Prospective Cohort Research of Aortic Root Dilatation after Surgical Repair in Adults with Tetralogy of Fallot(TRANSIT)

Background:Aortic root dilatation occurs in adults with tetralogy of Fallot(TOF)after surgical repair,but the longitudinal changes are unclear.The main research aim is to determine the annual dilatation rate of aorta in adults with repaired TOF.Methods:The present,multicentric,prospective cohort study assessed the rate of aortic diameter change in adults aged 20 years or older with TOF,including pulmonary artery atresia,who underwent surgical repair.Clinical data,focusing on echocardiograms,were collected at three-year intervals from seven hos-pitals.Results:In total,104 patients(58 males;median age:29 years)were enrolled.The actual Valsalva sinus(VS)diameter was 34.3±5.8(mean±standard deviation)and 36.1±6.0 mm at the initial andfinal examinations,respectively,and the annual dilatation rate was 0.64(0.07,1.33)(median,interquartile)mm/year.The corrected diameter at the respective examination was 21.3±3.8 and 22.2±3.7 mm/m^(2),and the annual dilation rate was 0.28(-0.21,0.76)mm/m^(2)/year.Multiple regression analysis showed that factors significant associated with dila-tation rate of actual VS diameter were the diastolic blood pressure(standardized coefficient-0.22;p=0.04),cardiothoracic ratio(0.28;0.02),and the ratio of early mitral valve inflow velocity to early diastolic annular velocity(E/e′)ratio(0.31;0.004).Factors significantly associated with corrected VS diameter were diastolic blood pressure(-0.25;0.02)and the E/e′ratio(0.34;0.001).Conclusions:In adults with repaired TOF,the rate of dilatation of the aortic diameter was associated with decreased diastolic blood pressure and left ventricular diastolic dysfunction,possibly reflecting decreased aortic wall elasticity.

Severe hypoxemia after radiofrequency ablation for atrial fibrillation in palliatively repaired tetralogy of Fallot: A case report

BACKGROUND Patients with tetralogy of Fallot(TOF)often have arrhythmias,commonly being atrial fibrillation(AF).Radiofrequency ablation is an effective treatment for AF and does not usually cause severe postoperative hypoxemia,but the risk of complications may increase in patients with conditions such as TOF.CASE SUMMARY We report a young male patient with a history of TOF repair who developed severe hypoxemia after radiofrequency ablation for AF and was ultimately confirmed to have a new right-to-left shunt.The patient subsequently underwent atrial septal occlusion and eventually recovered.CONCLUSION Radiofrequency ablation may cause iatrogenic atrial septal injury;thus possible complications should be predicted in order to ensure successful treatment and patient safety.

Right ventricular diverticulum following a pulmonary valve placement for correction of tetralogy of Fallot:A case report

BACKGROUND Ventricular diverticula are a rare congenital cardiac disorder presenting with an extremely low incidence.The presence of an apical diverticulum of the right ventricle has been associated with other congenital heart diseases such as tetralogy of Fallot.An important defining characteristic of ventricular diverticula that separates them from aneurysms through imaging techniques,is that they possess myocardial contraction synchronous to the adjacent walls,contributing to the ventricular stroke volume,so they do not usually require surgical treatment.CASE SUMMARY A 15-year-old male,currently asymptomatic,in follow up due to a pulmonary valve prosthesis placement and a history of corrected tetralogy of Fallot at 18 months old,underwent a cardiac magnetic resonance imaging in February 2024.A diverticulum was detected in the apical inferolateral wall of the right ventricle,which was not documented in the cardiac magnetic resonance imaging prior to valve prosthesis placement.CONCLUSION Right ventricular diverticula are a rare entity.To this date we could not find another case of a pulmonary valve placement,followed by a right ventricular diverticulum appearance.

Evaluation of Right Ventricular Global Longitudinal Function in Patients with Tetralogy of Fallot by Two-dimensional Ultrasound Speckle Tracking Imaging

Quantification of right ventricular(RV)volume and function remains a challenge because of RV complex geometry by conventional echocardiography.The purpose of this study was to assess RV global longitudinal function in patients with tetralogy of Fallot(TOF)by 2-dimensional ultrasound speckle tracking imaging(STI).Thirty-eight patients with TOF were enrolled in this study and divided into child group(n=25)and adult group(n=13)according to age.Thirty-eight age-and sex-matched normal subjects were selected as c...

Anomalous origin of left pulmonary artery branch from the aorta with Fallot's tetralogy:one case report

We report the case of a ten-year-old boy who had often presented with respiratory distress since born. Chest X-ray showed an enlarged right ventricle. Echocardiography demonstrated characteristic features of Fallot＇s tetralogy and the left pulmonary artery could not be visualized. However, cardiac catheterization disclosed that the left pulmonary artery had an anomalous origin in the ascending aorta. The patient underwent total surgical correction of the defects. Nine days later, he was discharged. We present the results of a literature review of the incidence, physiopathological, clinical, diagnostic, and surgical characteristics of this rare disease.

Anisotropic Models of Human Pulmonary Root with Bicuspid Pulmonary Valve in Patients with Tetralogy of Fallot: Pulmonary Root Function Assessment and Mechanical Stress Analysis

Background Tetralogy of Fallot(TOF)is the most common cyanotic heart defect,accounting for 10%of all congenital defects.Pulmonary valve stenosis(PVS)is one common right ventricular outflow tract obstruction problem in patients with TOF.Congenital bicuspid pulmonary valve(BPV)is a condition of valvular stenosis,which morphologic feature is the presence of only two pulmonary leaflets instead of the normal tri-leaflet.Congenitally BPV are uncommon and the occurrence is often associated with TOF.Methods The three-dimensional geometric reconstruction of pulmonary root(PR)were based on well-accepted mathematical analytic models with physiological parameters obtained from a typical sample of the pulmonary root used in clinical surgery.The PR geometry included valvular leaflets,sinuses,interleaflet triangles and annulus.The dynamic computational models of normal PR with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions and the geometric orifice area.Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing of human pulmonary valve left leaflet,and characterized by an anisotropic Mooney-Rivlin model.The complete cardiac cycle was simulated to observe valve leaflet dynamic stress and strain behaviors.Results Our results indicated that stress/strain distribution patterns of normal tri-leaflet pulmonary valve(TPV)and the BPV were different on valve leaflets when the valve was fully open,but they were similar when valves were completely closed.When the valve was fully open,the BPV maximum stress value on the leaflets was 218.1 kPa,which was 128.0%higher than of the normal TPV value(95.6 kPa),and BPV maximum strain value on the leaflets was 70.7%higher than of the normal TPV.The location of the maximum stress from TPV and BPV were also different,which were found at the bottom of the valve near the leaflet attachment for TPV and the vicinity of cusp of the fusion of two leaflets for BPV,respectively.During the valve was fully open,the stress distribution in the interleaflet triangles region of the PR was more asymmetric in the BPV model compared with that in the normal TPV model,and the largest change on the PR with the geometrical variations in the two models was 39.6%in maximum stress.This stress asymmetry indicates that BPV may be one of the causes of post-stenotic pulmonary artery dilatation and aneurysm in patients with TOF.The cusp of the BPV model showed significant eccentricity during peak systolic period,and its geometric orifice area value in the completely opened position of valve was reduced 57.5%from that of the normal TPV model.Conclusions Our initial results demonstrated that valve geometrical variations with BPV may be a potential risk factor linked to occurrence of PVS in patients with TOF.Computational models could be used as an effective tool to identifying possible linkage between pulmonary valve malformation disease development and biomechanical factors,better design of artificial valves and new surgical procedures without testing those on patients.Large-scale clinical studies are needed to validate these preliminary findings.

Improving Right Ventricle Cardiac Function for Repaired Tetralogy of Fallot Patient with Contracting Bands: A Modelling Study

Objective Patients with repaired tetralogy of Fallot(rTOF)account for the majority of cases with late onset right ventricle(RV)failure.The current surgical approach,including pulmonary valve replacement/insertion(PVR),has yielded mixed results with some patients recover RV function and some do not.An innovative surgical approach was proposed to help ventricle to contract and improve RV function qualified by ejection fraction with one or more active contracting bands.Computational biomechanical modelling is a widely used method in cardiovascular study for investigation of mechanisms governing disease development,quantitative diagnostic and treatment strategies and improving surgical designs for better outcome.Muscle active contraction caused by zero-load sarcomere shortening leads to change of zero-load configurations.In lieu of experimenting using real surgery on animal or human,computational simulations(virtual surgery)were performed to test different band combination and insertion options to identify optimal surgery design and band insertion plan.Methods Cardiac magnetic resonance(CMR)data were obtained from one rTOF patient(sex:male,age:22.5 y)before pulmonary valve replacement surgery.The patient was suffering from RV dilation and dysfunction with RV end-systole volume 254.49ml and end-diastole volume 406.91 mL.A total of 15 computational RV/LV/Patch/Band combination models based on(CMR)imaging were constructed to investigate the influence of different band insertion surgery plans.These models included 5 different band insertion models combined and 3 different band contraction ratio(10%,15%and 20%band zero-stress length reduction).These models included 5 different band insertion models:Model 1 with one band at anterior to the middle of papillary muscle;Model 2 with one band at posterior to the middle of papillary muscle;Model 3 with 2 bands which are the ones from Models 1&2 combined;Model 4 with a band at the base of the papillary muscle;Model 5 with 3 bands which is a combination of Models 3&4.A pre-shrink process was performed on in-vivo begin-filling and end-systole MRI data to obtain diastole and systole zero4oad ventricle geometries.An extra 5%-8%shrinkage was applied to obtain corresponding systole zero-load geometry reflecting myocardium sarcomere shortening.The zero-load band length in systole was 10%,15%and 20%shorter than that in diastole according to their corresponding contraction ratio.The nonlinear Mooney-Rivlin model was used to describe the ventricle material properties with their material parameter values adjusted to match measured data with CMR.The band material properties were in the same scale with healthy right ventricle.The RV/LV/Band model construction and solution procedures were the same as described.Results Model 5 with band contraction ratio of 20%has the ability to improve RV ejection fraction to 41.07%,which represented a 3.61%absolute improvement,or 9.6%relative improvement using pre-PVR ejection fraction as the baseline number.The ejection fractions for Models 1-4 with band contraction ratio of 20%were 39.28%,39.47%,38.87%and 40.34%respectively.Compared to models with band contraction ratio15%and 20%,models with band contraction ratio 10%has the least ability on RV ejection fraction improvement with ejection fraction 38.28%,38.00%,38.81%,38.50%and 39.36%corresponding to Models 1-5.Conclusions This pilot work demonstrated that the band insertion surgery may have great potential to improve post-PVR RV cardiac function for patients with repaired TOF.More band contraction ratio and inserted band number may lead to better post-surgery outcome.Further investigations using in-vitro animal experiments and final patient studies are warranted.

Scalp block for brain abscess drainage in a patient with uncorrected tetralogy of Fallot

We report a case of an 11-year-old boy with diagnosed but uncorrected tetralogy of Fallot presented to us for brain abscess drainage. The child was managed successfully with scalp block with sedation.

A novel concept and surgical breakthrough in primary repair of Tetralogy of Fallot:a mid-term result from a prospective,single center trial

Objective This trial aims to evaluate the safety and feasibility of consecutive and nonselective non-transannular patch enlargement(TAPE)in Tetralogy of Fallot(TOF)populations with a series of annulus-sparing strategies in primary repairs.Methods We conducted a prospective,single center trial.All included patients divide into groups according to pulmonary valvular annulus(PVA)z-score and whether TAPE.

Predictive value of preoperative cardiopulmonary exercise testing on early outcomes of pulmonary valve replacement after repair of Tetralogy of Fallot

Objective Cardiopulmonary exercise testing(CPET)is helpful to identify right ventriclar(RV)dysfunction in patients with rapair of Tetralogy of Fallot(rTOF),but its predictive value on early outcomes of pulmonary valve replacement(PVR)of these patients is unclear when similar preoperative ventricular size and function in cardiovascular magnetic resonance(CMR)exist.The aim of this study is to evaluate whether CPET is useful to predict the early outcomes of rTOF patients after PVR.

Polytetrafluoroethylene Patch versus Autologous Pericardial Patch for Right Ventricular Outflow Tract Reconstruction in Patients with Tetralogy of Fallot

Objective: For patients of TOF with pulmonary annular hypoplasia, reconstruction of right ventricular outflow tract (RVOT) often requires a trans annular patch (TAP). The present study aims to compare the outcomes of TOF repair using Polytetrafluoroethylene (PTFE) patch versus autologous glutaraldehyde fixed pericardial patch for RVOT reconstruction. Materials and methods: 103 consecutive patients undergoing TOF repair in whom TAP was required were randomized into two groups: Group I (pericardial patch), Group II (PTFE patch). Postoperative outcomes in terms of postoperative heart rhythm, duration of mechanical ventilation, mediastinal and pleural drainage, length of stay in intensive care unit (ICU) and hospital mortality were assessed. A separate team of cardiologists independently evaluated pre- and post-operative gradients across the RVOT, degree of pulmonary insufficiency, right ventricular systolic function. Results: There were no significant differences between the two groups in terms of the incidence of postoperative arrhythmias, duration of mechanical ventilation, length of intensive care unit or hospital stay. The requirement of inotropes was no different in the PTFE patch group as compared with the pericardial patch group (16.84 ± 7.04 vs. 17.90 ± 6.71, median 19 vs. 20, p = 0.825). The re-exploration rate was higher in the PTFE group as compared with the pericardial patch group (6 vs. 1). Postoperative Echocar-diography revealed no differences in the RV systolic function between the two groups before discharge. Conclusion: In patients undergoing TOF repair, using a PTFE patch yields comparable results. However, the efficacy of PTFE will only be established once;mid-term and long-term results are available.

Assessment of Right Ventricular Function in Post Operative Patients of Tetralogy of Fallots and Its Predictive Factors

Introduction: Right ventricular (RV) dysfunction can occur early and late in patients after intracardiac repair (ICR) for Tetralogy of Fallots (TOF). This study focuses on early RV dysfunction as there is limited data on it. Aims & Objective: RV function was studied with respect to its incidence, course over 3 months, co-relation with peri operative factors and serum iron levels. Material & Method: All patients of TOF undergoing ICR during July 2007-October 2008, done by single surgeon at a single centre, were prospectively studied. Patients were divided into group A (with RV dysfunction) and group B (without RV dysfunction). All patients underwent pre operative & post operative clinical assessment, biochemical evaluation (serum iron profile & CK MB) and 2D echocardiography (pulse Doppler & tissue Doppler). Echocardiography was done at 24 hours, 4 weeks & 12 weeks of ICR. Patients were also assessed for intra operative parameters including cross clamp time, by pass time, acidosis, RV and PA pressures. Results: 24 patients underwent ICR (transannular patch repair) with mean age of 7.31 ± 4.74 years. RV dysfunction was present in 13 patients (54.2%) but was persistent only in 15.3% (2/13) at 12 weeks. Presence of cyanotic spell (p = 0.006), recurrent chest infection (p = 0.002), raised heamatocrit (p = 0.02), and rise in serum iron level (p = 0.002) were significantly associated with post operative RV dysfunction. It resulted in prolong ICU stay and slower recovery. Pre operative RV dysfunction was associated with difficult weaning from bypass and poor post operative outcome (p < 0.001). Conclusion: RV dysfunction is commonly present even after satisfactory ICR. Its aetiology remains unclear in such setting. In our study, pre operative clinical profile and serum iron fluctuations were important determinants of post operative outcome.

Primary Results of Late Surgical Treatment in Children with Tetralogy of Fallot from a Developing Country

Objectives: The purpose was to show how important is to operate on the Senegalese African children presenting with Tetralogy of Fallot (TOF) regardless of their age. Methods: It is a retrospective, descriptive analysis of data from the Department of Pediatric Cardiology, University Hospital of Tuebingen’s data base which was searched for all cases of TOF in foreign patients younger than 15 years between 05/2004-10/2016. Results: 16 children from Senegal with TOF were referred for treatment. Mean age of patients was 7.0 years (range 0.9 - 14.8 years). Primary corrective surgery was performed in 13/16 patients. A primary shunt procedure was required in 3/16 patients. All patients were discharged in good condition with a median 13 postoperative days. We did not register any deaths. All became asymptomatic with pulse oximetry oxygen saturations greater than 95%. The right ventricular outflow tract (RVOT) gradient was less than 30 mmHg in all patients and 2 patients had moderate pulmonary valvular insufficiency. Conclusions: It was still necessary to operate Senegalese children presenting with TOF irrespective of their age.

The Variation in Plasma Cortisol Levels in Response to Anesthetic Induction with Etomidate or Ketamine in Children Undergoing Intracardiac Repair of Tetralogy of Fallot on Cardiopulmonary Bypass

Objective: To compare the effect of a single induction dose of etomidate or ketamine on plasma cortisol levels in children with Tetralogy of Fallot (TOF) undergoing intra-cardiac repair on cardiopulmonary bypass (CPB). Design: A prospective randomized trial. Setting: Cardiac center of a tertiary care hospital. Participants: Thirty children with TOF undergoing intra-cardiac repair on CPB. Interventions: After random allocation of the children into two groups, the children either received etomidate 0.2 mg/kg or ketamine 2 mg/kg intravenously for anesthetic induction along with fentanyl 2 mcg/kg and midazolam 100 mcg/kg. Endotracheal intubation was accomplished with rocuronium bromide in the dose of 1 mg/kg. Anesthesia was maintained with sevoflurane in air-oxygen, titrated to response and supplemental vecuronium bromide for muscle relaxation, fentanyl chloride for pain relief. Serum cortisol was measured on three occasions, at preinduction, at the end of surgery and at 24 hours postoperatively. Measurements and Main Results: Baseline plasma cortisol (Normal 5 - 25 mcg/dl) in the etomidate group (19.91 ± 3.51 mcg/dl) decreased significantly at the end of surgery (5.78 ± 2.0 mcg/dl) and rose to significantly higher than baseline values at 24 hours (27.31 ± 8.30 mcg/dl). The baseline cortisol levels in the ketamine group (20.91 ± 3.19 mcg/dl) increased significantly at the end of surgery (44.02 ± 5.49 mcg/dl) and remained significantly higher than baseline at 24hours (45.93 ± 3.05 mcg/dl). Plasma cortisol levels in the etomidate group at end of surgery, and at 24 hours post-operatively, were significantly lower than the ketamine group. Conclusions: This study shows that etomidate is a suitable and safe agent for suppression of the increase in serum cortisol associated with the use of CPB in children with TOF undergoing intra-cardiac repair.

Isolation of Left Subclavian Artery with Tetralogy of Fallot—A Case Report

Background: Isolation of Left Subclavian Artery (LSCA) is a rare subset of Right Aortic Arch (RAA). It is diagnosed as nonvisualization of LSCA in catheterization study. Case Presentation: Here we report an unusual case of Tetralogy of Fallot (TOF) with right aortic arch with isolation of left subclavian artery (LSCA). Here LSCA originated from left pulmonary artery (LPA) through an atretic patent ductus arteriosus (PDA). There was nonvisualization of LSCA in catheterization study and it was confirmed by Computed Tomography (CT) angiography. Re-implantation of LSCA was done to left common carotid artery (LCCA) so that the left upper arm maintains a better flow in the future. Conclusion: Isolation of LSCA especially with TOF is a very rare entity. Re-implantation of LSCA to LCCA was done in view of weak pulses in left upper limb. Results were satisfactory in the follow up period.

Predictors for Dilated Aorta in Repaired and Unrepaired Tetralogy of Fallot

Aortic root pathology has been described in patients with Tetralogy of Fallot, although the most common reason for repeat surgery in the adult after TOF repair relates to problems in the right ventricular outflow tract, the aortic root is often forgotten. Objective: We sought to determine those patients with known Fallot tetrallogy at risk for progressive dilatation of the thoracic aorta and explore the common predictors present in this patient group. Methods and Results: A multicenter observational study which enrolled 100 patients (50 surgically repaired and 50 before surgical repair of TOF) with standardized reassessment of echocardiographic parameters and multislice CT angiography of the heart and great vessels data. The data were reviewed and analyzed according to the demographic, morphological, surgical and clinical details. We used standard nomograms and Z score for aortic root dimensions at the level of aortic annulus, sino-tubular junction and sinus of Valsalva based on body surface area. For surgically repaired patients, all the measured diameters across aortic annulus, STJ & sinus of Valsalva were larger in the dilated unrepaired group with mean & median of 24.63 (3.99) & 25 (15 - 35), 27.2 (4.26) & 27 (17 - 40), 35.97 (4.59) & 36 (24 - 45) mm respectively compared to a mean & median of 13.2 (2.62) & 13 (9 - 17), 14.53 (2.90) & 14 (10 - 19), 20.53 (3.40) & 21 (14 - 25) mm respectively in the not dilated unrepaired group with significant statistical difference (p value < 0.0001). Also Z score among unrepaired dilated TOF patients was larger in comparison to the non dilated unrepaired group with significant statistical difference (p value < 0.0001). For unrepaired patients, all the measured diameters across aortic annulus, STJ & sinus of Valsalva were larger in the dilated unrepaired group with mean & median of 24.63 (3.99) & 25 (15 - 35), 27.2 (4.26) & 27 (17 - 40), 35.97 (4.59) & 36 (24 - 45) mm respectively compared to a mean & median of 13.2 (2.62) & 13 (9 - 17), 14.53 (2.90) & 14 (10 - 19), 20.53 (3.40) & 21 (14 - 25) mm respectively in the not dilated unrepaired group with significant statistical difference (p value < 0.0001). Also Z score among unrepaired dilated TOF patients at the level of annulus, STJ & sinus of Valsalva was larger in comparison to the non dilated unrepaired group with significant statistical difference (p value < 0.0001). Conclusions: The first important finding of this study is the occurrence of significant aortic root dilatation in 22% of patients after intra-cardiac repair of TOF. Older age at repair, long shunt to repair interval and residual ventricular septal defect are the most common variables associated with aortopathy and aortic regurgitation in such group of patients. The second important finding is the occurrence of aortic root dilatation in 70% of patients before surgical repair of TOF;whereas male sex and TOF with pulmonary atresia appeared to be the most common variables associated with aortopathy and aortic regurgitation in this group of patients.

Fresh Pericardial Valved Conduit for Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot with Pulmonary Stenosis or Pulmonary Atresia—Early Results

Objective: To study early results of hand made fresh (autologous/homologous) pericardial valved conduit in achieving right ventricle to pulmonary artery continuity. Method: Between November 2014 and September 2015, 19 cases, with diagnosis of Tetralogy of Fallot with Pulmonary stenosis (PS) or Pulmonary atresia (PA) underwent intracardiac repair and Right Ventricular Outflow Tract (RVOT) reconstruction with hand made fresh [autologous (n = 2)/ homologous (n = 17)] pericardial valved conduit. Mean age of the patients at time of surgery was 6.37 years (range 3 months to 18 years), mean weight was 18.52 kilograms (range 6 kg to 40 kg) and mean size of the conduit was 20.7 mm (range 16 mm to 24 mm). Results: All patients had a smooth post-operative course, with mean ICU (Intensive Care Unit) stay of 3.6 days (range 3 days to 6 days) and mean post-operative hospital stay 8.5 days (range 7 days to 16 days). Intra-operative and Post-operative echocardiography revealed moderate Pulmonary regurgitation (PR) in one patient, mild PR in 5 patients and no or trace PR in 13 patients. No patient has developed conduit stenosis or calcification till now. Conclusion: Autologous or homologous pericardial valved conduit provides good early results and is especially suitable for developing world because of zero cost. Long term usefulness of such option remains to be confirmed in terms of dilation, calcification and freedom from intervention.

Pulmonary Perfusion Asymmetry in Patients after Repair of Tetralogy of Fallot: A 4D Flow MRI-Based Study

Background:Repaired Tetralogy of Fallot(rTOF)patients may have residual lesions such as main(MPA)and branch pulmonary artery stenosis(BPAS).While MPA stenosis is well studied,few data are available on BPAS in rTOF.We aimed to describe pulmonary perfusion in a large paediatric cohort of rTOF and its impact on right ventricular and outflow-tract hemodynamics using 4D flow CMR.Methods:130 consecutive patients(mean age at CMR 14.3±4.6 years)were retrospectively reviewed.96 patients had transannular patch without valve preservation while 34 patients had conserved annulus or valved conduit.A pulmonary blood flow ratio(right pulmonary artery(RPA)/left pulmonary artery(LPA))between 0.75 and 1.56 was considered normal.Results:Asymmetric pulmonary perfusion was present in 59/130 patients(45%),with 54/59(91%)having left lung hypoperfusion(blood flow ratio>1.56).RPA/LPA perfusion ratio in the whole cohort was independently associated with the LPA Z-score(−0.053,p=0.007),the RPA regurgitant fraction(RF)(0.013,p=0.011)and previous LPA stenting(0.648,p=0.004).Decreasing LPA%perfusion(and conversely increasing RPA%perfusion)was significantly associated with higher MPA diameter Z-score(−0.06,p=0.007).On multivariate analysis,MPA Z-score was independently associated with pulmonary RF(0.48,p<0.001)and with right ventricular indexed volumes(coefficient 3.6,p=0.023).In patients with transannular patch repair,asymmetric pulmonary flow was an independent predictor of right ventricular ejection fraction(RVEF)(−3.66,p=0.04).Conclusions:Pulmonary perfusion asymmetry is frequent in rTOF and is associated with abnormal right ventricular and outflow-tract hemodynamics,including MPA dilatation and decreased RVEF in patients after transannular patch.

Single-Cell RNA Sequencing Reveals Potential for Endothelial-to-Mesenchymal Transition in Tetralogy of Fallot

Background:Tetralogy of Fallot(TOF)is a very common cyanotic congenital heart disease.Endothelial-to-mesenchymal transition(EndoMT)is recognized as a physiological mechanism involved in embryonic heart development and endothelial formation.However,there is still a gap in the reports related to the mechanism of EndoMT development in TOF.Methods:First,transcriptomic data of single cell nuclei of TOF and Donor were obtained based on the Gene Expression Omnibus(GEO)database,and the data were normalized and clus-tered by dimensionality reduction using the Seurat package.Subsequently,differentially expressed genes(DEGs)between TOF and Donor were screened using the“FindMarkers”function,and the gene sets of interest were enriched.Finally,to characterize the dynamics of EndoMT occurrence in TOF,we performed pseudotime cell tra-jectory inference as well as utilized SCENIC analysis to probe the gene regulatory networks(GRNs)dominated by transcription factors(TFs)in endothelial cells.Results:We identified a total of six cell clusters based on single-cell nuclear transcriptome data from TOF and Donor.We found that 611 genes with up-regulated expression within TOF showed conversion to mesenchyme.By subdividing endothelial cell subtypes,endothelial cells 2 were shown to be involved in cell adhesion,migration and extracellular matrix processes.Pseudo-time and SCENIC analyses showed that endothelial cell 2 has EndoMT potential.In addition,ERG and TEAD1 are TFs that play key reg-ulatory roles in this subtype,and both of their target genes are also highly expressed in TOF.This demonstrates that ERG and TEAD1 effectively promote the EndoMT process.Conclusion:Our study reveals the molecular mechanisms underlying the development of EndoMT in TOF,which demonstrates that manipulating the endothelial-to-mesenchymal transition may offer unprecedented therapeutic potential for the treatment of TOF.

Surgical Treatment of Tetralogy of Fallot with Pulmonary Valve Agenesis in a 22 Years Old Patient

Agenesis of pulmonary valve is a rare variant and severe form of Tetralogy of Fallot (ToF). The evolution is usually marked by respiratory and cardiac failure at early age, which needs early surgical correction. Uncorrected treatment of Tetralogy of Fallot diagnosed at adult age is infrequent and only few studies have been described. We present here a rare case of a 22 years old patient who presented with dyspnea since childhood. Subsequent investigations allowed diagnosis of treatment of Tetralogy of Fallot with agenesis of the pulmonary valve. Following the assessment, the patient underwent a surgical repair and the recovery was uneventful. The management of treatment of Tetralogy of Fallot with pulmonary valve agenesis in adult period remains complex, requiring different surgical techniques.