Three-dimensional cardiac magnetic resonance allows the identification of slow-conducting anatomical isthmuses in tetralogy of Fallot.

BACKGROUND AND AIMS: Patients with repaired tetralogy of Fallot remain at risk of life-threatening ventricular tachycardia related to slow-conducting anatomical isthmuses (SCAIs). Preventive ablation of SCAI identified by invasive electroanatomical mapping is increasingly performed. This study aimed to non-invasively identify SCAI using 3D late gadolinium enhancement cardiac magnetic resonance (3D-LGE-CMR). METHODS: Consecutive tetralogy of Fallot patients who underwent right ventricular electroanatomical mapping (RV-EAM) and 3D-LGE-CMR were included. High signal intensity threshold for abnormal myocardium was determined based on direct comparison of bipolar voltages and signal intensity by co-registration of RV-EAM with 3D-LGE-CMR. The diagnostic performance of 3D-LGE-CMR to non-invasively identify SCAI was determined, validated in a second cohort, and compared with the discriminative ability of proposed risk scores. RESULTS: The derivation cohort consisted of 48 (34 ± 16 years) and the validation cohort of 53 patients (36 ± 18 years). In the derivation cohort, 78 of 107 anatomical isthmuses (AIs) identified by EAM were normal-conducting AI, 22 were SCAI, and 7 blocked AI. High signal intensity threshold was 42% of the maximal signal intensity. The sensitivity and specificity of 3D-LGE-CMR for identifying SCAI or blocked AI were 100% and 90%, respectively. In the validation cohort, 85 of 124 AIs were normal-conducting AI, 36 were SCAI, and 3 blocked AI. The sensitivity and specificity of 3D-LGE-CMR were 95% and 91%, respectively. All risk scores showed an at best modest performance to identify SCAI (area under the curve ≤ .68). CONCLUSIONS: 3D late gadolinium enhancement cardiac magnetic resonance can identify SCAI with excellent accuracy and may refine non-invasive risk stratification and patient selection for invasive EAM in tetralogy of Fallot.

Balloon atrial septostomy for transposition of the great arteries: Safety and experience with the Z-5 balloon catheter.

BACKGROUND: Balloon atrial septostomy (BAS) is an emergent and essential cardiac intervention to enhance intercirculatory mixing at atrial level in deoxygenated patients diagnosed with transposition of the great arteries (TGA) and restrictive foramen ovale. The recent recall of several BAS catheters and the changes in the European legal framework for medical devices (MDR 2017/745), has led to an overall scarcity of BAS catheters and raised questions about the use, safety, and experience of the remaining NuMED Z-5 BAS catheter. AIMS: To evaluate and describe the practice and safety of the Z-5 BAS catheter, and to compare it to the performance of other BAS catheters. METHODS: A retrospective single-center cohort encompassing all BAS procedures performed with the Z-5 BAS catheter in TGA patients between 1999 and 2022. RESULTS: A total of 182 BAS procedures were performed in 179 TGA-newborns at Day 1 (IQR 0-5) days after birth, with median weight of 3.4 (IQR 1.2-5.7) kg. The need for BAS was urgent in 90% of patients. The percentage of BAS procedures performed at bedside increased over time from 9.8% (before 2010) to 67% (2017-2022). Major complication rate was 2.2%, consisting of cerebral infarction (1.6%) and hypovolemic shock (0.5%). The rate of minor complications was 9.3%, including temporary periprocedural AV-block (3.8%), femoral vein thrombosis (2.7%), transient intracardiac thrombus (0.5%), and atrial flutter (2.2%). BAS procedures performed at bedside and in the cardiac catheterization laboratory had similar complication rates. CONCLUSIONS: BAS using the Z-5 BAS catheter is both feasible and safe at bedside and at the cardiac catheterization laboratory with minimal major complications.

Somatic growth in single ventricle patients: A systematic review and meta-analysis.

AIM: To map somatic growth patterns throughout Fontan palliation and summarise evidence on its key modifiers. METHODS: Databases were searched for relevant articles published from January 2000 to December 2021. Height and weight z scores at each time point (birth, Glenn procedure, Fontan procedure and >5 years after Fontan completion) were pooled using a random effects meta-analysis. A random effects meta-regression model was fitted to model the trend in z scores over time. RESULTS: Nineteen studies fulfilled eligibility criteria, yielding a total of 2006 participants. The z scores for height and weight were markedly reduced from birth to the interstage period, but recovered by about 50% following the Glenn procedure. At >10 years after the Fontan procedure, the z scores for weight seemed to normalise despite persistent lower height, resulting in increased body mass index. The review revealed a number of modifiers of somatic growth, including aggressive nutritional management, timing of Glenn/Fontan, prompt resolution of complications and obesity prevention programmes in adolescence and adulthood. CONCLUSION: This review mapped the somatic growth of single ventricle patients and summarised key modifiers that may be amendable to improvement. These data provide guidance on strategies to further optimise somatic growth in this population and may serve as a benchmark for clinical follow-up.

4D flow cardiovascular magnetic resonance derived energetics in the Fontan circulation correlate with exercise capacity and CMR-derived liver fibrosis/congestion.

AIM: This study explores the relationship between in vivo 4D flow cardiovascular magnetic resonance (CMR) derived blood flow energetics in the total cavopulmonary connection (TCPC), exercise capacity and CMR-derived liver fibrosis/congestion. BACKGROUND: The Fontan circulation, in which both caval veins are directly connected with the pulmonary arteries (i.e. the TCPC) is the palliative approach for single ventricle patients. Blood flow efficiency in the TCPC has been associated with exercise capacity and liver fibrosis using computational fluid dynamic modelling. 4D flow CMR allows for assessment of in vivo blood flow energetics, including kinetic energy (KE) and viscous energy loss rate (EL). METHODS: Fontan patients were prospectively evaluated between 2018 and 2021 using a comprehensive cardiovascular and liver CMR protocol, including 4D flow imaging of the TCPC. Peak oxygen consumption (VO2) was determined using cardiopulmonary exercise testing (CPET). Iron-corrected whole liver T1 (cT1) mapping was performed as a marker of liver fibrosis/congestion. KE and EL in the TCPC were computed from 4D flow CMR and normalized for inflow. Furthermore, blood flow energetics were compared between standardized segments of the TCPC. RESULTS: Sixty-two Fontan patients were included (53% male, 17.3 ± 5.1 years). Maximal effort CPET was obtained in 50 patients (peak VO2 27.1 ± 6.2 ml/kg/min, 56 ± 12% of predicted). Both KE and EL in the entire TCPC (n = 28) were significantly correlated with cT1 (r = 0.50, p = 0.006 and r = 0.39, p = 0.04, respectively), peak VO2 (r = - 0.61, p = 0.003 and r = - 0.54, p = 0.009, respectively) and % predicted peak VO2 (r = - 0.44, p = 0.04 and r = - 0.46, p = 0.03, respectively). Segmental analysis indicated that the most adverse flow energetics were found in the Fontan tunnel and left pulmonary artery. CONCLUSIONS: Adverse 4D flow CMR derived KE and EL in the TCPC correlate with decreased exercise capacity and increased levels of liver fibrosis/congestion. 4D flow CMR is promising as a non-invasive screening tool for identification of patients with adverse TCPC flow efficiency.

Acute kidney injury after the arterial switch operation: incidence, risk factors, and outcomes.

BACKGROUND: The aim of this retrospective cohort study was to determine the incidence, potential risk factors, characteristics, and outcomes of acute kidney injury in children following the arterial switch operation for transposition of the great arteries. METHODS: Retrospective review of children who underwent ASO between 2000 and 2020 in our tertiary children's hospital in the Netherlands. Pre-and post-ASO serum creatinine levels were collected. Severe AKI was defined as 100% serum creatinine rise or estimated creatinine clearance <35 ml/min/1.73 m2 according to pRIFLE criteria. Logistic regression was used to adjust for confounders. RESULTS: A total of 242 children were included. Fifty-seven (24%) children developed severe AKI after ASO. Four patients with severe AKI were treated with renal replacement therapy. Children with severe AKI had a longer duration of mechanical ventilation 4.5 (1.0-29) versus 3 (1.0-12) days (p = 0.001), longer PICU stay 7 (2-76) versus 5 (1-70) days, (p = 0.001), higher rate of myocardial infarction 5% versus 0.5% (p = 0.001), sepsis 24% versus 9% (p = 0.002), post-operative pulmonary hypertension 19% versus 6% (p = 0.002), post-operative bleeding 9% versus 3% (p = 0.044), longer time to sternal closure 3 (1-19) versus 2 (1-6) days, (p = 0.009), and a higher mortality rate 9.0% versus 0.5% (p = 0.001) compared to children without severe AKI. Sepsis was a risk factor for developing severe AKI. CONCLUSIONS: In this single-centre cohort, 24% of our patients developed severe AKI after ASO, which is associated with increased morbidity, longer PICU stay, and higher mortality.

The prognosis of common arterial trunk from a fetal perspective: A prenatal cohort study and systematic literature review.

OBJECTIVE: The limited number of large fetal cohort studies on common arterial trunk (CAT) impedes prenatal counseling at midgestation. This study evaluates the prognosis of CAT from a fetal perspective. METHOD: Fetuses with a prenatally diagnosed CAT were extracted from the PRECOR registry (2002-2016). We evaluated fetal and postnatal survival and the presence of additional morbidity at last follow-up. Literature databases were searches systematically for additional cases. RESULTS: Thirty-eight cases with a prenatal diagnosis of CAT were identified in our registry, of which 18/38 (47%) opted for pregnancy termination (TOP). Two cases resulted in spontaneous intrauterine demise (10%, 2/20), six cases demised postnatally (33%, 6/18), leaving 60% (12/20) alive, after exclusion of TOP, at a mean age of six (range: 2-10 years). Additional morbidity was found in 42% (5/12) of survivors, including 22q11.2 deletion syndrome, Adams-Oliver syndrome and intestinal atresia, whereas 8% (1/12) had developmental delay. The remaining 30% (6/12) of survivors appeared isolated with normal development. All of whom six required replacement of the initial right ventricle to pulmonary artery conduit. Additionally, we reviewed 197 literature cases on short-term outcome. CONCLUSION: The risk of fetal and neonatal demise, as well as significant morbidity amongst survivors, should be included in prenatal counseling for CAT.

Rhinovirus Detection in the Nasopharynx of Children Undergoing Cardiac Surgery Is Not Associated With Longer PICU Length of Stay: Results of the Impact of Rhinovirus Infection After Cardiac Surgery in Kids (RISK) Study.

OBJECTIVES: To determine whether children with asymptomatic carriage of rhinovirus in the nasopharynx before elective cardiac surgery have an increased risk of prolonged PICU length of stay. STUDY DESIGN: Prospective, single-center, blinded observational cohort study. SETTING: PICU in a tertiary hospital in The Netherlands. PATIENTS: Children under 12 years old undergoing elective cardiac surgery were enrolled in the study after informed consent of the parents/guardians. INTERVENTIONS: The parents/guardians filled out a questionnaire regarding respiratory symptoms. On the day of the operation, a nasopharyngeal swab was obtained. Clinical data were collected during PICU admission, and PICU/hospital length of stay were reported. If a patient was still intubated 3 days after operation, an additional nasopharyngeal swab was collected. Nasopharyngeal swabs were tested for rhinovirus and other respiratory viruses with polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: Of the 163 included children, 74 (45%) tested rhinovirus positive. Rhinovirus-positive patients did not have a prolonged PICU length of stay (median 2 d each; p = 0.257). Rhinovirus-positive patients had a significantly shorter median hospital length of stay compared with rhinovirus-negative patients (8 vs 9 d, respectively; p = 0.006). Overall, 97 of the patients (60%) tested positive for one or more respiratory virus. Virus-positive patients had significantly shorter PICU and hospital length of stay, ventilatory support, and nonmechanical ventilation. Virus-negative patients had respiratory symptoms suspected for a respiratory infection more often. In 31% of the children, the parents reported mild upper respiratory complaints a day prior to the cardiac surgery, this was associated with postextubation stridor, but no other clinical outcome measures. CONCLUSIONS: Preoperative rhinovirus polymerase chain reaction positivity is not associated with prolonged PICU length of stay. Our findings do not support the use of routine polymerase chain reaction testing for respiratory viruses in asymptomatic children admitted for elective cardiac surgery.

Pulmonary ductal coarctation: An entity associated with congenital heart defects involving the right ventricle outflow tract.

We present a case of a prematurely born 2-month-old girl with a double outlet right ventricle with pulmonary atresia and a left pulmonary artery coarctation arising after ductal closure. The case highlights the importance of knowledge and identification of such an anomaly in patients with congenital heart malformations with severe pulmonary stenosis to atresia.

Oxygen Uptake Efficiency Slope is Strongly Correlated to VO2peak Long-Term After Arterial Switch Operation.

After the arterial switch operation (ASO) for transposition of the great arteries (TGA), many patients have an impaired exercise tolerance. Exercise tolerance is determined with cardiopulmonary exercise testing by peak oxygen uptake (VO2peak). Unlike VO2peak, the oxygen uptake efficiency slope (OUES) does not require a maximal effort for interpretation. The value of OUES has not been assessed in a large group of patients after ASO. The purpose of this study was to determine OUES and VO2peak, evaluate its interrelationship and assess whether exercise tolerance is related to ventricular function after ASO. A cardiopulmonary exercise testing, assessment of physical activity score and transthoracic echocardiography (fractional shortening and left/right ventricular global longitudinal peak strain) were performed to 48 patients after ASO. Median age at follow-up after ASO was 16.0 (IQR 13.0-18.0) years. Shortening fraction was normal (36 ± 6%). Left and right global longitudinal peak strain were reduced: 15.1 ± 2.4% and 19.5 ± 4.5%. This group of patients showed lower values for all cardiopulmonary exercise testing parameters compared to the reference values: mean VO2peak% 75% (95% CI 72-77) and mean OUES% 82(95% CI 77-87); without significant differences between subtypes of TGA. A strong-to-excellent correlation between the VO2peak and OUES was found (absolute values: R = 0.90, p < 0.001; normalized values: R = 0.79, p < 0.001). No correlation was found between cardiopulmonary exercise testing results and left ventricle function parameters. In conclusion, OUES and VO2peak were lower in patients after ASO compared to reference values but are strongly correlated, making OUES a valuable tool to use in this patient group when maximal effort is not achievable.

Altered Ascending Aorta Hemodynamics in Patients After Arterial Switch Operation for Transposition of the Great Arteries.

BACKGROUND: Patients with transposition of the great arteries (TGA) have an altered aortic geometry after an arterial switch operation (ASO), with neo-aortic root dilatation as an important complication. Geometry-related aortic hemodynamics have been assumed to contribute to pathology of the ascending aorta (AAo). PURPOSE: To evaluate aortic flow displacement (FD) and regional wall shear stress (WSS) in relation to ascending neo-aortic geometry in children after ASO. STUDY TYPE: Prospective. POPULATION: Twenty-eight TGA patients after ASO and 10 healthy volunteers. FIELD STRENGTH/SEQUENCE: 3.0T/4D flow (segmented fast-spoiled echo pulse), noncontrast-enhanced MR angiography (Dixon), and anatomic images (SSFP). ASSESSMENT: Aortic diameters and body surface area-indexed aortic dimensions (Z-scores), normalized FD and planar ascending aortic WSS. STATISTICAL TESTS: Mann-Whitney and chi-square tests for differences in FD magnitude, WSS, and FD directionality between groups, respectively. Spearman rank correlation to assess the degree of association between aortic geometry, FD and WSS parameters. Shapiro-Wilk test to evaluate distribution normality on the absolute differences in octant location between FD and WSS. RESULTS: TGA patients showed a significantly dilated proximal AAo and relatively small mid-AAo dimensions at the level of the pulmonary arteries (Z-scores neo-aortic root: 4.38 ± 1.96 vs. 1.52 ± 0.70, P < 0.001; sinotubular junction: 3.48 ± 2.67 vs. 1.38 ± 1.30, P = 0.010; mid-AAo: 0.32 ± 3.06 vs. 1.69 ± 1.24, P = 0.001). FD magnitude was higher in TGA patients (neo-aortic root: 0.048 ± 0.027 vs. 0.021 ± 0.006, P < 0.001; sinotubular junction: 0.054 ± 0.037 vs. 0.029 ± 0.013, P < 0.05) and was related to the neo-aortic Z-score. Clear areas of higher WSS at the right and anterior aortic wall regions along the distal AAo were detected in TGA patients, most pronounced in those with relatively smaller mid-AAo diameters. DATA CONCLUSION: TGA-specific geometry related to the ASO, evidenced by neo-aortic root dilatation and a sudden change in vessel diameter at mid-AAo level, leads to more aortic flow asymmetry in the proximal AAo and WSS distribution with higher WSS at the right and anterior aortic wall regions along the distal AAo. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:1105-1116.

Left and Right Ventricular Impairment Shortly After Correction of Tetralogy of Fallot.

Surgical repair of Tetralogy of Fallot (ToF) is usually performed in the first months of life with low early postoperative mortality. During long-term follow-up, however, both right (RV) and left ventricular (LV) performances may deteriorate. Tissue Doppler imaging (TDI) and speckle tracking echocardiography (ST) can unmask a diminished RV and LV performance. The objective of the current study was to assess the cardiac performance before and shortly after corrective surgery in ToF patients using conventional, TDI and ST echocardiographic techniques. Thirty-six ToF patients after surgery were included. Transthoracic echocardiography including TDI and ST techniques was performed preoperatively and at hospital discharge after surgery (10 days to 4 weeks after surgery). Median age at surgery was 7.5 months [5.5-10.9]. Regarding the LV systolic function there was a significant decrease in interventricular septum (IVS) S' at discharge as compared to preoperatively (pre IVS S' = 5.4 ± 1.4; post IVS S' = 3.9 ± 1.2; p < 0.001) and in global longitudinal peak strain (GLS) (pre = - 18.3 ± 3.4; post = - 14.2 ± 4.1; p = 0.003); but not in the fractional shortening (FS). Both conventional and TDI parameters showed a decrease in diastolic function at discharge. Tricuspid Annular Plane Systolic Excursion and RV S' were significantly lower before discharge. When assessing the RV diastolic performance, only the TDI demonstrated a RV impairment. There was a negative correlation between age at surgery and postoperative LV GLS (R = - 0.41, p = 0.031). There seems to be an impairment in left and right ventricle performance at discharge after ToF corrective surgery compared to preoperatively. This is better determined with TDI and ST strain imaging than with conventional echocardiography.

Energetics of Blood Flow in Cardiovascular Disease: Concept and Clinical Implications of Adverse Energetics in Patients With a Fontan Circulation.

Visualization and quantification of the adverse effects of distorted blood flow are important emerging fields in cardiology. Abnormal blood flow patterns can be seen in various cardiovascular diseases and are associated with increased energy loss. These adverse energetics can be measured and quantified using 3-dimensional blood flow data, derived from computational fluid dynamics and 4-dimensional flow magnetic resonance imaging, and provide new, promising hemodynamic markers. In patients with palliated single-ventricular heart defects, the Fontan circulation passively directs systemic venous return to the pulmonary circulation in the absence of a functional subpulmonary ventricle. Therefore, the Fontan circulation is highly dependent on favorable flow and energetics, and minimal energy loss is of great importance. A focus on reducing energy loss led to the introduction of the total cavopulmonary connection (TCPC) as an alternative to the classical Fontan connection. Subsequently, many studies have investigated energy loss in the TCPC, and energy-saving geometric factors have been implemented in clinical care. Great advances have been made in computational fluid dynamics modeling and can now be done in 3-dimensional patient-specific models with increasingly accurate boundary conditions. Furthermore, the implementation of 4-dimensional flow magnetic resonance imaging is promising and can be of complementary value to these models. Recently, correlations between energy loss in the TCPC and cardiac parameters and exercise intolerance have been reported. Furthermore, efficiency of blood flow through the TCPC is highly variable, and inefficient blood flow is of clinical importance by reducing cardiac output and increasing central venous pressure, thereby increasing the risk of experiencing the well-known Fontan complications. Energy loss in the TCPC will be an important new hemodynamic parameter in addition to other well-known risk factors such as pulmonary vascular resistance and can possibly be improved by patient-specific surgical design. This article describes the theoretical background of mechanical energy of blood flow in the cardiovascular system and the methods of calculating energy loss, and it gives an overview of geometric factors associated with energy efficiency in the TCPC and its implications on clinical outcome. Furthermore, the role of 4-dimensional flow magnetic resonance imaging and areas of future research are discussed.

Stress increases intracardiac 4D flow cardiovascular magnetic resonance -derived energetics and vorticity and relates to VO2max in Fontan patients.

BACKGROUND: We hypothesize that dobutamine-induced stress impacts intracardiac hemodynamic parameters and that this may be linked to decreased exercise capacity in Fontan patients. Therefore, the purpose of this study was to assess the effect of pharmacologic stress on intraventricular kinetic energy (KE), viscous energy loss (EL) and vorticity from four-dimensional (4D) Flow cardiovascular magnetic resonance (CMR) imaging in Fontan patients and to study the association between stress response and exercise capacity. METHODS: Ten Fontan patients underwent whole-heart 4D flow CMR before and during 7.5 µg/kg/min dobutamine infusion and cardiopulmonary exercise testing (CPET) on the same day. Average ventricular KE, EL and vorticity were computed over systole, diastole and the total cardiac cycle (vorticity_volavg cycle, KEavg cycle, ELavg cycle). The relation to maximum oxygen uptake (VO2 max) from CPET was tested by Pearson's correlation or Spearman's rank correlation in case of non-normality of the data. RESULTS: Dobutamine stress caused a significant 88 ± 52% increase in KE (KEavg cycle: 1.8 ± 0.5 vs 3.3 ± 0.9 mJ, P < 0.001), a significant 108 ± 49% increase in EL (ELavg cycle: 0.9 ± 0.4 vs 1.9 ± 0.9 mW, P < 0.001) and a significant 27 ± 19% increase in vorticity (vorticity_volavg cycle: 3441 ± 899 vs 4394 ± 1322 mL/s, P = 0.002). All rest-stress differences (%) were negatively correlated to VO2 max (KEavg cycle: r = - 0.83, P = 0.003; ELavg cycle: r = - 0.80, P = 0.006; vorticity_volavg cycle: r = - 0.64, P = 0.047). CONCLUSIONS: 4D flow CMR-derived intraventricular kinetic energy, viscous energy loss and vorticity in Fontan patients increase during pharmacologic stress and show a negative correlation with exercise capacity measured by VO2 max.

Risk of Clinically Relevant Pericardial Effusion After Pediatric Cardiac Surgery.

Pericardial effusion (PE) after pediatric cardiac surgery is common. Because of the lack of a uniform classification of the presence and severity of PE, we evaluated PE altering clinical management: clinically relevant PE. Risk factors for clinically relevant PE were studied. After cardiac surgery, children were followed until 1 month after surgery. Preoperative variables were studied in the complete cohort. Perioperative and postoperative variables were studied in a case-control manner. Patients with and without clinically relevant PE were matched on age, gender, and diagnosis severity in a 1:1 ratio. Multivariate analysis was conducted using important preoperative variables from the complete cohort combined with perioperative and postoperative variables from the case-control data. 1241 surgical episodes in 1031 patients were included. Clinically relevant PE developed in 136 episodes (11.0%). Multivariate correlation with the outcome was present for age, BSA (adjusted odds ratio: 1.6, 95% CI 0.9-2.8), right-sided heart defect (adjusted odds ratio: 1.3, 95% CI 0.9-1.9), history of previous operation (adjusted odds ratio: 0.5, 95% CI 0.3-0.7), cardiopulmonary bypass use (adjusted odds ratio: 2.1, 95% CI 0.9-4.5), duration of CPAP postoperatively, and an inotropic score (adjusted odds ratio: 1.01, 95% CI 0.998-1.03). In this large patient cohort, 11.0% of postoperative periods of pediatric cardiac surgery were complicated by PE requiring alteration of treatment. Secondly, we newly identified cardiopulmonary bypass use and right-sided heart defects as risk factors for clinically relevant PE and confirmed previously described risk factors: age, CPAP duration, BSA, and inotropic score and a previously described risk reductor: history of previous operation.

Nikaidoh vs Réparation à l'Etage Ventriculaire vs Rastelli.

This review describes the different surgical options for transposition of the great arteries, ventricular septal defect (VSD), and left ventricular outflow tract obstruction. When the pulmonary valve can be used, an arterial switch operation with VSD closure and resection of pulmonary stenosis may be possible. This is not the scope of our review: we focus on the Rastelli, REV (Réparation à l'Etage Ventriculaire), and Nikaidoh techniques, and we also describe the "en bloc rotation" technique. Each of these procedures has a different history, and these techniques have not been used uniformly around the world. We describe the advantages and disadvantages of each technique together with their outcomes as reported in the literature. Some forms of transposition of the great arteries, VSD, and left ventricular outflow tract obstruction can only be corrected by the Nikaidoh operation, although this operation can be definitely contraindicated in other instances. Surgical eras and length of follow-up are not the same for all procedures, and there has been surgical bias in choosing 1 technique over another. This makes comparison between techniques difficult, although certain trends are observed.

Preoperative thresholds for mid-to-late haemodynamic and clinical outcomes after pulmonary valve replacement in tetralogy of Fallot.

AIMS: The right ventricle (RV) remodels early after pulmonary valve replacement (PVR) in tetralogy of Fallot (TOF) patients. Previously reported preoperative thresholds to achieve early postoperative RV normalization were consistently close to 80 mL/m(2) for end-systolic volume (ESV) and 160 mL/m(2) for end-diastolic volume (EDV). Our objective was to determine whether these thresholds were also associated with mid-to-late RV normalization and clinical events. METHODS AND RESULTS: Out of a multicentre cohort of 157 TOF patients who had undergone PVR, in 65 patients (62% male, age 29 ± 8 years, homograft in 98%) cardiovascular magnetic resonance (CMR) imaging was performed preoperatively and >3 years (6.3 years, interquartile range: 4.9-9.5) postoperatively. Mid-to-late haemodynamic outcome was classified as: 'RV normalization' [RV ejection fraction (EF) > 48% and RV EDV < 108 mL/m(2)] in 14 of 65 (22%) patients, 'intermediate' in 34 of 65 (52%) patients, and 'suboptimal' (RV EF < 45% and RV EDV > 120 mL/m(2)) in 17 of 65 (26%) patients. Preoperative RV ESV < 80 mL/m(2) was strongly associated with favourable mid-to-late haemodynamic outcome in a proportional odds model [common odds ratio (OR): 0.04 for worse class, 95% confidence interval (CI): 0.01-0.17]. During 7.8 ± 4.0 years follow-up after PVR, adverse clinical events (death, sustained ventricular tachycardia, or heart failure) occurred in 18 of 106 (17%) patients with preoperative CMR available. Patients with preoperative RV ESV > 95 mL/m(2) were at increased risk for unfavourable mid-to-late haemodynamic outcome (common OR: 25.5, 95% CI: 5.35-122) and events (hazard ratio: 2.89, 95% CI: 1.03-8.11). CONCLUSION: In TOF patients who had undergone PVR, the best preoperative threshold to achieve mid-to-late RV normalization was RV ESV < 80 mL/m(2). Patients with preoperative RV ESV > 95 mL/m(2) were at increased risk for suboptimal haemodynamic outcome and adverse clinical events. Our findings may assist in timing of PVR.

Characterization and improved quantification of left ventricular inflow using streamline visualization with 4DFlow MRI in healthy controls and patients after atrioventricular septal defect correction.

PURPOSE: To evaluate trans-left atrioventricular valve (LAVV) blood flow and optimize left ventricular inflow quantification in healthy controls and patients after atrioventricular septal defect (AVSD) correction. MATERIALS AND METHODS: Twenty-five patients after AVSD correction and 25 controls underwent 4DFlow MRI. Using streamline visualization in four- and two-chamber views, inflow direction at early and late filling was defined at the annulus level and at the peak inflow velocity (PIV) level. Trans-LAVV flow volume and velocity were assessed from a static 2D-multiplanar-reformat (MPR), a 4D-MPR tracking LAVV annulus and a 4D-MPR tracking the PIV-level, angulated perpendicular to the inflow. RESULTS: In patients, on average 9° more laterally directed inflow was found at the PIV-level compared to controls. In controls, 4DFlow velocity mapping with LAVV annulus tracking resulted in lower absolute error with aortic flow (3 (1-8) mL) than with static 2D-MPR (7 (4-16) mL, P = 0.001). In patients, 4D-MPR tracking the PIV-level, resulted in lower absolute error with aortic flow (2 (1-4) mL) than with 4D-MPR LAVV annulus tracking (6 (2-10) mL, P = 0.003). CONCLUSION: Streamline visualization of 4DFlow MRI data revealed dynamic trans-LAVV inflow and more lateral flow after AVSD correction. Streamline visualization improved trans-LAVV flow quantification as the positioning and angulation of the measurement plane was optimized, allowing an accurate assessment of left ventricular inflow.

Characterization and quantification of dynamic eccentric regurgitation of the left atrioventricular valve after atrioventricular septal defect correction with 4D Flow cardiovascular magnetic resonance and retrospective valve tracking.

BACKGROUND: To characterize and directly quantify regurgitant jets of left atrioventricular valve (LAVV) in patients with corrected atrioventricular septal defect (AVSD) by four-dimensional (4D)Flow Cardiovascular Magnetic Resonance (CMR), streamline visualization and retrospective valve tracking. METHODS: Medical ethical committee approval and informed consent from all patients or their parents were obtained. In 32 corrected AVSD patients (age 26 ± 12 years), echocardiography and whole-heart 4DFlow CMR were performed. Using streamline visualization on 2- and 4-chamber views, the angle between regurgitation and annulus was followed throughout systole. On through-plane velocity-encoded images reformatted perpendicular to the regurgitation jet the cross-sectional jet circularity index was assessed and regurgitant volume and fraction were calculated. Correlation and agreement between different techniques was performed with Pearson's r and Spearman's rho correlation and Bland-Altman analysis. RESULTS: In 8 patients, multiple regurgitant jets over the LAVV were identified. Median variation in regurgitant jet angle within patients was 36°(IQR 18-64°) on the 2-chamber and 30°(IQR 20-40°) on the 4-chamber. Regurgitant jets had a circularity index of 0.61 ± 0.16. Quantification of the regurgitation volume was feasible with 4DFlow CMR with excellent correlation between LAVV effective forward flow and aortic flow (r = 0.97, p < 0.001) for internal validation and moderate correlation with planimetry derived regurgitant volume (r = 0.65, p < 0.001) and echocardiographic grading (rho = 0.51, p = 0.003). CONCLUSIONS: 4DFlow CMR with streamline visualization revealed multiple, dynamic and eccentric regurgitant jets with non-circular cross-sectional shape in patients after AVSD correction. 4DFlow with retrospective valve tracking allows direct and accurate quantification of the regurgitation of these complex jets.

Cathether-based interventional strategies for cor triatriatum in the adult - feasibility study through a hybrid approach.

BACKGROUND: Cor triatriatum is a rare congenital cardiac abnormality, consisting of an obstructing membrane between the pulmonary veins and the mitral valve in varying patterns. The entitiy can mimick the pathophysiology of mitral stenosis, necessitating surgical resection. Occasionally, percutaneous balloon dilatation of the membrane has been successfully performed. CASE PRESENTATION: We report two cases with cor triatriatum where intraoperative balloon dilatation of the membrane was attempted followed by surgical resection, to explore the feasibility of cathether-based interventional strategies for cor triatriatum. CONCLUSIONS: Various anatomical variations exist of cor triatriatum, depending on the drainage of the pulmonary veins and the drainage of the proximal chamber in the right or left atrium. Only isolated forms of cor triatriatum where all pulmonary veins ultimately drain into the left atrium can be recommended for percutaneous strategies. In addition, several anatomical characteristics should be considered to predict technical success of cathether-based interventional strategies, such as the location of the membrane, the degree of pulmonary vein stenosis, the extent of calcification, and the presence of other (congenital) cardiovascular abnormalities. Furthermore, long-term efficacy of these strategies remains to be confirmed. As such, surgical treatment of cor triatriatum remains the mainstay of treatment in adult patients, especially when other cardiovascular anomalies are present which require surgical correction.