Tetralogy of Fallot

Recent advances in multimodal imaging in tetralogy of fallot and double outlet right ventricle

PURPOSE OF REVIEW

In the ever-evolving field of medical imaging, this review highlights significant advancements in preoperative and postoperative imaging for Tetralogy of Fallot (TOF) and double outlet right ventricle (DORV) over the past 18 months.

RECENT FINDINGS

This review showcases innovations in echocardiography such as 3D speckle tracking echocardiography (3DSTE) for assessing right ventricle-pulmonary artery coupling (RVPAC) and Doppler velocity reconstruction (DoVeR) for intracardiac flow fields evaluation. Furthermore, advances in assessment of cardiovascular anatomy using computed tomography (CT) improve the integration of imaging in ablation procedures. Additionally, the inclusion of cardiac magnetic resonance (CMR) parameters as risk score predictors for morbidity, and mortality and for timing of pulmonary valve replacement (PVR) indicates its significance in clinical management. The utilization of 4D flow techniques for postoperative hemodynamic assessment promises new insights into pressure mapping. Lastly, emerging technologies such as 3D printing and 3D virtual reality are expected to improve image quality and surgical confidence in preoperative planning.

SUMMARY

Developments in multimodality imaging in TOF and DORV are poised to shape the future of clinical practice in this field.

Cyanotic Congenital Heart Disease in Pregnancy: A Review of Pathophysiology and Management

The advancement of medical treatment and surgical technique, along with the invention of cardiopulmonary bypass, has allowed for long-term survival of patients with cyanotic congenital heart disease (CHD)-with many women with CHD now reaching child-bearing age and wishing to become pregnant. Pregnancy in these women is a major concern as the physiologic adaptations of pregnancy, including an increased circulating volume, increased cardiac output, reduced systemic vascular resistance, and decreased blood pressure, place a substantial load on the cardiovascular system. These changes are essential to meet the increased maternal and fetal metabolic demands and allow for sufficient placental circulation during gestation. However, in women with underlying structural heart conditions, they place an additional hemodynamic burden on the maternal body. Overall, with appropriate risk stratification, pre-conception counseling, and management by specialized cardiologists and high-risk obstetricians, most women with surgically corrected CHDs are expected to carry healthy pregnancies to term with optimization of both maternal and fetal risks. In this article, we describe the current understanding of 5 cyanotic CHDs-Tetralogy of Fallot, Transposition of the Great Arteries, Truncus Arteriosus, Ebstein's Anomaly, and Eisenmenger Syndrome-and explore the specific hemodynamic consequences, maternal and fetal risks, current guidelines, and outcomes of pregnancy in women with these conditions.

Transcatheter-Based Interventions for Tetralogy of Fallot Across All Age Groups

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Palliative procedures, either surgical or transcatheter, aim to improve oxygen saturation, affording definitive procedures at a later stage. Transcatheter interventions have been used before and after surgical palliative or definitive repair in children and adults. This review aims to provide an overview of the different catheter-based interventions for TOF across all age groups, with an emphasis on palliative interventions, such as patent arterial duct stenting, right ventricular outflow tract stenting, or balloon pulmonary valvuloplasty in infants and children and transcatheter pulmonary valve replacement in adults with repaired TOF, including the available options for a large, dilated native right ventricular outflow tract.

Determinants and Clinical Outcomes of Patients With Tetralogy of Fallot Lost to Cardiology Follow-up

BACKGROUND

Various rates of loss to follow-up (LTFU) have been reported in patients with congenital heart disease, but return to follow-up is rarely considered in those analyses. Outcomes of LTFU patients are difficult to assess because the patients no longer attend cardiac care. We leveraged data from the TRIVIA cohort, which combines more than 30 years of clinical and administrative data, allowing us to study outcomes even after LTFU.

METHODS

This population-based cohort included 904 patients with tetralogy of Fallot (TOF) born from 1982 to 2015 in Québec, Canada. Risk factors for LTFU and outcomes were calculated by Cox models and marginal means/rates models. Outcomes of LTFU patients were compared with propensity score-matched non-LTFU patients.

RESULTS

The cumulative risk of experiencing 1 episode of LTFU was 50.3% at 30 years. However, return to follow-up was frequent and the proportion of patients actively followed was 85.9% at 10 years, 76.4% at 20 years, and 70.6% at 30 years. Factors associated with a reduced risk of LTFU were primary repair with conduit (hazard ratio [HR] 0.29, 95% confidence interval [CI] 0.15-0.58) and transannular patch (HR 0.60, 95% CI 0.46-0.79). LTFU patients had lower rates of cardiac hospitalisations (HR 0.49, 95% CI 0.42-0.56) and cardiac interventions (HR 0.32, 95% CI 0.25-0.42), but similar rates of cardiac mortality (HR 0.95, 95% CI 0.24-3.80).

CONCLUSIONS

There was a lower proportion of LTFU patients compared with previous studies. Factors associated with lower rates of LTFU were conduits and non-valve-sparing surgery. LTFU patients had lower rates of cardiac procedures and cardiac hospitalisations.

Hemodynamic-based virtual surgery design of double-patch repair for pulmonary arterioplasty in tetralogy of Fallot

BACKGROUND AND OBJECTIVE

Surgical correction of pulmonary artery stenosis (PAS) is essential to the prognosis of patients with tetralogy of Fallot (TOF). The double-patch method of pulmonary arterioplasty is usually applied in case of multiple stenosis in TOF patients' pulmonary artery (PA) and when PAS cannot be relieved by the single-patch method. The surgical planning for the double-patch design remains challenging. The purpose of this study is to investigate the double-patch design with different angulations between the left pulmonary artery (LPA) and the right pulmonary artery (RPA), and to understand postoperative hemodynamic alterations by the application of computer-aided design (CAD) and computational fluid dynamics (CFD) techniques.

METHODS

The three-dimensional model of the PA was reconstructed based on preoperative computed tomography imaging data obtained from the patient with TOF. Three postoperative models with different designs of double-patch were created by "virtual surgery" using the CAD technique. Double-Patch 120 Model was created with double patches implanted in the main pulmonary artery (MPA) and the PA bifurcation and without changing the spatial position of PA. The angulation between the LPA and the RPA was defined as θ, which equaled to 120° in Pre-Operative Model and Double-Patch 120 Model. Based on Double-Patch 120 Model, Double-Patch 110 Model and Double-Patch 130 Model were generated with θ equaled to 110° and 130°, respectively. Combined with CFD, the differences of velocity streamlines, wall shear stress (WSS), flow distribution ratio (FDR), and energy loss (EL) were compared to analyze postoperative pulmonary flow characteristics.

RESULTS

The values of velocity and WSS decreased significantly after virtual surgery. Obvious vortices and swirling flows were observed downstream of the stenosis of RPA and LPA in Pre-Operative Model, while fewer vortices developed along the anterior wall of the expanded lumens of RPA, especially in Double-Patch 110 Model. With the relief of PAS, two relatively higher WSS regions were observed at the posterior walls of RPA and LPA. The maximum WSS values in these regions of Double-Patch 110 Model were lower than those in Double-Patch 120 Model and Double-Patch 130 Model. Furthermore, the FDRs were elevated and the ELs were greatly reduced. It was found that Double-Patch 110 Model with the angulation between the LPA and the RPA equaled to 110° showed relatively better properties of hemodynamics than other models.

CONCLUSIONS

The angulation between the LPA and the RPA is an important factor that should be integrated in the double-patch design for TOF repair. Virtual surgery based on patient-specific vascular model and computational hemodynamics can be used to provide assistance for individualized surgical planning of double-patch arterioplasty.

Late Diagnosis of Residual Major Aortopulmonary Collateral in a Patient with Tetralogy of Fallot

•Residual MAPCAs result in post-tricuspid shunt and PH. •Distinction between PH and conduit stenosis requires attention to TTE findings. •Management of complex adult CHD should be reserved for centers with expertise. •A multimodal imaging approach is often required to complete this understanding.

Successful Stent Implantation Into the Patent Ductus Arteriosus in Complex Cyanotic Congenital Heart Disease

Birth-associated structural issues with the heart are known as congenital heart disorders or defects. They might alter the heart's regular blood flow. A 10-month-old female child presented to a tertiary care hospital with symptoms of recurrent cyanotic spells with episodes of desaturation a few months after birth. ECG findings depicted a normal sinus rhythm with a right axis deviation along the right ventricular forces. Two-dimensional echocardiography showed a tetralogy of Fallot with pulmonary atresia with a patent ductus arteriosus from the undersurface of the arch with confluent small pulmonary arteries. A coronary wire was passed through the left subclavian artery, and a 4 × 16 mm stent was deployed successfully. After the procedure, the patient's saturation improved, and she was extubated on the table. The patient was on heparin for 24 hours and was started on oral aspirin thereafter. This case was discharged on the third postoperative day and was advised to follow up.

Predictors of Atrial Arrhythmia in Adults with Repaired Tetralogy of Fallot

Tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease in adults, has excellent long-term survival. However, many patients (30-45%) develop late arrhythmias. Previous studies have identified predictors of arrhythmia (atrial or ventricular) using clinical markers that predate arrhythmia onset by many years. Our objective was to develop a predictive model for incident atrial arrhythmias within two years of clinical evaluation and diagnostic testing. A single-center nested unmatched case-control study of 174 adults with repaired TOF. We included only patients with results from ECG and echocardiogram data in the required time interval (3-24 months before first arrhythmia for cases; 24 months of follow-up for controls). A predictive multivariable model for risk of incident atrial arrhythmia was developed using logistic regression with a least absolute shrinkage and selection operator (LASSO). Of 41 demographic, surgical, and diagnostic variables, six were selected as having predictive value for atrial arrhythmia based on cross validation. The factors with the greatest predictive value in decreasing order were moderate / severe tricuspid regurgitation (adjusted odds ratio (OR) 149.42), QRS fragmentation (OR 28.08), severe pulmonary regurgitation (OR 8.22), RV systolic dysfunction (OR 2.95), 1st degree AV block (OR 2.59), and age at time of surgical repair (OR 1.02). Predictors for atrial arrhythmia in our study suggested abnormal right ventricle anatomical function and electrophysiologic properties (conduction and repolarization) as the primary underlying substrate.

Adherence to clinical practice guidelines for pulmonary valve intervention after tetralogy of Fallot repair: A nationwide cohort study

Objectives

To determine guideline adherence pertaining to pulmonary valve replacement (PVR) referral after tetralogy of Fallot (TOF) repair.

Methods

Children and adults with cardiovascular magnetic resonance imaging scans and at least moderate pulmonary regurgitation were prospectively enrolled in the Comprehensive Outcomes Registry Late After TOF Repair (CORRELATE). Individuals with previous PVR were excluded. Patients were classified according to presence (+) versus absence (-) of PVR and presence (+) versus absence (-) of contemporaneous guideline satisfaction. A validated score (specific activity scale [SAS]) classified adult symptom status.

Results

In total, 498 participants (57% male, mean age 32 ± 14 years) were enrolled from 14 Canadian centers (2013-2020). Mean follow-up was 3.8 ± 1.8 years. Guideline criteria for PVR were satisfied for the majority (n = 422/498, 85%), although referral for PVR occurred only in a minority (n = 167/498, 34%). At PVR referral, most were asymptomatic (75% in SAS class 1). One participant (0.6%) received PVR without meeting criteria (PVR+/indication-). The remainder (n = 75/498, 15%) did not meet criteria for and did not receive PVR (PVR-/indication-). Abnormal cardiovascular imaging was the most commonly cited indication for PVR (n = 61/123, 50%). The SAS class and ratio of right to left end-diastolic volumes were independent predictors of PVR in a multivariable analysis (hazard ratio, 3.33; 95% confidence interval, 1.92-5.8, P < .0001; hazard ratio, 2.78; 95% confidence interval, 2.18-3.55, P < .0001).

Conclusions

Although a majority of patients met guideline criteria for PVR, only a minority were referred for intervention. Abnormal cardiovascular imaging was the most common indication for referral. Further research will be necessary to establish the longer-term clinical impact of varying PVR referral strategies.

Adult Congenital Heart Disease in the Emergency Department

While congenital heart disease historically was a pathology primarily restricted to specialized pediatric centers, advances in technology have dramatically increased the number of people living into adulthood, the number of complications faced by these patients, and the number of patients visiting non-specialized emergency departments for these concerns. Clinicians need to be aware of the issues specific to patients' individual congenital defects but also have an understanding of how typical cardiac pathology may manifest in this special group of patients. This manuscript attempts to provide an overview of this diverse but increasingly common group of adult patients with congenital heart diseases, including a review of their anatomical variants, the complications they face at the highest rates, and ways that emergency physicians may need to manage these patients differently to avoid causing harm.

Meta-analysis reveals differential gene expression in tetralogy of Fallot versus controls

OBJECTIVES

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect in the United States. We aimed to identify genetic variations associated with TOF using meta-analysis of publicly available digital samples to spotlight targets for prevention, screening, and treatment strategies.

METHODS

We used the Search Tag Analyze Resource for Gene Expression Omnibus (STARGEO) platform to identify 39 TOF and 19 non-TOF right ventricle tissue samples from microarray data and identified upregulated and downregulated genes. Associated gene expression data were analyzed using ingenuity pathway analysis and restricted to genes with a statistically significant (p < .05) difference and an absolute experimental log ratio >0.1 between disease and control samples.

RESULTS

Our analysis identified 220 genes whose expression profiles were significantly altered in TOF vs. non-TOF samples. The most striking differences identified in gene expression included genes FBXO32, PTGES, MYL12a, and NR2F2. Some top associated canonical pathways included adrenergic signaling, estrogen receptor signaling, and the role of NFAT in cardiac hypertrophy. In general, genes involved in adaptive, defensive, and reparative cardiovascular responses showed altered expression in TOF vs. non-TOF samples.

CONCLUSIONS

We introduced the interpretation of open "big data" using the STARGEO platform to define robust genomic signatures of congenital heart disease pathology of TOF. Overall, our meta-analysis results indicated increased metabolism, inflammation, and altered gene expression in TOF patients. Estrogen receptor signaling and the role of NFAT in cardiac hypertrophy represent unique pathways upregulated in TOF patients and are potential targets for future pharmacologic treatments.

How best can we name the channels seen in the setting of deficient ventricular septation?

Surgical repair of channels between the ventricles is enhanced when the surgeon knows precisely where to place a patch, or baffle, so as to restore septal integrity. The paediatric cardiologist should provide the necessary information. Communication will be enhanced if the same words are used to account for the structures in question. Currently, however, the same term, namely "ventricular septal defect," is used to account for markedly different areas within the heart. Closure of perimembranous defects found in hearts with concordant or discordant ventriculo-arterial connections restores the integrity of the ventricular septum, at the same time separating the systemic and pulmonary blood streams. When both arterial trunks arise from the right ventricle, in contrast, the surgeon when placing a baffle so as to separate the blood streams, does not close the channel most frequently described as the "ventricular septal defect." In this review, we show that the perimembranous lesions as found in hearts with concordant or discordant ventriculo-arterial connections are the right ventricular entrances to the areas subtended beneath the hinges of the leaflets of the aortic or pulmonary valves. When both arterial trunks arise from the right ventricle, and the channel between the ventricles is directly subaortic, then the channel termed the "ventricular septal defect" is the left ventricular entrance to the comparable space subtended beneath the aortic root. We argue that recognition of these fundamental anatomical differences enhances the appreciation of the underlying morphology of the various lesions that reflect transfer, during cardiac development, of the aortic root from the morphologically right to the morphologically left ventricle.

Comparison between the modified Blalock-Taussig shunt and right ventricular outflow tract stent in the palliative treatment for tetralogy of Fallot

OBJECTIVES

For patients with tetralogy of Fallot (TOF) who are not suitable candidates for primary corrective surgery or have a high surgical risk, transcatheter right ventricular outflow tract (RVOT) stent implantation is considered a safe and effective palliative intervention. This study aims to investigate the therapeutic outcomes of RVOT stent implantation in neonates and infants with TOF in comparison with the modified Blalock-Taussig shunt (mBTS) and to compare the impact of the 2 palliative interventions on arterial oxygen saturation and pulmonary artery development in pediatric patients.

METHODS

Clinical data of 32 patients with TOF admitted to the Second Xiangya Hospital of Central South University from March 2011 to March 2021 were retrospectively collected. The patients were divided into an mBTS group (undergoing mBTS, n=15) and a stent implantation group (undergoing RVOT stenting, n=17) according to the surgical procedures. The 2 groups were assessed and compared in the surgical-related arterial oxygen saturation, postoperative complication rate, mortality rate, and re-intervention rate. The development of the patients' main pulmonary artery, right pulmonary artery, and left pulmonary artery was assessed by z-scores according to echocardiographic results.

RESULTS

The children in the stent implantation group were younger and less weighed compared with the mBTS group (both P<0.05). Compared with the preoperative period, children in the stent implantation group had significantly higher arterial oxygen saturation [(75±17)% vs (96±3)%, P=0.026]; z-scores of pulmonary trunk [(-2.82±1.27) points vs (0.86±0.77) points, P=0.014], right pulmonary artery [(-1.88±0.59) points vs (-0.28±0.71) points, P=0.011], and left pulmonary artery [(-2.34±0.36) points vs (-1.67±0.36) points, P=0.036] were significantly increased. However, there were no significant differences in arterial oxygen saturation and pulmonary artery z-scores between pre- and post-mBTS procedures (all P>0.05).

CONCLUSIONS

RVOT stent would have good surgical outcomes used in TOF patients with low weight and severe comorbidities. It also leads to an higher postoperative oxygen saturation and better promotion of pulmonary artery growth with RVOT stent compared to mBTS.

Rehabilitation in a Pediatric Patient Who Underwent Correction Surgery for Tetralogy of Fallot: A Case Report

Tetralogy of Fallot (TOF) is a congenital heart defect characterized by four distinct heart abnormalities, which include an overriding aorta (where the aorta crosses both ventricles), a ventricular septal defect (VSD), right ventricular hypertrophy (the right ventricle muscle is thickened), and pulmonary stenosis (the pulmonary valve and artery are narrowed). Individuals suffering from TOF may exhibit pinkness, cyanosis at baseline, or episodes of hypercyanosis. The pathoanatomy of the TOF allows blood from the pulmonary and systemic circulations to mix. Cyanosis is caused by the addition of deoxygenated blood from a shunt that runs from right to left to the systemic circulation. In this case report, we present a five-year-old female patient with a known case of TOF. The results were recorded using the Pediatric Quality of Life (PedsQL) Questionnaire, New York Heart Association (NYHA) Dyspnoea Scale, Wong-Baker Faces Pain Rating Scale, and arterial blood gas analysis. Therapy goals were to improve overall functional ability, to remove secretions from airway, and the return of acceptable cardiovascular function. This case report focuses on the success of the cardiorespiratory rehabilitation program based on the patient's current state of health. The outcome parameters confirm that patients can experience improved functional recovery.

Pulmonary Artery Stenosis in Tetralogy of Fallot

Tetralogy of Fallot (TOF) is the most common cyanotic congenital cardiac defect. The survival rate after primary complete repair is high (98-100%); however, pulmonary artery stenosis (PAS) is not uncommon after TOF repair, and severe PAS aggravates pulmonary regurgitation, resulting in right ventricle dilation, ventricular arrhythmia, and possibly death. PAS in TOF can be congenital due to hypoplasia or coarctation or can be acquired secondary to a surgical procedure. The latter may be caused by an exogenous conduit implant, compression from the adjacent enlarged ascending aorta, or outflow tract dilation after transannular patch repair. PAS can also be caused by the pulmonary artery plasty strategy itself. Here, the intrinsic mechanisms underlying PAS and pulmonary artery plasty techniques and strategies are reviewed to provide guidance for surgeons.

Dichorionic Diamniotic Twin Pairs with Complex Congenital Heart Disease

Complex congenital heart disease (CHD) in each of dichorionic diamniotic (DiDi) twin pairs is extremely rare and has not been well characterized. Four DiDi twin pairs were included in this multi-institutional case series. The congenital cardiac abnormalities noted included tetralogy of Fallot (ToF) with pulmonary atresia and collaterals (n = 1), ToF with absent pulmonary valve (n = 1), ToF (n = 2), discontinuous right pulmonary artery (RPA) (n = 1), tricuspid atresia (TA) with normally related great arteries and pulmonary valve stenosis or atresia (n = 2) and coarctation of aorta (CoA) with bicuspid aortic valve (BAV) and borderline left-sided structures (n = 1). Genetic testing was obtained on seven of the eight twins but did not reveal any causal abnormality. A comprehensive review of literature yielded another 8 DiDi twin pairs with complex CHD. The CHD noted in these twin pairs included ToF (n = 2), CoA (n = 4), corrected transposition of great arteries (ccTGA) (n = 2), truncus arteriosus (n = 2), complete common atrioventricular canal (CCAVC) (n = 2), hypoplastic left heart syndrome (HLHS) (n = 2), Shone's complex (n = 1), and hypoplastic right heart syndrome (HRHS) (n = 1). Limited genetic testing was obtained on 4 of these twins and revealed trisomy 21 in a twin pair. Conotruncal abnormalities (42%), CoA (21%), and abnormalities of the right ventricle, the right ventricular outflow tract and pulmonary arteries (17%) are more prevalent in DiDi twins with complex CHD. Clustering of these abnormalities suggests a possible genetic basis; however, genetic testing was obtained on eleven of the twins, and except for trisomy 21 in a twin pair both of whom had CCAVC, did not reveal any causal abnormality. A major direct genetic contribution is therefore unlikely and like other CHD, the underlying etiopathological basis is likely multifactorial.

Short-term outcomes following total correction of tetralogy of fallot in adult patients

OBJECTIVES

Tetralogy of Fallot (TOF) is a common congenital heart disease which should be corrected. The recommended time for the Tetralogy of Fallot Total Correction (TFTC) surgery is during the infancy for the possible difficulties during the surgery and the related issues. However, sometimes TOF is diagnosed and managed during the adulthood.

METHODS

This study is a descriptive and retrospective one which included all patients who underwent TFTC at the age of 15-year and older in 10 years (between the years 2010 and 2020) to identify short-term (in-hospital mortality, ICU stay, postoperative bleeding, respiratory complications after the surgery such as pulmonary edema, pneumonia, etc.) and one-year (left ventricle ejection fraction (LVEF), right ventricle (RV) ejection fraction, the severity of tricuspid and aortic regurgitation after surgery) outcomes. All data were taken from medical records at Rajaie Cardiovascular Medical and Research Center. Data were analyzed using SPSS 22.

RESULTS

94 patients with the mean ± SD age of 26.7 ± 9.6 years were enrolled. Most of them were male (59.6%) (P-value: 0.009). In-hospital mortality in our study were 5.3%. Tricuspid regurgitation (TR) was significantly resolved after the surgery (P-value: 0.006). Of 17 (18.1%) patients with small or hypoplastic pulmonary artery (PA) branches, 14 patients had acceptable PA branch size after surgery.

CONCLUSION

TFTC at an older age is safe with acceptable results. Age is not a contraindication for TFTC and surgery should be recommended if the patients are diagnosed with TOF in adulthood. Also, the TOF diagnosis should be considered in adult patients with suspicious signs and symptoms.

Unrepaired tetralogy of Fallot in a 71 years old woman: A case report and review of the literature

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease (CHD) in infants. The four components that constitute ToF are an overriding aorta over the crest of the interventricular septum, obstruction in the right ventricular outflow tract, right ventricular hypertrophy, and a typically large non-restricted ventricular septal defect. ToF may also be associated with other extracardiac abnormalities, including patent ductus arteriosus or multiple aortopulmonary collateral arteries, which can impact the patient's survival. Patients with unoperated ToF rarely reach adulthood, and it is extremely rare to discover undiagnosed ToF in individuals over 60 years old. In this report, we describe an unusual case of a woman with unrepaired ToF who survived until the age of 71. She was fairly asymptomatic until the 7th decade of her life and complained only of dyspnea on exertion. The patient declined corrective cardiac surgery and preferred conservative management.

Multimodality Imaging Assessment of Tetralogy of Fallot: From Diagnosis to Long-Term Follow-Up

Tetralogy of Fallot (TOF) is the most common complex congenital heart disease with long-term survivors, demanding serial monitoring of the possible complications that can be encountered from the diagnosis to long-term follow-up. Cardiovascular imaging is key in the diagnosis and serial assessment of TOF patients, guiding patients' management and providing prognostic information. Thorough knowledge of the pathophysiology and expected sequalae in TOF, as well as the advantages and limitations of different non-invasive imaging modalities that can be used for diagnosis and follow-up, is the key to ensuring optimal management of patients with TOF. The aim of this manuscript is to provide a comprehensive overview of the role of each modality and common protocols used in clinical practice in the assessment of TOF patients.

Abnormal developmental trajectory and vulnerability to cardiac arrhythmias in tetralogy of Fallot with DiGeorge syndrome

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Ventricular dysfunction and cardiac arrhythmias are well-documented complications in patients with repaired TOF. Whether intrinsic abnormalities exist in TOF cardiomyocytes is unknown. We establish human induced pluripotent stem cells (hiPSCs) from TOF patients with and without DiGeorge (DG) syndrome, the latter being the most commonly associated syndromal association of TOF. TOF-DG hiPSC-derived cardiomyocytes (hiPSC-CMs) show impaired ventricular specification, downregulated cardiac gene expression and upregulated neural gene expression. Transcriptomic profiling of the in vitro cardiac progenitors reveals early bifurcation, as marked by ectopic RGS13 expression, in the trajectory of TOF-DG-hiPSC cardiac differentiation. Functional assessments further reveal increased arrhythmogenicity in TOF-DG-hiPSC-CMs. These findings are found only in the TOF-DG but not TOF-with no DG (ND) patient-derived hiPSC-CMs and cardiac progenitors (CPs), which have implications on the worse clinical outcomes of TOF-DG patients.

Artificial intelligence-based approaches for the detection and prioritization of genomic mutations in congenital surgical diseases

Genetic mutations are critical factors leading to congenital surgical diseases and can be identified through genomic analysis. Early and accurate identification of genetic mutations underlying these conditions is vital for clinical diagnosis and effective treatment. In recent years, artificial intelligence (AI) has been widely applied for analyzing genomic data in various clinical settings, including congenital surgical diseases. This review paper summarizes current state-of-the-art AI-based approaches used in genomic analysis and highlighted some successful applications that deepen our understanding of the etiology of several congenital surgical diseases. We focus on the AI methods designed for the detection of different variant types and the prioritization of deleterious variants located in different genomic regions, aiming to uncover susceptibility genomic mutations contributed to congenital surgical disorders.

Valvular Regurgitation in Adults with Congenital Heart Disease and Heart Failure: Current Status and Potential Interventions

The great majority of patients born with congenital heart disease (CHD) are living well into adulthood, yet they often have residual hemodynamic lesions, including valvar regurgitation. As these complex patients grow older, they are at risk of developing heart failure, which can be exacerbated by the underlying valvular regurgitation. In this review, we describe the etiologies of heart failure related to valvular regurgitation in the CHD population and discuss potential interventions.

Management of tetralogy of Fallot in the pediatric intensive care unit

Tetralogy of Fallot (ToF) is one of the most common congenital cyanotic heart lesions and can present to a variety of health care professionals, including teams working in pediatric intensive care. Pediatric intensive care teams may care for a child with ToF pre-operatively, peri-operatively, and post-operatively. Each stage of management presents its own unique challenges. In this paper we discuss the role of pediatric intensive care in each stage of management.

Perioperative Management of Emergency Craniotomes in Children With Cyanotic Congenital Heart Disease: A Case Series

While congenital heart disease is not uncommon, cyanotic congenital heart disease (CCHD) accounts for a minor fraction of them. However, when cyanosis is present, it usually indicates a severe or critical illness. Tetralogy of Fallot (TOF) is one of the common CCHDs, representing 7-10% of all congenital cardiac malformations. Double-outlet right ventricle (DORV) is another CCHD similar to the TOF and associated with decreased pulmonary flow, ventricular septal defect (VSD), and aorta receiving blood from both ventricles. Reduced oxygen arterial saturation and increased viscosity by polycythemia induce focal cerebral ischemia, often in the area supplied by the middle cerebral artery leading to brain abscess. Brain abscesses require craniotomy, which is a major surgery. These patients also often show features of sepsis and increased intracranial pressure. The presence of CCHD further complicates the situation, making perioperative management even more challenging. There are studies in the literature on the management of similar cases, and they report successful management in most of them. However, not all such cases need intensive postoperative management. We present four pediatric cases who had either TOF or DORV and had to undergo craniotomy for brain abscess or ventriculoperitoneal shunt placement. We describe case management and highlight the critical features and cases that require prolonged postoperative critical care management.

Paucisymptomatic Tetralogy of Fallot diagnosed in a 56-year-old patient: a case report

BACKGROUND

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. It is generally diagnosed and surgically repaired early in life, with good overall outcomes.

CASE PRESENTATION

We report the case of a patient incidentally diagnosed with paucisymptomatic TOF at the age of 56 years old, during investigations for carbon monoxide poisoning. The patient had a history of thyroidectomy, arterial hypertension, and four uncomplicated vaginal deliveries.

CONCLUSIONS

This case shows us that some patients with TOF can reach older ages without surgical correction. Late surgical repair should be meticulously decided on a case basis.

Serial Magnetic Resonance Imaging for Aortic Dilation in Tetralogy of Fallot With Pulmonary Stenosis

Aortic dilation occurs in patients with repaired tetralogy of Fallot (TOF), but the rate of growth is incompletely characterized. The aim of this study was to assess the rates of growth of the aortic root and ascending aorta in a cohort of pediatric and adult patients with sequential magnetic resonance angiography Magnetic Resonance Imaging (MRI) data. Using serial MRI data from pediatric and adult patients with repaired TOF, we performed a retrospective analysis of the rates of growth and associations with growth of the aortic root and ascending aorta. Patients with pulmonary atresia or absent pulmonary valve were excluded. Between years 2005 to 2021, a total of 99 patients were enrolled. A follow-up MRI was performed an average of 5.9 ± 3.7 years from the initial study. For the cohort aged ≥16 years, the mean rate of change in diameter was 0.2 ± 0.5 mm/year at the ascending aorta and 0.2 ± 0.6 mm/year at the sinus of Valsalva. For the entire cohort, the mean change in cross-sectional area indexed to height at the ascending aorta was 7 ± 12 mm2/m/year and at the sinus of Valsalva was 10 ± 16 mm2/m/year. Younger age was associated with higher rates of growth of the sinus of Valsalva while the use of β blockers or angiotensin-converting enzyme inhibitors was associated with a slower rate of growth. There were no cases of aortic dissection in this cohort. We conclude that serial MRI demonstrates a slow rate of growth of the aorta in the TOF.

Recurrent Hemoptysis in an Adult Patient With an Unfamiliar Cause

Most adult patients who experience recurrent hemoptysis have respiratory or coagulopathy-related causes and cardiac aetiology in very few cases. In this rare case of 56 years aged male patient who presented to us with chronic recurrent hemoptysis, Tetralogy of Fallot (TOF) was the culprit aetiology, and he was successfully managed by minimal intervention.

Electroencephalographic changes in neurologically free patients with tetralogy of Fallot after surgical repair: a cross section study in Egyptian children

Background

Surgical correction of tetralogy of Fallot (TOF) is still one of the most frequently performed intervention in pediatric cardiac surgery. The occurrence of seizures after repair or palliation of congenital heart disease (CHD) is a marker for a central nervous system (CNS) injury and has been associated with adverse neurodevelopmental sequelae. The prognostic value of electroencephalogram (EEG) for outcome prediction is glowing in children with CHD undergoing open-heart surgery who are at risk for subsequent neurodevelopmental deficits. To our knowledge, this is the first study to detect the EEG changes in neurologically free TOF patients after surgical repair

Results

Our study included 68 TOF cases and 32 sex- and age-matched control group; they were 66.0% males and 34.0% females. The mean age of the studied children was 11.41 ± 4.23 years. There was statistically significant difference between TOF patients and control group as regards alpha power and Delta% in left occipital region and Alpha% in right occipital region, with dominant alpha waves in patients’ right occipital region. None of our patients had epileptic waves. The duration after operation showed negative correlation with Delta% at left occipital region and positive correlation with Alpha% in right occipital region (p = 0.002, p = 0.044 respectively).

Conclusion

TOF cases showed changes in EEG parameters chiefly dominant alpha power and Delta% in left occipital region and dominant Alpha% in right occipital region. Duration after surgery correlated negatively with Delta% at left occipital region, and positively with Alpha% in the right occipital region. Subsequent assessment is recommended to study long-term hazards of these varied dominance of EEG waves in our patients, e.g., evaluation of the cognitive functions.

The predictive role of right ventricular late gadolinium enhancement in patients with tetralogy of Fallot undergoing pulmonary valve replacement

BACKGROUND

Our purpose was to evaluate the correlations between right ventricular (RV) late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) in patients with tetralogy of Fallot (ToF) scheduled for pulmonary valve replacement (PVR) and post-PVR functional data.

METHODS

We retrospectively reviewed ToF patients scheduled for PVR who underwent two CMR examinations at our institution, one before the procedure (CMR-0), including contrast-enhanced sequences, and one after the procedure (CMR-1). Functional left and RV data were obtained by segmenting short-axis stacks on both CMR examinations, and normalised variations were calculated by dividing differences between CMR-1 and CMR-0 by the intercurring time interval, whereas the RV scar burden was assessed on CMR-0 LGE sequences both semiquantitatively and quantitatively. Data were reported as median and interquartile range, differences were appraised with the Mann-Whitney U test, while correlations were assessed with Spearman's ρ.

RESULTS

Fifteen patients with a median age of 25 years (16-29), including 9 (60%) males, with a median time interval between CMR-0 and CMR-1 of 17 months (12-23), were retrospectively reviewed. The semiquantitative LGE score at CMR-0 was 7 (6-9), and LGE volume was 4.49 mL (3.70-5.78), covering 5.63% (4.92-7.00) of the RV. RV LGE score showed a moderate positive correlation with the normalised variation of RV stroke volume (ρ = 0.662, p = 0.007) and a borderline moderate positive correlation with the normalised variation of RV end-diastolic indexed volume (ρ = 0.513, p = 0.050).

CONCLUSIONS

The assessment of RV LGE before PVR may provide insights on post-PVR functional data, potentially facilitating a patient-tailored treatment pathway.

Biventricular shape modes discriminate pulmonary valve replacement in tetralogy of Fallot better than imaging indices

Current indications for pulmonary valve replacement (PVR) in repaired tetralogy of Fallot (rTOF) rely on cardiovascular magnetic resonance (CMR) image-based indices but are inconsistently applied, lead to mixed outcomes, and remain debated. This study aimed to test the hypothesis that specific markers of biventricular shape may discriminate differences between rTOF patients who did and did not require subsequent PVR better than standard imaging indices. In this cross-sectional retrospective study, biventricular shape models were customized to CMR images from 84 rTOF patients. A statistical atlas of end-diastolic shape was constructed using principal component analysis. Multivariate regression was used to quantify shape mode and imaging index associations with subsequent intervention status (PVR, n = 48 vs. No-PVR, n = 36), while accounting for confounders. Clustering analysis was used to test the ability of the most significant shape modes and imaging indices to discriminate PVR status as evaluated by a Matthews correlation coefficient (MCC). Geometric strain analysis was also conducted to assess shape mode associations with systolic function. PVR status correlated significantly with shape modes associated with right ventricular (RV) apical dilation and left ventricular (LV) dilation (p < 0.01), RV basal bulging and LV conicity (p < 0.05), and pulmonary valve dilation (p < 0.01). PVR status also correlated significantly with RV ejection fraction (p < 0.05) and correlated marginally with LV end-systolic volume index (p < 0.07). Shape modes discriminated subsequent PVR better than standard imaging indices (MCC = 0.49 and MCC = 0.28, respectively) and were significantly associated with RV and LV radial systolic strain. Biventricular shape modes discriminated differences between patients who did and did not require subsequent PVR better than standard imaging indices in current use. These regional features of cardiac morphology may provide insight into adaptive vs. maladaptive types of structural remodeling and point toward an improved quantitative, patient-specific assessment tool for clinical use.

The American Association for Thoracic Surgery (AATS) 2022 Expert Consensus Document: Management of infants and neonates with tetralogy of Fallot

OBJECTIVE

Despite decades of experience, aspects of the management of tetralogy of Fallot with pulmonary stenosis (TOF) remain controversial. Practitioners must consider newer, evolving treatment strategies with limited data to guide decision making. Therefore, the TOF Clinical Practice Standards Committee was commissioned by the American Association for Thoracic Surgery to provide a framework on this topic, focused on timing and types of interventions, management of high-risk patients, technical considerations during interventions, and best practices for assessment of outcomes of the interventions. In addition, the group was tasked with identifying pertinent research questions for future investigations. It is recognized that variability in institutional experience could influence the application of this framework to clinical practice.

METHODS

The TOF Clinical Practice Standards Committee is a multinational, multidisciplinary group of cardiologists and surgeons with expertise in TOF. With the assistance of a medical librarian, a citation search in PubMed, Embase, Scopus, and Web of Science was performed using key words related to TOF and its management; the search was restricted to the English language and the year 2000 or later. Articles pertaining to pulmonary atresia, absent pulmonary valve, atrioventricular septal defects, and adult patients with TOF were excluded, as well as nonprimary sources such as review articles. This yielded nearly 20,000 results, of which 163 were included. Greater consideration was given to more recent studies, larger studies, and those using comparison groups with randomization or propensity score matching. Expert consensus statements with class of recommendation and level of evidence were developed using a modified Delphi method, requiring 80% of the member votes with 75% agreement on each statement.

RESULTS

In asymptomatic infants, complete surgical correction between age 3 and 6 months is reasonable to reduce the length of stay, rate of adverse events, and need for a transannular patch. In the majority of symptomatic neonates, both palliation and primary complete surgical correction are useful treatment options. It is reasonable to consider those with low birth weight or prematurity, small or discontinuous pulmonary arteries, chromosomal anomalies, other congenital anomalies, or other comorbidities such as intracranial hemorrhage, sepsis, or other end-organ compromise as high-risk patients. In these high-risk patients, palliation may be preferred; and, in patients with amenable anatomy, catheter-based procedures may prove favorable over surgical palliation.

CONCLUSIONS

Ongoing research will provide further insight into the role of catheter-based interventions. For complete surgical correction, both transatrial and transventricular approaches are effective; however, the smallest possible ventriculotomy should be utilized. When possible, the pulmonary valve should be spared; and if unsalvageable, reconstruction can be considered. At the conclusion of the operation, adequate relief of the right ventricular outflow obstruction should be confirmed, and identification of a significant fixed anatomical obstruction should prompt further intervention. Given our current knowledge and the gaps identified, we propose several key questions to be answered by future research and potentially by a TOF registry: When to palliate or proceed with complete surgical correction, as well as the ideal type of palliation; the optimal surgical approach for complete repair for the best long-term preservation of right ventricular function; and the utility, efficacy, and durability of various pulmonary valve preservation and reconstruction techniques.

Realignment of the ventricular septum in tetralogy of Fallot using (partial) direct closure of the ventricular septal defect: Long-term follow-up and comparison to conventional patch repair

Objectives

Aortic dilatation and regurgitation after surgical repair of tetralogy of Fallot (TOF) is known, and beside other factors, mainly addressed to an intrinsic aortopathy. In 2011, we reported the influence of realingement of the left ventricular outflow tract (LVOT) by (partial) direct closure of the ventricular septal defect (VSD) in TOF on aortic structures and function. We now evaluated the further follow-up of this cohort and compared the results to a matched group of TOF patients with classical VSD patch closure.

Patients and Methods

Forty patients with TOF treated between 2003 and 2008 are included in the study, with 20 patients each in the VSD (a) (partial) direct closure and (b) patch closure group. Follow-up time after surgery was 12.3 years (11.3-13.0).

Results

Patient characteristics, echocardiographic measurements, and surgical and intensive care unit parameters were not significantly different between both groups. After surgery and during long-term follow-up, realignement of the LVOT, shown by the angle between the interventricular septum and the anterior aortic annulus in long axis view in echocardiography, was lower in Group A (34 vs. 45°, P < 0.0001). No differences in LVOT or aortic annulus size, aortic regurgitation, or dilation of the ascending aorta and right ventricular outflow tract gradients were found. Transient rhythm disturbances were found in 3 patients in each group, with only one persistent complete atrioventricular block in Group B.

Conclusion

(Partial) direct closure of the VSD in TOF leads to a better realignement of the LVOT and showed comparable short- and long-term results without higher risk for rhythm disturbances during follow-up.

Computed tomography in tetralogy of Fallot: pre- and postoperative imaging evaluation

Tetralogy of Fallot (TOF) is the most common cause of cyanotic congenital heart disease (CHD) and the most frequent complex CHD encountered in adulthood. Although children with TOF share four characteristic features (subaortic ventricular septal defect, overriding aorta, right ventricular hypertrophy, pulmonary stenosis), the clinical spectrum and course are in fact greatly heterogeneous. Echocardiography remains the mainstay for diagnosis, presurgical planning and postoperative follow-up. However, with continued technological advances, CT now plays an increasing role in TOF evaluation and management, helping to minimize routine invasive catheter angiography. Preoperatively, CT is uniquely suited to assess associated pulmonary arterial, aortic and coronary anomalies as well as extra-cardiovascular structures and is particularly helpful for delineating complex anatomy in the TOF subtypes of absent pulmonary valve and pulmonary atresia with major aortopulmonary collaterals. Postoperatively, CT is useful for identifying surgical complications and for long-term monitoring including volumetry quantification, especially in children for whom MRI is contraindicated or limited by implanted devices such as pacemakers and stents. In this article, we review key clinical features and considerations in the pre- and postoperative TOF patient and the burgeoning role of CT for facilitating accurate diagnosis and personalized intervention.

CMR parameters and CMR-FT in repaired tetralogy of Fallot

Background

Repaired tetralogy of Fallot patients develops postoperative complications that are in need for follow-up and re-intervention in some circumstances. CMR myocardial feature tracking is a novel method that allows quantification of bi-atrial and bi-ventricular mechanics of deformation. So our aim is to assess the added value of cardiac magnetic resonance imaging and its advanced feature tracking analysis in evaluation of repaired tetralogy of Fallot patients.

Results

CMR was done with feature tracking post-processing analysis for 56 patients with repaired tetralogy of Fallot and 56 healthy volunteers. The commonest postoperative complications in patients with repaired tetralogy of Fallot are in the following order: pulmonary regurgitation with subsequent right ventricular dilatation and tricuspid regurgitation followed by pulmonary stenosis, right ventricular dysfunction, right ventricular outflow tract dilatation, left ventricular dysfunction, aortic and mitral regurgitation and residual ventricular septal defect. All right ventricular volumes were found to be significantly increased compared to those of the healthy volunteers (p value < 0.001) also left ventricular end-diastolic and end-systolic volumes indexed were found to be increased in those patients compared to healthy volunteers (p value < 0.001). Right and left ventricular function were significantly lower in those patients compared to controls. Bi-ventricular CMR-FT indices and right atrial global longitudinal strain were found to be significantly lower in patients with repaired tetralogy of Fallot compared to controls. Right atrium global longitudinal strain was found to be significantly correlated with right ventricular global longitudinal strain and did not correlate with right ventricular ejection fraction and end-diastolic volume indexed; p value < 0.001, 0.109 and 0.565, respectively. Right ventricular global circumferential strain was found to be significantly increased in patients with right ventricular outflow tract obstruction compared to those without obstruction (− 16.26 ± 4.27% vs. − 12.2 ± 3.78%, respectively). Pulmonary regurgitant volume indexed was found to be significantly related to right ventricle longitudinal strain (p value 0.027).

Conclusion

Biventricular volumetric measures are increased in patients with repaired tetralogy of Fallot compared to controls; however, feature tracking parameters for both ventricles and right atrium are lower in those patients compared to controls.

Tetralogy of Fallot with double aortic arch and aortopulmonary window: a very rare trifecta

Tetralogy of Fallot with an aortopulmonary window and double aortic arch is very rare. This complex coexistence may be over a wide clinical spectrum. Herein, we present an asymptomatic 8-day-old infant who was diagnosed as having tetralogy of Fallot, double aortic arch, and an aortopulmonary window using transthoracic echocardiography while being examined for microcephaly.

Impact of Management Strategy on Feeding and Somatic Growth in Neonates with Symptomatic Tetralogy of Fallot: Results from the Congenital Cardiac Research Collaborative

OBJECTIVE

To evaluate early growth following primary or staged repair of neonatal symptomatic tetralogy of Fallot (sTOF).

STUDY DESIGN

We performed a retrospective, multicenter cohort study of consecutive infants with sTOF who underwent initial intervention at age ≤30 days, from 2005 to 2017. Management strategies were either primary repair or staged repair (ie, initial palliation followed by complete repair). The primary outcome was change in weight-for-age z-score (ΔWAZ) from the initial intervention to age 6 ± 2 months. Secondary outcomes included method and mode of feeding, feeding-related medications, and feeding-related readmissions. Propensity score adjustment was used to account for baseline differences between groups. A secondary analysis was performed comparing patients stratified by the presence of adequate growth (6-month ΔWAZ > -0.5) or inadequate growth (6-month ΔWAZ ≤ -0.5), independent of treatment strategy.

RESULTS

The study cohort included 143 primary repair subjects and 240 staged repair subjects. Prematurity was more common in the staged repair group. After adjustment, median ΔWAZ did not differ between treatment groups over the first 6 months of life (primary: -0.43 [IQR, -1.17 to 0.50]; staged: -0.31 [IQR, -1.31 to 0.71]; P = .55). For the entire cohort, ΔWAZ was negative (-0.36; IQR, -1.21 to 0.63). There were no between-group differences in the secondary outcomes. Secondary analysis revealed that the subjects with adequate growth were more likely to be orally fed at initial hospital discharge (P = .04).

CONCLUSIONS

In neonates with sTOF, growth trajectory over the first 6 months of life was substandard, irrespective of treatment strategy. Those patients with adequate growth were more likely to be discharged from the index procedure on oral feeds.

Genetic insights into non-syndromic Tetralogy of Fallot

Congenital heart defects (CHD) include structural abnormalities of the heart or/and great vessels that are present at birth. CHD affects around 1% of all newborns worldwide. Tetralogy of Fallot (TOF) is the most prevalent cyanotic congenital cardiac abnormality, affecting three out of every 10,000 live infants with a prevalence rate of 5-10% of all congenital cardiac defects. The four hallmark characteristics of TOF are: right ventricular hypertrophy, pulmonary stenosis, ventricular septal defect, and overriding aorta. Approximately 20% of cases of TOF are associated with a known disease or chromosomal abnormality, with the remaining 80% of TOF cases being non-syndromic, with no known aetiology. Relatively few TOF patients have been studied, and little is known about critical causative genes for non-syndromic TOF. However, rare genetic variants have been identified as significant risk factors for CHD, and are likely to cause some cases of TOF. Therefore, this review aims to provide an update on well-characterized genes and the most recent variants identified for non-syndromic TOF.

Joint analysis of functionally related genes yields further candidates associated with Tetralogy of Fallot

Although several genes involved in the development of Tetralogy of Fallot have been identified, no genetic diagnosis is available for the majority of patients. Low statistical power may have prevented the identification of further causative genes in gene-by-gene survey analyses. Thus, bigger samples and/or novel analytic approaches may be necessary. We studied if a joint analysis of groups of functionally related genes might be a useful alternative approach. Our reanalysis of whole-exome sequencing data identified 12 groups of genes that exceedingly contribute to the burden of Tetralogy of Fallot. Further analysis of those groups showed that genes with high-impact variants tend to interact with each other. Thus, our results strongly suggest that additional candidate genes may be found by studying the protein interaction network of known causative genes. Moreover, our results show that the joint analysis of functionally related genes can be a useful complementary approach to classical single-gene analyses.

Healing the Broken Hearts: A Glimpse on Next Generation Therapeutics

Cardiovascular diseases are the leading cause of death worldwide, accounting for 32% of deaths globally and thus representing almost 18 million people according to WHO. Myocardial infarction, the most prevalent adult cardiovascular pathology, affects over half a million people in the USA according to the last records of the AHA. However, not only adult cardiovascular diseases are the most frequent diseases in adulthood, but congenital heart diseases also affect 0.8–1.2% of all births, accounting for mild developmental defects such as atrial septal defects to life-threatening pathologies such as tetralogy of Fallot or permanent common trunk that, if not surgically corrected in early postnatal days, they are incompatible with life. Therefore, both congenital and adult cardiovascular diseases represent an enormous social and economic burden that invariably demands continuous efforts to understand the causes of such cardiovascular defects and develop innovative strategies to correct and/or palliate them. In the next paragraphs, we aim to briefly account for our current understanding of the cellular bases of both congenital and adult cardiovascular diseases, providing a perspective of the plausible lines of action that might eventually result in increasing our understanding of cardiovascular diseases. This analysis will come out with the building blocks for designing novel and innovative therapeutic approaches to healing the broken hearts.

Detection of Coronary Artery and Aortic Arch Anomalies in Patients with Tetralogy of Fallot Using CT Angiography

Background: Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease (CHD). Furthermore, the prevalence of anomalous origin of a coronary artery is higher in patients with TOF than in the general population (6% vs. ≤1%). Preoperative assessment of cardiovascular anatomy using computed tomography (CT) angiography enables the adaptation of the surgical approach to avoid potentially overlooked anomalies. Our purpose was to determine the prevalence of coronary artery and aortic arch anomalies in a cohort of TOF patients. Methods: In this retrospective analysis, data were collected from CT reports (2015–2021) of 105 TOF patients. All images were acquired using a 64-slice multi-detector CT (MDCT) scanner. Results: The median age of the patients was 38.7 months, with a male-to-female ratio of 1.39. The overall prevalence of coronary artery anomalies (CAAs) was 7.61% (8 of 105 cases). The anomalous origin and course of coronary arteries across the right ventricular outflow tract (RVOT; prepulmonic course) were defined in 5.71% of cases (six patients). In four of these, the left anterior descending artery (LAD) originated from the right coronary artery (RCA), while in two cases, the RCA arose from the LAD. In the remaining two patients, the coronary arteries followed an interarterial course. The most frequent anomalous aortic arch pattern in the overall TOF population was the right aortic arch (RAA) with mirror image branching, seen in 20% of patients (21 cases). The most frequent anomaly of the supra-aortic trunks was bovine configuration, found in 17.14% (18 cases). Conclusions: The prevalence of CAAs and aortic arch anomalies detected by CT angiography was in line with the data reported in anatomical specimens. Therefore, this technique represents a powerful tool for the evaluation of congenital cardiovascular anomalies.

Surgical Strategies for Preservation of Pulmonary Valve Function in a Radical Operation for Tetralogy of Fallot: A Systematic Review and Meta-Analysis

Objective

To evaluate the efficacy and safety of different surgical strategies to preserve pulmonary valve function. Surgical procedures evaluated include intraoperative balloon pulmonary valvuloplasty (IBPV), pulmonary valve reconstruction, and commissurotomy and pulmonary cusp augmentation (PCA) in patients who underwent a radical operation for Tetralogy of Fallot (ToF).

Materials and Methods

The five databases searched in the current study included the Cochrane Library, PubMed, China National Knowledge Infrastructure, VIP, and WanFang data. A systematic search for control trials was performed in each database from the start date of each database until December 2021. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of included studies.

Results

A total of 15 retrospective studies with a total number of 1,396 participants were included in this study. In subgroup 1 (IBPV vs. TAP), patients undergoing IBPV had a less degree of regurgitation at 1–2 years after the surgery. The reintervention rate increased in the IBPV group at 5 years. In subgroup 2 (pulmonary valve reconstruction vs. TAP), the degree of regurgitation decreased in the pulmonary valve reconstruction group at 1 month after the surgery. In subgroup 3 (valve-sparing operation vs. TAP), the comparison demonstrated decreased rates for surgical mortality and reintervention at 5–10 years after the surgery.

Conclusion

We proposed that pulmonary valve function in a radical operation for ToF was preserved. IBPV, pulmonary valve reconstruction, and commissurotomy and PCA can be performed during the surgical procedure based on the developmental status and anatomical characteristics of the right ventricular outflow tract (RVOT), pulmonary valve, and pulmonary artery.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022300987].

Conjunctival congestion: a novel clinical sign in older children with Tetralogy of Fallot

Tetralogy of Fallot is the most common cyanotic heart disease in children. While doing echocardiographic examination of children with Tetralogy of Fallot, we observed that many older children with this condition had congestion in their bulbar conjunctiva, easily recognizable even from some distance. This observation led us to design and perform a research study in order to find out the presence of conjunctival congestion in children with Tetralogy of Fallot. 85% of children in the ≥ 5-years of age group had conjunctival congestion without any ocular symptom. This novel clinical finding can act as an adjunct clinical sign for recognizing Tetralogy of Fallot in older children.

Cardiac Concerns in the Pediatric Athlete

Cardiovascular disease remains the number one cause of death in Americans. It is no secret that exercise mitigates this risk. Exercise and regular physical activity are beneficial for physical health including aerobic conditioning, endurance, strength, mental health, and overall improved quality of life. Unfortunately, today many children and adolescents are sedentary, lacking the recommended daily amount of physical activity, leading to higher rates of obesity, cardiovascular disease, stroke, diabetes, anxiety, and depression. Given this rising concern, the World Health Organization launched a 12-year plan to improve physical activity in children and adolescents by reducing the inactivity rate by 15% in the world. How does this apply to children and adolescents with acquired or congenital heart disease?.

Role of CT in the Pre- and Postoperative Assessment of Conotruncal Anomalies

Conotruncal anomalies, also referred to as outflow tract anomalies, are congenital heart defects that result from abnormal septation of the great vessels' outflow tracts. The major conotruncal anomalies include tetralogy of Fallot, double-outlet right ventricle, transposition of the great arteries, truncus arteriosus, and interrupted aortic arch. Other defects, which are often components of the major anomalies, include pulmonary atresia with ventricular septal defect, pulmonary valve agenesis, aortopulmonary window, and double-outlet left ventricle. CT has emerged as a robust diagnostic tool in preoperative and postoperative assessment of various congenital heart diseases, including conotruncal anomalies. The data provided with multidetector CT imaging are useful for treatment planning and follow-up monitoring after surgery or intervention. Unlike echocardiography and MRI, CT is not limited by a small acoustic window, metallic devices, and need for sedation or anesthesia. Major advances in CT equipment, including dual-source scanners, wide-detector scanners, high-efficiency detectors, higher x-ray tube power, automatic tube current modulation, and advanced three-dimensional postprocessing, provide a low-risk, high-quality alternative to diagnostic cardiac catheterization and MRI. This review explores the various conotruncal anomalies and elucidates the role of CT imaging in their pre- and postoperative assessment. Keywords: CT, CT Angiography, Stents, Pediatrics © RSNA, 2022.

Tissue engineering: Relevance to neonatal congenital heart disease

Congenital heart disease (CHD) represents a large clinical burden, representing the most common cause of birth defect-related death in the newborn. The mainstay of treatment for CHD remains palliative surgery using prosthetic vascular grafts and valves. These devices have limited effectiveness in pediatric patients due to thrombosis, infection, limited endothelialization, and a lack of growth potential. Tissue engineering has shown promise in providing new solutions for pediatric CHD patients through the development of tissue engineered vascular grafts, heart patches, and heart valves. In this review, we examine the current surgical treatments for congenital heart disease and the research being conducted to create tissue engineered products for these patients. While much research remains to be done before tissue engineering becomes a mainstay of clinical treatment for CHD patients, developments have been progressing rapidly towards translation of tissue engineering devices to the clinic.

Major Aortopulmonary Collateral Arteries

Major aortopulmonary collateral arteries (MAPCAs) are congenital vessels that arise from the aorta or its first-order branches and are distally connected to the pulmonary arterial vasculature, thereby providing pulmonary blood flow. MAPCAs are commonly associated with several congenital heart diseases that have compromised pulmonary circulation due to severe stenosis involving pulmonary valves or arteries or due to pulmonary atresia. Embryologically, MAPCAs are presumed to be persistent segmental arteries. MAPCAs can be imaged with CT and MRI, and such imaging findings are important for surgeons and interventionists. The management options for MAPCAs include unifocalization, surgical ligation, and endovascular interventions, such as coil embolization. This review highlights the role of reporting certain critical features of MAPCAs at CT and MRI, which will help to facilitate management decisions for systemic-to-pulmonary collateral vessels observed in patients with congenital heart disease. Keywords: Pediatrics, CT Angiography, Image Postprocessing, Interventional-Vascular, MR Angiography, Embolization, Stents, Cardiac, Vascular, Aorta © RSNA, 2022.

Circular Network of Coregulated Sphingolipids Dictates Chronic Hypoxia Damage in Patients With Tetralogy of Fallot

Background: Tetralogy of Fallot (TOF) is the most common cyanotic heart disease. However, the association of cardiac metabolic reprogramming changes and underlying molecular mechanisms in TOF-related chronic myocardial hypoxia damage are still unclear.

Methods: In this study, we combined microarray transcriptomics analysis with liquid chromatography tandem-mass spectrometry (LC–MS/MS) spectrum metabolomics analysis to establish the metabolic reprogramming that occurs in response to chronic hypoxia damage. Two Gene Expression Omnibus (GEO) datasets, GSE132176 and GSE141955, were downloaded to analyze the metabolic pathway in TOF. Then, a metabolomics analysis of the clinical samples (right atrial tissue and plasma) was performed. Additionally, an association analysis between differential metabolites and clinical phenotypes was performed. Next, four key genes related to sphingomyelin metabolism were screened and their expression was validated by real-time quantitative PCR (QT-PCR).

Results: The gene set enrichment analysis (GSEA) showed that sphingolipid metabolism was downregulated in TOF and the metabolomics analysis showed that multiple sphingolipids were dysregulated. Additionally, genes related to sphingomyelin metabolism were identified. We found that four core genes, UDP-Glucose Ceramide Glucosyltransferase (UGCG), Sphingosine-1-Phosphate Phosphatase 2 (SGPP2), Fatty Acid 2-Hydroxylase (FA2H), and Sphingosine-1-Phosphate Phosphatase 1 (SGPP1), were downregulated in TOF.

Conclusion: Sphingolipid metabolism was downregulated in TOF; however, the detailed mechanism needs further investigation.

Congenital Heart Disease in Adults with Autosomal Dominant Polycystic Kidney Disease

INTRODUCTION

Autosomal dominant polycystic kidney disease (ADPKD) is caused mainly by pathogenic variants in PKD1 or PKD2 encoding the polycystin-1 and -2 proteins. Polycystins have shown to have an essential role in cardiac development and function in animal models. In the current study, we describe the clinical association between ADPKD and congenital heart disease (CHD).

METHODS

Medical records from Mayo Clinic were queried for all patients with confirmed ADPKD and CHD between 1993 and 2020. CHD was categorized into left-to-right shunt, obstructive, and complex lesions. Patent foramen ovale, mitral valve prolapse, and bicuspid aortic valve anomalies were excluded.

RESULTS

Twenty-five out of 1,359 (1.84%) ADPKD patients were identified to have CHD. Of these, 84% were Caucasians and 44% were males. The median (Q1-Q3) age (years) at CHD diagnosis was 12.0 (2.0-43.5). Fourteen patients (56%) had left-to-right shunt lesions, 6 (24%) had obstructive lesions and 5 (20%) complex lesions. Seventeen patients (68%) had their defects surgically corrected at a median age (Q1-Q3) of 5.5 (2.0-24.7). Among 13 patients with available genetic testing, 12 (92.3%) had PKD1 pathogenic variants, and none had PKD2. The median (Q1-Q3) age at last follow-up visit was 47.0 (32.0-62.0) and median (Q1-Q3) eGFR was 35.8 (11.4-79.0) mL/min/1.73 m2. Three patients (12%) died; all of them had left-to-right shunt lesions.

DISCUSSION/CONCLUSION

We observed a higher CHD frequency in ADPKD than the general population (1.84 vs. 0.4%). While only PKD1 pathogenic variants were identified in this cohort, further studies are needed to confirm this novel finding and understand the role of polycystins in the development of the heart and vessels.

Right Ventricular Strain Is Associated With Increased Length of Stay After Tetralogy of Fallot Repair

BACKGROUND

Little is known regarding right ventricular (RV) remodeling immediately after Tetralogy of Fallot (TOF) repair. We sought to describe myocardial deformation by cardiac magnetic resonance imaging (CMR) after TOF repair and investigate associations between these parameters and early post-operative outcomes.

METHODS

Fifteen infants underwent CMR without sedation as part of a prospective pilot study after undergoing complete TOF repair, prior to hospital discharge. RV deformation (strain) was measured using tissue tracking, in addition to RV ejection fraction (EF), volumes, and pulmonary regurgitant fraction. Pearson correlation coefficients were used to determine associations between both strain and CMR measures/clinical outcomes.

RESULTS

Most patients were male (11/15, 73%), with median age at TOF repair 53 days (interquartile range, 13,131). Most patients had pulmonary stenosis (vs. atresia) (11/15, 73%) and 7 (47%) received a transannular patch as part of their repair. RV function was overall preserved with mean RV EF of 62% (standard deviation [SD], 9.8). Peak radial and longitudinal strain were overall diminished (mean ± SD, 33.80 ± 18.30% and −15.50 ± 6.40%, respectively). Longer hospital length of stay after TOF repair was associated with worse RV peak radial ventricular strain (correlation coefficient (r), −0.54; p = 0.04). Greater pulmonary regurgitant fraction was associated with shorter time to peak radial RV strain (r = −0.55, p = 0.03).

CONCLUSIONS

In this small study, our findings suggest presence of early decrease in RV strain after TOF repair and its association with hospital stay when changes in EF and RV size are not yet apparent.