Biventricular interaction and aortic function in adult patients with repaired tetralogy of Fallot: a two-dimensional-three-dimensional speckle-tracking echocardiographic study.

Aims: In patients late after correction of tetralogy of Fallot (TOF), the combined effects of pre-operative hypertrophy and hypoxia, ventricular interdependence, acquired post-operative lesions such as pulmonary or aortic regurgitation, and congenital vasculopathy may result in impaired right ventricular (RV) and left ventricular (LV) function. The aim of the present study was to investigate the interventricular interactions in repaired TOF (rTOF) and the impact of aortic function on biventricular performance using two-dimensional (2D-STE) and three-dimensional speckle-tracking echocardiography (3D-STE). Methods and results: Twenty-five adult patients with rTOF and 25 age- and gender-matched healthy controls were studied. LV and RV volumes were determined by 3D-STE and cardiac magnetic resonance. LV and RV longitudinal strains (LVLS and RVLS) and LV and RV area strains (LVAS and RVAS) and LV twist/rotation were calculated by 3D-STE. Ascending aorta circumferential strain (AAo-CS) was obtained using 2D-STE. LV 3D-STE parameters were decreased in rTOF patients compared with controls even in patients with normal ejection fraction. AAo-CS was decreased (6.7 ± 1.9 vs. 10.1 ± 2.6, P = 0.003) in rTOF patients compared with controls even in the presence of normal aortic dimensions and correlated with AAo diameter (r = -0.69, P = 0.0001), LV twist (r = 0.54, P = 0.004), LVAS (r = -0.56, P = 0.003), and RVLS (r = -0.39, P = 0.036). LVAS and AAo-CS were associated with disease severity (peak oxygen consumption and arrhythmia occurrence). Significant improvement in global χ 2 value was noted with RV 3D-STE parameters + LVAS + AAo-CS compared with RV dysfunction alone for detecting exercise capacity impairment (from 77.1 to 84.4 to 91.2, P = 0.003). Conclusion: Speckle-tracking echocardiography revealed subtle LV and AAo dysfunction in adults with rTOF. A correlation was observed between LV and RV strain changes and between AAo strain impairment and LV/RV dysfunction. LV and AAo changes had an incremental value in evaluating disease severity.

Transcatheter Pulmonary Valve Implantation in Repaired Tetralogy of Fallot and Anomalous Left Coronary Artery Origin.

We describe a rare and extremely challenging case of transcatheter pulmonary valve implantation in repaired tetralogy of Fallot and anomalous origin of the left main coronary artery from the right coronary sinus. Procedural planning based on advanced multimodality imaging and 3-dimensional technology proved to be the key to procedural success.

Pulmonary Artery Dilatation Due to Pressure or Volume Overload in Congenital Heart Disease.

Background: Pulmonary artery dilatation is described mostly in association with pulmonary hypertension. Patients/Methods: Study analysis: 60 patients with pulmonary arterial hypertension in congenital heart disease (PAH-CHD); 64 with repaired tetralogy of Fallot/pulmonary regurgitation (rTOF/PR); and 80 healthy (NORMAL). Measured were: main pulmonary artery (MPA) diameter and MPA/ascending aorta (Ao asc) ratio, by echocardiography (ECHO) and computer tomography or magnetic resonance imaging (CT/MRI). Results: In MPA diameter, significant differences between PAH-CHD, rTOF/PR, and NORMAL were found (median): 37 vs. 27 vs. 21 mm (p < 0.0001). In MPA/Ao asc ratio, there was a difference between PAH-CHD and NORMAL (median): 1.3 vs. 0.8 (p < 0.0001), but not between rTOF/PR and NORMAL: 0.74 vs. 0.8 (p = 0.3). Significant MPA dilatation (>40 mm) was present: in PAH-CHD, 35% (ECHO) and 76.9% (CT/MRI) of patients, while in rTOF/PR, 3.1% (ECHO) and 7.8% (CT/MRI). Severe MPA dilatation (>50 mm) occurred only in PAH-CHD: 16.7% (ECHO) and 31.4% (CT/MRI), while not in rTOF/PR. There was a significant correlation between ECHO and CT/MRI measurements, but ECHO was underestimated in all parameters. Conclusions: MPA dilatation due to pressure overload is more frequent and more severe; volume overload also leads to MPA dilatation but is less severe. The MPA/Ao asc ratio is not reliable for MPA dilatation estimation in rTOF/PR.

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.

Complex Substrate Leading to PVC-Mediated Systolic Dysfunction in addition to Sustained Monomorphic VT in Repaired Tetralogy of Fallot.

Frequent premature ventricular complexes (PVCs) are associated with deleterious effects on left ventricular (LV) function in various clinical scenarios. Repaired tetralogy of Fallot (rTOF) is frequently affected by sustained ventricular arrhythmias dependent on complex post-surgical substrates. However, there is limited data regarding the potential of arrhythmogenic isthmuses to generate frequent PVCs and PVC-mediated LV systolic dysfunction development in rTOF. We present a case of rTOF experiencing relatively infrequent episodes of internal shocks for episodes of sustained monomorphic ventricular tachycardia and a high burden of PVCs associated with left ventricular systolic function deterioration, in which the successful substrate ablation of the anatomical VT isthmuses also led to PVC abolition and consequently to LV systolic function normalization. In such cases, understanding the pathogenic mechanisms that lead to LV dysfunction is only possible by rigorous clinical reasoning, which leads to a tailored specific treatment.

Right-Left Ventricular Interdependence in Repaired Tetralogy of Fallot Patients With Right Ventricular Heart Failure.

BACKGROUND: Patients with repaired tetralogy of Fallot (rTOF) continue to face a heightened risk of deteriorating cardiac function, and quantitative techniques of cardiac MRI-derived cardiac structure and function provide an opportunity to explore the causes and mechanisms of cardiac deterioration. PURPOSE: To explore right-left ventricular interdependence in rTOF patients before and after the onset of right ventricular (RV) heart failure. STUDY TYPE: Retrospective. POPULATION: One hundred eighteen rTOF patients (21.85 [16.74, 29.20] years, 58 females) and 34 controls (23.5 [21, 26.5] years, 17 females) that underwent cardiac MRI were analyzed, with rTOF patients being further subdivided into those with preserved RV function (N = 54) and those that experienced RV heart failure (N = 64). FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession sequence. ASSESSMENT: RV, left ventricular (LV), and septal strain; RV and LV volume. STATISTICAL TESTS: Chi-squared tests or Fisher's exact test, One-way ANOVAs with Bonferroni's post hoc test, Pearson/Spearman correlation, and multivariate backward linear regression analysis. A two-tailed P < 0.05 was deemed as the significance threshold. RESULTS: The MRI-derived RV, LV, and septal strain decreased sequentially in controls, patients with preserved RV function, and patients with RV heart failure, with a good intra-observer (0.909-0.964) and inter-observer (0.879-0.937) agreement. Correlations between LV and RV strain were found to change sequentially with RV function and were the closest in rTOF patients with RV heart failure (r = -0.270 to 0.506). Correlations between RV volume and septal strain was variable in controls (r = 0.483 to -0.604), patients with preserved RV function (r = -0.034 to -0.295), and patients with RV heart failure (r = -0.026 to 0.500). Multivariate analyses revealed that the RV longitudinal strain was independently correlated with LV strain in three directions in rTOF patients with RV heart failure (Radial -0.70 [-1.33, -0.06]; Circumferential 0.44 [0.17, 0.72]; Longitudinal 0.54 [0.26, 0.81]). DATA CONCLUSION: In rTOF patients, the coupling between RV volume and septal strain was broken during RV function compensation, and the adverse effect of RV on LV deformation was highest in patients with RV heart failure. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 5.

Overcoming Underpowering in the Outcome Analysis of Repaired-Tetralogy of Fallot: A Multicenter Database from the CMR/CT Working Group of the Italian Pediatric Cardiology Society (SICPed).

Background: Managing repaired tetralogy of Fallot (TOF) patients is still challenging despite the fact that published studies identified prognostic clinical or imaging data with rather good negative predictive accuracy but weak positive predictive accuracy. Heterogeneity of the initial anatomy, the surgical approach, and the complexity of the mechanism leading to dilation and ventricular dysfunction explain the challenge of predicting the adverse event in this population. Therefore, risk stratification and management of this population remain poorly standardized. Design: The CMR/CT WG of the Italian Pediatric Cardiology Society set up a multicenter observational clinical database of repaired TOF evaluations. This registry will enroll patients retrospectively and prospectively assessed by CMR for clinical indication in many congenital heart diseases (CHD) Italian centers. Data collection in a dedicated platform will include surgical history, clinical data, imaging data, and adverse cardiac events at 6 years of follow-up. Summary: The multicenter repaired TOF clinical database will collect data on patients evaluated by CMR in many CHD centers in Italy. The registry has been set up to allow future research studies in this population to improve clinical/surgical management and risk stratification of this population.

Comprehensive echocardiographic assessment of right ventricular function, pulmonary arterial elastic properties and ventricular-vascular coupling in adult patients with repaired tetralogy of fallot: clinical significance of 3D derived indices.

We aimed to comprehensively analyze by three-dimensional speckle-tracking echocardiography (3DSTE) and Doppler echocardiography right ventricular (RV) performance, pulmonary arterial (PA) elastic properties and right ventricular-pulmonary artery coupling (RVPAC) in patients with repaired tetralogy of Fallot (rTOF) and assess the feasibility and clinical utility of related echocardiographic indices. Twenty-four adult patients with rTOF and twenty-four controls were studied. RV end-diastolic volume(3D-RVEDV), RV end-systolic volume(3D-RVESV), RV ejection fraction(3D-RVEF), RV longitudinal strain(3D-RVLS) and RV area strain(3D-RVAS) were calculated by 3DSTE. RV end-systolic area (RVESA) was obtained by planimetry. Pulmonary regurgitation (PR) was assessed as trivial/mild or significant by cardiac magnetic resonance (CMR) and color-Doppler. Pulmonary artery (PA) elastic properties were determined using two-dimensional/Doppler echocardiography. RV systolic pressure (RVSP) was measured using standard Doppler methods. RVPAC was assessed using various 3DSTE-derived parameters (3DRVAS/RVSP, 3DRVLS/RVESA, 3DRVAS/RVESV). Overall, 3DRVEF and 3DRVAS were impaired in rTOF patients compared with controls. PA pulsatility and capacitance were reduced (p = 0.003) and PA elastance was higher (p = 0.0007) compared to controls. PA elastance had a positive correlation with 3DRVEDV (r = 0.64, p = 0.002) and 3DRVAS (r = 0.51, p = 0.02). By ROC (receiver operating characteristics) analysis, 3DRVAS/RVESV, 3DRVAS/RVSP and 3DRVLS/RVESA cutoff values of 0.31%/mmHg, 0.57%/mmHg and 0.86%/mmHg, respectively, had 91%, 88% and 88% sensitivity and 81%, 81% and 79% specificity in identifying exercise capacity impairment. In rTOF patients increased 3DSTE-derived RV volumes and impaired RV ejection fraction and strain are associated with reduced PA pulsatility and capacitance and increased PA elastance. 3DSTE-derived RVPAC parameters using different afterload-markers are accurate indices of exercise capacity.

Semi-automated quantification of tricuspid valve dynamics and structure in tetralogy of Fallot and hypoplastic left heart syndrome using three-dimensional echocardiography.

Anomalies of the tricuspid valve (TV) are associated with worsened prognosis in congenital heart disease (CHD). Here, we present a descriptive study examining changes in TV morphology in two CHD conditions-repaired tetralogy of Fallot (rTOF) and hypoplastic left heart syndrome (HLSH), using three-dimensional echocardiography. Full volume acquisitions of the TV and right ventricle (RV) were performed from an RV-focused apical view using ECG gating over 2-5 consecutive cardiac cycles using 3D echocardiography, from which TV annulus and leaflet parameters were quantified. A total of 40 rTOF patients (age 14 ± 9.8 years), 40 HLHS patients (age1.0 ± 1.5 years) and 80 age and gender matched controls were included. Among leaflet parameters, antero-posterior and posterior-septal TV coaptation heights were smaller in rTOF (p < 0.001) vs. control. Conversely, only the short-axis TV height was different in HLHS vs. controls (HLHS 1.6 ± 0.4 cm vs. control 1.4 ± 0.3 cm). TV leaflet parameters tended to be larger in HLHS, while leaflet coaptation distances were similar between groups. We demonstrate that 3D echocardiography for assessment of the TV is feasible in rTOF and HLHS patients and identifies unique differences in TV morphology. Future studies should clarify the clinical significance of TV morphology in these patient populations.

Reversal of Right Ventricular Remodeling After Correction of Pulmonary Regurgitation in Tetralogy of Fallot.

In the sheep model with pathophysiologic changes similar to patients with repaired TOF, severe PR leads to fibrotic changes in the RV. Pulmonary valve replacement reverses these fibrotic changes. Early valve replacement led to a quick RV recovery, and in time there was no difference in outcome between early and late valve replacement. These data support the benefit of valve replacement for RV function and suggest that there is a margin in the timing of the surgery. The fibrotic changes correlated well with the circulating biomarker PICP, which can have an added value in the clinical follow-up of patients with repaired TOF.

The value of myocardial strain imaging in the evaluation of patients with repaired Tetralogy of Fallot: a review of the literature.

Tetralogy of Fallot (ToF) is considered to be the most common, complex, cyanotic congenital heart disease (CHD) representing 7-10% of all congenital heart defects, whereas the patients with ToF are the most frequently operated in their early infancy or childhood. Cardiac magnetic resonance (CMR) consists a valuable imaging technique for the diagnosis and serial follow-up of CHD patients. Furthermore, in recent years, advanced echocardiography imaging techniques have come to the fore, aiming to achieve a complete and more accurate evaluation of cardiac function using speckle tracking imaging modalities. We conducted a review of the literature in order to assess the myocardial deformation of patients with repaired ToF (rToF) using echocardiographic and CMR parameters. Patients with rToF have impaired myocardial strain parameters, that are well standardized either with the use of speckle tracking echocardiography or with the use of CMR imaging. Subclinical left ventricular dysfunction (low GLS) and myocardial dyssynchrony are commonly identified in rToF patients. Impaired left atrium (LA) and right atrium (RA) mechanics are, also, a common finding in this study population, but the studies using atrial strain are a lot fewer than those with LV and RV strain. No studies using myocardial work were identified in the literature, as far as rToF patients are concerned, which makes it an ideal field for further investigation.

Incremental prognostic value of myocardial strain over ventricular volume in patients with repaired tetralogy of Fallot.

OBJECTIVES: The relative incremental predictive value of myocardial deformation over ventricular volume for future adverse events in patients with repaired tetralogy of Fallot (rTOF) remains unknown. We aimed to determine the incremental prognostic value of myocardial deformation over ventricular volume to predict adverse events in patients with rToF. METHODS: We retrospectively included patients with rTOF who completed cardiac magnetic resonance (CMR) and follow-up in our hospital from January 2014 to October 2020, and stratified according to the presence or absence of adverse events during follow-up. The strain parameters of the right ventricular (RV) and left ventricular (LV) were obtained from CMR-derived feature tracking. Multivariable Cox proportional hazard models and net reclassification improvement analysis were used to analyze the prognostic information of biventricular strain and volume parameters in rTOF patients. RESULTS: Among 98 patients with rTOF, 54 (55.1%) experienced primary and/or secondary events during a median follow-up period of 27.0 months. Univariable analysis indicated that RV volume and strain were significantly associated with both primary events and all adverse events (all p < .01). Multivariable Cox regression and net reclassification improvement analyses achieved incremental global χ2 (all p < .001), C index (all p < .001), and overall correct reclassification by sequentially adding CMR-derived RV volume, RV strain and LV strain parameters to preexisting clinical factors in adverse events model analyses. CONCLUSIONS: RV and LV myocardial deformation provided incremental prognostic information and significant improvement for risk stratification over RV size and clinical variables and therefore can be combined to further enhance prognostication. KEY POINTS: • RV volume and strain were significantly associated with both primary events and all adverse events, whereas LV volume and strain were associated with primary events. • Ventricular myocardial deformation is a strong predictor of adverse outcomes of patients with repaired tetralogy of Fallot, providing increased prognostic information and significantly improved risk stratification over ventricular size.

Left ventricular strain derived from cardiac magnetic resonance can predict outcomes of pulmonary valve replacement in patients with repaired tetralogy of Fallot.

Purpose: Several adults with repaired tetralogy of Fallot (rToF) undergo pulmonary valve replacement (PVR) to reduce the right ventricular volume and retain right ventricular function. However, there is currently no consensus on the ideal time for PVR surgery in asymptomatic patients with rTOF with pulmonary regurgitation (PR). Clinical outcomes after PVR are also indeterminate. Recently, myocardial strain and strain rate derived from cardiac magnetic resonance (CMR) feature tracking were found to be more sensitive to right ventricular dysfunction than conventional parameters and therefore may add prognostic value in patients with rToF. We aimed to analyze whether pre-PVR left ventricular (LV) strain and strain rate detected by CMR feature tracking are associated with midterm outcomes after PVR in patients with rToF. Methods: Seventy-eight asymptomatic patients with rToF who required PVR due to moderate or severe PR were prospectively enrolled between January 2014 and June 2020. CMR cine sequences were obtained, and feature tracking parameters were measured preoperatively. Adverse events were documented during the follow-up. Receiver operating characteristic analysis was performed to determine the cutoff value. Kaplan-Meier curves were drawn with log-rank statistics; moreover, univariate and multivariate Cox proportional hazards regression analyses and Harrel C-indices were analyzed. Results: During 3.6 ± 1.8 years of follow-up, 25 adverse events were recorded. Kaplan-Meier survival curves and univariate Cox analysis verified that patients with significantly reduced radial strain (RS), circumferential strain (CS), longitudinal strain (LS), RS rate at systole and diastole (RSRs and RSRe), and circumferential and LS rates at diastole (CSRe and LSRe) had worse event-free survival. After multivariate correction, only LS and LSRe remained significantly associated with adverse outcomes (hazard ratio = 1.243 [1.083-1.428] and 0.067 [0.017-0.258], respectively, all p < 0.05). The cutoff values of LS and LSRe were -12.30 (%) and 1.07 (s-1), respectively. Conclusion: The LV strain and strain rate prior to PVR are important prognostic factors for adverse events after PVR in rToF.

Pulmonary Valve Replacement in Repaired Tetralogy of Fallot: Midterm Impact on Biventricular Response and Adverse Clinical Outcomes.

Background: Pulmonary regurgitation (PR), though well tolerated for short term in patients with repaired tetralogy of Fallot (rTOF), could lead to right ventricular (RV) dysfunction, arrhythmias, and sudden cardiac death. Pulmonary valve replacement (PVR), considered as the gold-standard treatment for PR, is performed to mitigate these late effects. In this study, we aimed to evaluate the midterm outcomes and predictors of adverse clinical outcomes (ACO). Methods: From May 2014 to December 2017, 42 patients with rTOF undergoing surgical or transcatheter PVR in our department were retrospectively included. Cardiovascular magnetic resonance was performed before PVR (pre-PVR), early after PVR (early post-PVR), and midterm after PVR (midterm post-PVR). Medical history and individual data were collected from medical records. ACO included all-cause death, new-onset arrhythmia, prosthetic valve failure, and repeat PVR. Results: The median follow-up duration was 4.7 years. PVR was performed at a median age of 21.6 years. There was no early or late death. Freedom from ACO at 3 and 5 years was 88.1 ± 5% and 58.2 ± 9%, respectively. RV end-diastolic volume index (RVEDVI) and end-systolic volume index (RVESVI) significantly reduced early after PVR and further decreased by midterm follow-up (pre-PVR vs. early post-PVR vs. midterm post-PVR: RVEDVI, 155.2 ± 34.7 vs. 103.8 ± 31.2 vs. 95.1 ± 28.6 ml/m2, p < 0.001; RVESVI, 102.9 ± 28.5 vs. 65.4 ± 28.2 vs. 57.7 ± 23.4 ml/m2, p < 0.001). Multivariable analysis revealed that the occurrence of ACO was significantly increased in patients with lower left ventricular end-systolic volume index. Conclusions: A significant reduction of RV volume occurred early after PVR, followed by a further improvement of biventricular function by midterm follow-up. The midterm freedom from ACO was favorable.

Hand-sewn expanded polytetrafluoroethylene valved conduit for right ventricular outflow tract reconstruction. / 手工缝制的膨体聚四氟乙烯带瓣管道在右室流出道重建中的应用.

OBJECTIVES: Due to the lack of large-sized pulmonary valved conduit products in clinical practice, hand-sewn expanded polytetrafluoroethylene (ePTFE) valved conduit has been used for right ventricular outflow tract (RVOT) reconstruction in many heart centers around the world. This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress, and to provide a reference for the application of ePTFE valved conduit. METHODS: A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital, Central South University from October 2018 to October 2020 were prospectively enrolled in this study. The age at the implantation of the conduit was 4.3 to 43.8 (median 15.1) years old, with weight of (38.9±4.1) kg. In this cohort, 14 patients underwent re-reconstruction of RVOT, including 12 patients with pulmonary regurgitation at 6.3 to 31.0 (median 13.8) years after tetralogy of Fallot (TOF) repair, and 2 patients with failed bovine jugular vein conduit (BJVC). Seven patients underwent Ross operations. Among them, 3 were for aortic valve stenosis, 2 were for aortic regurgitation, and 2 were for both stenosis and regurgitation. The ePTFE valved conduits were standard hand-sewn during the surgery. The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus. The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter. The height of the valve sinus was 4/5 of the diameter. The junction of the valve leaflet was 3/4 of the height of the sinus. The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit. Valved conduits with diameter of 18, 20, and 22 mm were used in 2, 9, and 10 cases, respectively. The surgical results, postoperative recovery time, and serious complications were summarized, and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated. RESULTS: During the implantation of ePTFE valved conduit for RVOT reconstruction, 2 patients underwent mechanical mitral valve replacement with Ross operation, 2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty, and 1 patient with failed BJVC underwent tricuspid valvuloplasty. The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was (130.9±16.9) min, with aorta clamping for 1 patient to repair the residual defect of the ventricular septum. The cardiopulmonary bypassing and aorta clamping time for Ross operation were (242.7±20.6) min and (145.6±10.5) min, respectively. The duration of postoperative ventilator assistance, intensive care unit stay, and hospital stay were 3.5 h to 7.7 d (median 17.1 h),11.2 h to 29.5 d (median 1.9 d), and 6.0 to 56.0 (median 13.0) d, respectively. All patients survived after discharge from hospital. The follow-up rate after discharge was 100% with median time at 15.0 (13.0 to 39.0) months. No death happened during the follow-up. One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation. One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT. The cardiac function of all patients recovered to NYHA class I 6 months after operation. The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was (9.4±2.6) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (P=0.134). No patient suffered from mild or more pulmonary regurgitation. CONCLUSIONS: Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction. It is a promising material for RVOT reconstruction which can effectively meet clinical need. In our experience, the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit, attention should be paid to implantation indications and postoperative anticoagulation management, especially to the preparation details of the valved conduit, to obtain better function and durability of the conduit after implantation.

Ventricular flow analysis and its association with exertional capacity in repaired tetralogy of Fallot: 4D flow cardiovascular magnetic resonance study.

BACKGROUND: Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) allows quantification of biventricular blood flow by flow components and kinetic energy (KE) analyses. However, it remains unclear whether 4D flow parameters can predict cardiopulmonary exercise testing (CPET) as a clinical outcome in repaired tetralogy of Fallot (rTOF). Current study aimed to (1) compare 4D flow CMR parameters in rTOF with age- and gender-matched healthy controls, (2) investigate associations of 4D flow parameters with functional and volumetric right ventricular (RV) remodelling markers, and CPET outcome. METHODS: Sixty-three rTOF patients (14 paediatric, 49 adult; 30 ± 15 years; 29 M) and 63 age- and gender-matched healthy controls (14 paediatric, 49 adult; 31 ± 15 years) were prospectively recruited at four centers. All underwent cine and 4D flow CMR, and all adults performed standardized CPET same day or within one week of CMR. RV remodelling index was calculated as the ratio of RV to left ventricular (LV) end-diastolic volumes. Four flow components were analyzed: direct flow, retained inflow, delayed ejection flow and residual volume. Additionally, three phasic KE parameters normalized to end-diastolic volume (KEiEDV), were analyzed for both LV and RV: peak systolic, average systolic and peak E-wave. RESULTS: In comparisons of rTOF vs. healthy controls, median LV retained inflow (18% vs. 16%, P = 0.005) and median peak E-wave KEiEDV (34.9 µJ/ml vs. 29.2 µJ/ml, P = 0.006) were higher in rTOF; median RV direct flow was lower in rTOF (25% vs. 35%, P < 0.001); median RV delayed ejection flow (21% vs. 17%, P < 0.001) and residual volume (39% vs. 31%, P < 0.001) were both greater in rTOF. RV KEiEDV parameters were all higher in rTOF than healthy controls (all P < 0.001). On multivariate analysis, RV direct flow was an independent predictor of RV function and CPET outcome. RV direct flow and RV peak E-wave KEiEDV were independent predictors of RV remodelling index. CONCLUSIONS: In this multi-scanner multicenter 4D flow CMR study, reduced RV direct flow was independently associated with RV dysfunction, remodelling and, to a lesser extent, exercise intolerance in rTOF patients. This supports its utility as an imaging parameter for monitoring disease progression and therapeutic response in rTOF. Clinical Trial Registration https://www.clinicaltrials.gov . Unique identifier: NCT03217240.

Right and left ventricular function and flow quantification in pediatric patients with repaired tetralogy of Fallot using four-dimensional flow magnetic resonance imaging.

BACKGROUND: To assess the accuracy and reproducibility of right ventricular (RV) and left ventricular (LV) function and flow measurements in children with repaired tetralogy of Fallot (rTOF) using four-dimensional (4D) flow, compared with conventional two-dimensional (2D) magnetic resonance imaging (MRI) sequences. METHODS: Thirty pediatric patients with rTOF were retrospectively enrolled to undergo 2D balanced steady-state free precession cine (2D b-SSFP cine), 2D phase contrast (PC), and 4D flow cardiac MRI. LV and RV volumes and flow in the ascending aorta (AAO) and main pulmonary artery (MPA) were quantified. Pearson's or Spearman's correlation tests, paired t-tests, the Wilcoxon signed-rank test, Bland-Altman analysis, and intraclass correlation coefficients (ICC) were performed. RESULTS: The 4D flow scan time was shorter compared with 2D sequences (P < 0.001). The biventricular volumes between 4D flow and 2D b-SSFP cine had no significant differences (P > 0.05), and showed strong correlations (r > 0.90, P < 0.001) and good consistency. The flow measurements of the AAO and MPA between 4D flow and 2D PC showed moderate to good correlations (r > 0.60, P < 0.001). There was good internal consistency in cardiac output. There was good intraobserver and interobserver biventricular function agreement (ICC > 0.85). CONCLUSIONS: RV and LV function and flow quantification in pediatric patients with rTOF using 4D flow MRI can be measured accurately and reproducibly compared to those with conventional 2D sequences.

Risk Factors of Right Ventricular Dysfunction and Adverse Cardiac Events in Patients with Repaired Tetralogy of Fallot.

AIM: This study evaluates the risk factors associated with right ventricular (RV) dilation and dysfunction leading to pulmonary valve replacement (PVR) or adverse cardiac events in repaired Tetralogy of Fallot (rToF) patients. METHODS: Data from all rToF patients who underwent magnetic resonance imaging (MRI) evaluation at our hospital between February 2007 and September 2020 were collected. RESULTS: Three hundred and forty-two patients (60% males, 42% older than 18 years), with a median age of 16 years (IQR 13-24) at the time of MRI, were included. All patients underwent complete repair at a median age of 8 months (IQR 5-16), while palliation was performed in 56 patients (16%). One hundred and forty-four patients (42%) subsequently received pulmonary valve replacement (PVR). At the multivariate analysis, male gender was an independent predictor for significant RV dilation, RV and left ventricular (LV) dysfunction. Transventricular ventricular septal defect (VSD) closure and previous palliation significantly affected LV function and RV size, respectively. Male gender and the transventricular VSD closure were independent predictors for PVR. CONCLUSIONS: Male gender and surgical history (palliation, VSD closure approach) significantly affected the long-term outcomes in rToF patients and should be taken into consideration in the follow-up management and in PVR timing in this patient population.

Branch Pulmonary Artery Regurgitation in Repaired Tetralogy of Fallot: Correlation with Pulmonary Artery Morphology, Distensibility, and Right Ventricular Function.

BACKGROUND: The aim was to determine the effect of pulmonary artery (PA) morphology on the branch pulmonary artery-regurgitation fraction (BPA-RF), the relationship of pulmonary insufficiency (PI) to BPA-RF and PA-distensibility, and factors (BPA-RF and PA-distensibility) associated with right ventricular function (RVF) in repaired tetralogy of Fallot (rTOF). METHODS: A total of 182 rTOF patients (median age 17.1 years) were analyzed for length, angle of PA, BPA-RF, PI, and PA-distensibility, using magnetic resonance imaging. RESULTS: The left PA had a significant greater RF than the right PA (median (interquartile range)): LPA 43.1% (32.6-51.5) and RPA 35.2% (24.7-44.7), p < 0.001. The LPA was shorter with a narrower angle than the RPA (p < 0.001). The anatomy of the branch-PA was not a factor for the greater LPA-RF (odds ratio, 95% confidence interval: CI, p-value): length 0.44 (0.95-2.00), p = 0.28; angle 0.63 (0.13-2.99), p = 0.56. There was a strong positive correlation between PI and BPA-RF-coefficients (95% CI), p-value: LPA 0.78% (0.70-0.86), p < 0.001; RPA 0.78% (0.71-0.84), p < 0.001 and between BPA-RF and distensibility-coefficients (95%CI), p-value: LPA 0.73% (0.37-1.09), p < 0.001; RPA 1.63% (1.22-2.03), p < 0.001, respectively. The adjusted BPA-RF did not predict RVF, RPA (p = 0.434), LPA (p = 0.268). CONCLUSIONS: PA morphology is not a significant factor for the differential BPA-RF. The vascular wall in rTOF patients responds to chronic increased intravascular volume by increasing distensibility. BPA-RF is not a determinant of RVF.

Follow-up aortic dilatation in patients with repaired tetralogy of Fallot using cardiovascular magnetic resonance.

PURPOSE: The study sought to determine the rate of aortic expansion and correlation with somatic growth in patients with repaired tetralogy of Fallot (rTOF), and predictors for determining the annual growth rate of the aorta (Ao-AGR). METHODS: Ninety-four rTOF patients (mean age 14.5 ± 4.4 years) with two cardiac magnetic resonance tests (CMR) (median duration 52 months, interquartile range, IQR 24-71) were analyzed for aortic diameter (AoD) at the annulus, the sinus of Valsalva (SoV), the sinotubular junction, and the ascending aorta (AAo), and compared with the normal limit AoD (NL-AoD) values. The median age-at-repair was 60 months (IQR 36-84). Ao-AGR and its index (Ao-AGRI) were derived from changes of the AoD and AoD-index, respectively, divided by the duration between the two studies. Three potential predictors (baseline AoD, sex, and age-at-repair) for the progression of Ao-AGR were analyzed. RESULTS: There was a significant larger AoD than NL-AoD (p < 0.001). Slow aortic growth was encountered in 78-85 % of patients. The Ao-AGR was slow, the median AGR ranged from 0.37 mm (IQR 0.13-0.72) at annulus to 0.56 mm (IQR 0.22-0.91) at AAo. There was a regression in Ao-AGRI, ranged from -1.41 mm (IQR -1.94, -0.87) at annulus to -2.36 mm (IQR -3.09, -1.63) at SoV. The three predictors were not correlated with severity of Ao-AGR. CONCLUSION: Most adolescents with rTOF show significant aortic dilatation. There is a slow Ao-AGR with regression of Ao-AGRI, which may suggest that the rate of aortic growth is slower than the somatic growth. There are no significant predictors of the progression of Ao-AGR.