuses with simple TGA exhibited more globular hypertrophied ventricles, increased biventricular systolic function and diastolic dysfunction (right ventricular (RV) sphericity index (SI), 0.58 vs 0.54; left ventricular (LV)-SI, 0.55 vs 0.49; combined cardiac output (CCO), 483 vs 406 mL/min/kg; LV torsion, 4.3 vs 3.0 deg/cm; RV isovolumetric relaxation time (IVRT'), 127 vs 102 ms; P < 0.01 for all). Compared with normal neonates, neonates with simple TGA demonstrated biventricular hypertrophy, a more spherical right ventricle and altered systolic and diastolic functional parameters (RV-SI, 0.61 vs 0.43; RV myocardial performance index, 0.47 vs 0.34; CCO, 697 vs 486 mL/min/kg; LV-IVRT', 100 vs 79 ms; RV-IVRT', 106 vs 71 ms; P < 0.001 for all). Paired comparison of neonatal and fetal cardiac indices in the simple-TGA group showed persistence of the fetal phenotype, increased biventricular systolic myocardial contractility and CCO, and diastolic dysfunction (RV systolic myocardial velocity (S'), 0.31 vs 0.24 cm/s; LV-S', 0.23 vs 0.18 cm/s; CCO, 697 vs 483 mL/min/kg; LV torsion, 1.1 vs 4.3 deg/cm; P < 0.001 for all). Several fetal cardiac parameters in term fetuses with simple TGA demonstrated high predictive value for an urgent BAS procedure after birth. Our proposed novel fetal cardiac index, LV rotation-to-shortening ratio, as a potential marker of subendocardial dysfunction, for a cut-off value of ≥ 0.23, had an area under the ROC curve (AUC) of 0.94, sensitivity of 100% and specificity of 83%. For RV/LV end-diastolic area ratio ≥ 1.33, pulmonary-valve-to-aortic-valve-dimension ratio ≤ 0.89, RV/LV cardiac output ratio ≥ 1.38 and foramen-ovale-dimension-to-total-interatrial-septal-length ratio ≤ 0.27, AUC was 0.93-0.98, sensitivity was 86% and specificity was 83-100% for all.

CONCLUSIONS

Simple-TGA fetuses exhibited cardiac remodeling at term with more profound alterations in these cardiac parameters after birth, suggestive of adaptation to abnormal loading conditions and possible adaptive responses to hypoxemia. Perinatal adaptation in simple TGA might reflect persistence of the abnormal parallel arrangement of cardiovascular circulation and the presence of widely patent fetal shunts imposing volume load on the neonatal heart. The fetal cardiac parameters that showed high predictive value for urgent BAS after birth might reflect the impact of late-gestation pathophysiology and progressive hypoxemia on fetal cardiac geometry and function in simple TGA. If these findings are validated in larger prospective studies, detailed cardiac assessment of fetuses with simple TGA near term could facilitate improvements in perinatal management and refinement of the timing of postnatal intervention strategies to prevent adverse pregnancy outcomes. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Risk factors for transposition of the great arteries in Saudi population

Objectives:

To assess potential risk factors and their effect on the development of transposition of the great arteries (TGA).

Methods:

A retrospective case-control study of all patients diagnosed with TGA between 1999 to 2016 at King Abdulaziz Medical City, Riyadh, Saudi Arabia. Age and gender-matched controls were selected. Risk factors, including consanguinity, gestational diabetes, family history of congenital heart disease, parental age, and maternal parity, were collected. Regression modeling was used to analyze the effects of risk factors on the development of TGA.

Results:

A total of 206 patients with transposition of the great arteries were enrolled in the study. Transposition of the great arteries cases were divided into simple and complex TGA. Selected healthy controls were 446. In the studied cases, consanguinity was found in 95 (46%) of cases, gestational diabetes was diagnosed in 36 (17.5%) mothers, and 35 (17%) had a confirmed family history of congenital heart disease. When risk factors of the cases were compared to the controls, consanguinity, gestational diabetes, maternal age, and parity were found to significantly increase the incidence of TGA.

Conclusion:

Our study revealed significant risk factors for the development of transposition of great arteries including first degree consanguineous marriages, gestational diabetes, family history of congenital cardiac anomalies, and increasing maternal age and parity. These factors increased the risk by at least 2 folds.

Surgical procedures for coronary arteries in pediatric cardiac surgery: Risk factors and outcomes

BACKGROUND

Limited data exist regarding the coronary revascularization procedures needed during the repair of several congenital and pediatric cardiac malformations. We aimed to determine risk factors for in-hospital mortality and long-term outcomes of various pediatric coronary revascularization procedures.

METHODS

We retrospectively reviewed the records of 32 consecutive pediatric patients who underwent coronary revascularization procedures at our institution between May 1995 and June 2020. In-hospital mortality, risk factors, surgical indications, revascularization patency, and mid- and long-term follow-up data were investigated. Patients were categorized into the coronary artery bypass grafting (n = 11) and other coronary artery procedure (n = 21) groups.

RESULTS

The median age and weight of patients at the time of surgery were 9 months and 4.8 kg, respectively. There were five in-hospital deaths (5/32, 15.6%). The mortality rates were 27.2% (3/11) in the coronary artery bypass grafting group and 9.5% (2/21) in the other coronary artery procedure group (p = .206; 95% confidence interval: 0.496-25.563). The mortality rates for planned and rescue procedures were 8.3% (2/24) and 37.5% (3/8) (p = .06), respectively. The median follow-up time was 12.5 years. Control imaging studies for coronary patency were performed in 70.3% (19/27) of surviving patients. The overall coronary patency rate was 94.7% (18/19).

CONCLUSIONS

Pediatric coronary revascularization procedures with elective-planned indications can be performed with good outcomes. Young age and rescue and emergency procedures may carry an increased risk of in-hospital mortality, although not found to be statistically significant. Surviving patients require lifelong follow-up regarding the patency of reperfused coronary arteries.

Assessment of ventricular flow dynamics by 4D-flow MRI in patients following surgical repair of d-transposition of the great arteries

Objectives

To use 4D-flow MRI to describe systemic and non-systemic ventricular flow organisation and energy loss in patients with repaired d-transposition of the great arteries (d-TGA) and normal subjects.

Methods

Pathline tracking of ventricular volumes was performed using 4D-flow MRI data from a 1.5-T GE Discovery MR450 scanner. D-TGA patients following arterial switch (n = 17, mean age 14 ± 5 years) and atrial switch (n = 15, 35 ± 6 years) procedures were examined and compared with subjects with normal cardiac anatomy and ventricular function (n = 12, 12 ± 3 years). Pathlines were classified by their passage through the ventricles as direct flow, retained inflow, delayed ejection flow, and residual volume and visually and quantitatively assessed. Additionally, viscous energy losses (EL_v) were calculated.

Results

In normal subjects, the ventricular flow paths were well ordered following similar trajectories through the ventricles with very little mixing of flow components. The flow paths in all atrial and some arterial switch patients were more irregular with high mixing. Direct flow and delayed ejection flow were decreased in atrial switch patients’ systemic ventricles with a corresponding increase in residual volume compared with normal subjects (p = 0.003 and p < 0.001 respectively) and arterial switch patients (p < 0.0001 and p < 0.001 respectively). In non-systemic ventricles, arterial switch patients had increased direct flow and decreased delayed ejection fractions compared to normal (p = 0.007 and p < 0.001 respectively) and atrial switch patients (p = 0.01 and p < 0.001 respectively). Regions of high levels of mixing of ventricular flow components showed elevated EL_v.

Conclusions

4D-flow MRI pathline tracking reveals disordered ventricular flow patterns and associated EL_v in d-TGA patients.

Key Points

• 4D-flow MRI can be used to assess intraventricular flow dynamics in d-TGA patients.

• d-TGA arterial switch patients mostly show intraventricular flow dynamics representative of normal subjects, while atrial switch patients show increased flow disorder and different proportions of intraventricular flow volumes.

• Flow disruption and disorder increase viscous energy losses.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-07813-0.