Indications and timing of pulmonary valve replacement after tetralogy of Fallot repair

Longitudinal ECG changes in tetralogy of Fallot and association with surgical repair

Background

ECG abnormalities have been linked to adverse changes in right ventricular (RV) morphology and poor clinical outcomes in repaired Tetralogy of Fallot (rTOF). Our aim was to describe how ECG changes progress in early and intermediate follow-up and whether types of surgical strategy at the time of primary repair affected these changes.

Methods

We studied patients with rTOF born 2000-2018 operated at our institution. Seven time points in relation to primary repair, follow-up, and pulmonary valve replacement (PVR) were identified. Patients correct with valve sparing repair (VSR), trans-annular patch (TAP) including with a monocusp valve (TAP + M) and with at least 3 ECGs were included. PQ interval, QRS duration, dispersion, and fragmentation, QTc duration and dispersion, JTc as well as presence of a right bundle branch block (RBBB) were analyzed. Medical records were reviewed for demographic and surgical data.

Results

Two hundred nineteen patients with 882 ECGs were analyzed with a median follow-up time of 12.3 years (8.4, 17) with 41 (19%) needing PVR during the study period. QRS duration increased at time of primary repair to discharge from 66 msec (IQR 12) to 129 msec (IQR 27) (p < 0.0001) and at 1- and 6- year follow-up but showed only a modest and temporary decrease after PVR. QTc increased at the time of primary repair as well as prior to PVR. PQ interval showed a small increase at the time of primary repair, was at its highest prior to PVR and decreased with PVR. Type of surgical repair affected mainly QTc and JTc and was consistently longer in the TAP + M group until PVR. In VSR, QTc and JTc were prolonged initially compared to TAP but were similar after 1 year. After PVR, there were no differences in adverse ECG changes between surgical groups.

Conclusions

PQ interval and QRS duration best correspond to the assumed volume load whereas the relationship with QTc and JTc is more complex, suggesting that these represent more complex remodeling of the myocardium. Before PVR, QTc and JTc are longer in the TAP + M group which may be due to a longer surgical incision.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Optimizing percutaneous pulmonary valve implantation with patient-specific 3D-printed pulmonary artery models and hemodynamic assessment

Background

Percutaneous pulmonary valve implantation (PPVI) has emerged as a less invasive alternative for treating severe pulmonary regurgitation after tetralogy of Fallot (TOF) repair in patients with a native right ventricular outflow tract (RVOT). However, the success of PPVI depends on precise patient-specific valve sizing, the avoidance of oversizing complications, and optimal valve performance. In recent years, innovative adaptations of commercially available cardiovascular mock loops have been used to test conduits in the pulmonary position. These models are instrumental in facilitating accurate pulmonic valve sizing, mitigating the risk of oversizing, and providing insight into the valve performance before implantation. This study explored the utilization of custom-modified mock loops to implant patient-specific 3D-printed pulmonary artery geometries, thereby advancing PPVI planning and execution.

Material and Methods

Patient-specific 3D-printed pulmonary artery geometries of five patients who underwent PPVI using Pulsta transcatheter heart valve (THV) ® were tested in a modified ViVitro pulse duplicator system®. Various valve sizes were subjected to 10 cycles of testing at different cardiac output levels. The transpulmonary systolic and regurgitation fractions of the valves were also recorded and compared.

Results

A total of 39 experiments were conducted using five different patient geometries and several different valve sizes (26, 28, 30, and 32 mm) at 3, 4, and 5 L/min cardiac output at heart rates of 70 beats per minute (bpm) and 60/40 systolic/diastolic ratios. The pressure gradients and regurgitation fractions of the tested valve sizes in the models were found to be similar to the pressure gradients and regurgitation fractions of valves used in real procedures. However, in two patients, different valve sizes showed better hemodynamic values than the actual implanted valves.

Discussion

The use of 3D printing technology, electromagnetic flow meters, and the custom-modified ViVitro pulse duplicator system® in conjunction with patient-specific pulmonary artery models has enabled a comprehensive assessment of percutaneous pulmonic valve implantation performance. This approach allows for accurate valve sizing, minimization of oversizing risks, and valuable insights into hemodynamic behavior before implantation. The data obtained from this experimental setup will contribute to advancing PPVI procedures and offer potential benefits in improving patient outcomes and safety.

Catheter-based Interventions in Tetralogy of Fallot Across the Lifespan

Surgical treatment of tetralogy of Fallot (TOF) involves surgical relief of right ventricular outflow tract (RVOT) obstruction and closure of ventricular septal defect. However, some patients may require staged palliation before surgical repair. This traditionally was achieved only with surgery but recently evolved to include catheter-based techniques. RVOT dysfunction occurs inevitably after the surgical repair of TOF and, depending on the surgical approach, manifests as either progressive stenosis, regurgitation, or a combination of both. This predisposes the individual to repeated RVOT interventions with the attendant risks of multiple open-heart surgeries. The advent of transcatheter pulmonary valve replacement has reduced the operative burden, and the expansion of transcatheter pulmonary valve replacement device platforms has widened the type and size of RVOT anatomies that can be treated. This review will discuss the transcatheter therapies available throughout the lifespan of the patient with TOF.

Right Heart Remodeling After Pulmonary Valve Replacement in Patients With Pulmonary Atresia or Critical Stenosis With Intact Ventricular Septum

Background Patients with pulmonary atresia or critical pulmonary stenosis with intact ventricular septum (PA/IVS) and biventricular circulation may require pulmonary valve replacement (PVR). Right ventricular (RV) remodeling after PVR is well described in tetralogy of Fallot (TOF); we sought to investigate RV changes in PA/IVS using cardiac magnetic resonance imaging. Methods and Results A retrospective cohort of patients with PA/IVS who underwent PVR at Boston Children's Hospital from 1995 to 2021 with cardiac magnetic resonance imaging before and after PVR was matched 1:3 with patients with TOF by age at PVR. Median regression modeling was performed with post-PVR indexed RV end-diastolic volume as the primary outcome. A total of 20 patients with PA/IVS (cases) were matched with 60 patients with TOF (controls), with median age at PVR of 14 years. Pre-PVR indexed RV end-diastolic volume was similar between groups; cases had higher RV ejection fraction (51.4% versus 48.6%; P=0.03). Pre-PVR RV free wall and left ventricular (LV) longitudinal strain were similar, although LV midcavity circumferential strain was decreased in cases (-15.6 versus -17.1; P=0.001). At a median of 2 years after PVR, indexed RV end-diastolic volume was similarly reduced; cases continued to have higher RV ejection fraction (52.3% versus 46.9%; P=0.007) with less reduction in RV mass (Δ4.5 versus 9.6 g/m2; P=0.004). Post-PVR, RV and LV longitudinal strain remained unchanged, and LV circumferential strain was similar, although lower in cases. Conclusions Compared with patients with TOF, patients with PA/IVS demonstrate similar RV remodeling after PVR, with lower reduction in RV mass and comparatively higher RV ejection fraction. Although no differences were detected in peak systolic RV or LV strain values, further investigation of diastolic parameters is needed.

ACR Appropriateness Criteria® Congenital or Acquired Heart Disease

Pediatric heart disease is a large and diverse field with an overall prevalence estimated at 6 to 13 per 1,000 live births. This document discusses appropriateness of advanced imaging for a broad range of variants. Diseases covered include tetralogy of Fallot, transposition of great arteries, congenital or acquired pediatric coronary artery abnormality, single ventricle, aortopathy, anomalous pulmonary venous return, aortopathy and aortic coarctation, with indications for advanced imaging spanning the entire natural history of the disease in children and adults, including initial diagnosis, treatment planning, treatment monitoring, and early detection of complications. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Pulmonary valve reconstruction for acquired pulmonary regurgitation in patients with treated congenital heart disease

OBJECTIVES

Pulmonary valve regurgitation is a common problem after relief of right ventricular outflow tract (RVOT) obstruction with a transannular patch. Pulmonary valve replacement with a homograft or xenograft is the routine treatment. Longevity of biological valves and the availability of homografts are limited. Alternatives to restore RVOT competence are evaluated. The goal of this study was to present intermediate-term results for pulmonary valve reconstruction (PVr) in patients with severe regurgitation.

METHODS

PVr was performed in 24 patients (August 2006‒July 2018). We analysed perioperative data, pre- and postoperative cardiac magnetic resonance (CMR) imaging studies, freedom from valve replacement and risk factors for pulmonary valve dysfunction.

RESULTS

The underlying diagnoses were tetralogy of Fallot (n = 18, 75%), pulmonary stenosis (n = 5, 20.8%) and the double outlet right ventricle post banding procedure (n = 1, 4.2%). The median age was 21.5 (14.8-23.7) years. Main (n = 9, 37.5%) and branch pulmonary artery procedures (n = 6, 25%) and surgery of the RVOT (n = 16, 30.2%) were often part of the reconstruction. The median follow-up after the operation was 8.0 (4.7-9.7) years. Freedom from valve failure was 96% at 2 and 90% at 5 years. The mean longevity of the reconstructive surgery was 9.9 years (95% confidence interval: 8.8-11.1 years). CMR before and 6 months after surgery showed a reduction in the regurgitation fraction [41% (33-55) vs 20% (18-27) P = 0.00] and of the indexed right ventricular end-diastolic volume [156 ml/m2 (149-175) vs 116 ml/m2 (100-143), P = 0.004]. Peak velocity across the pulmonary valve (determined by CMR) half a year after surgery was 2.0, unchanged.

CONCLUSIONS

PVr can be achieved with acceptable intermediate-term results and may delay pulmonary valve replacement.

Impact of pulmonary valve replacement on left and right ventricular function using strain analysis, in children with repaired tetralogy of Fallot

BACKGROUND

In repaired Tetralogy of Fallot (rTOF), pulmonary regurgitation and resulting right ventricular (RV) and left ventricular (LV) dysfunction are associated with adverse clinical outcomes. We performed an echocardiographic assessment of LV and RV function using Global Longitudinal Strain (GLS) and conventional echo method prior to and following Pulmonary Valvular Replacement (PVR) to help inform proper timing of operation.

RESULTS

A total of 30 rTOF patients (12.17 ± 2.5 years, 70% male) were included. Regarding to LV function, the study revealed a significant reverse correlation between LV GLS (absolute value) and early (mean = 10.4 days) and late (mean = 7.4 months) postop LVEF. Paired T-Test showed significant difference between GLS of LV and RV before and late after operation (op), however, without significant changes early postop. Late postop significant improvements occurred in other conventional echo indices of LV and RV function as well. There was also a significant correlation between echo-measured LVEF & Fraction Area Change (RV FAC) and MRI-derived LVEF & RVEF, respectively.

CONCLUSION

In this cross-sectional study in rTOF patients, RV and LV GLS as well as conventional echocardiographic indices regarding LV and RV function improved significantly after 6 months (mean = 7.4mo) following PVR.

Conal Septal Hypoplasia in Tetralogy of Fallot-Impact on Clinical Course, Treatment Strategies, and Outcomes After Surgical Intervention

We sought to characterize the clinical course and outcomes of intervention for Tetralogy of Fallot (TOF) with associated conal septal hypoplasia (CSH) compared to those with identifiable conal septum on initial newborn echocardiogram. We performed a retrospective, 1:2 case-control study of children with TOF anatomy, 33 with CSH and 66 with typical TOF, who underwent surgical repair from 1991-2019 at Children's Wisconsin. Data on echocardiographic anatomic features, systemic oxygen saturations, medical therapies, admissions, palliative interventions, operative strategies, and long-term follow-up were compared. The CSH group had fewer hypercyanotic spells (6% vs 42%, p < 0.001), beta-blockers prescribed (12% vs 41%, p = 0.005), and hospital admissions for cyanosis (12% vs 44%; p = 0.001) prior to any intervention. Of 14 who required palliative intervention, 8 had balloon pulmonary valvuloplasty (BPV) (7 from the CSH group and 1 from the control group), and 6 had systemic-to-pulmonary artery shunts (all from the control group). Definitive repair was performed at a significantly older age in the CSH group (10.2 ± 10 vs 5.6 ± 5.9 months, p = 0.011), with less subpulmonary muscle resection (57.6% in vs 92.4%, p < 0.001) and higher use of a transannular patch (84.8% vs 65.2%, p = 0.040). The average time to surgical reintervention was similar in both groups (9.7 ± 5.9 vs 8.6 ± 6.4 years in controls). We conclude that infants with TOF and CSH have a milder preoperative clinical course with fewer hypercyanotic spells or need for medical therapy. They also respond well to palliative BPV and can safely undergo later definitive repair compared to typical TOF with a well-developed conal septum.

Characterization of Favorable Right Ventricular Dimensions for Optimal Reverse Remodeling following Pulmonary Valve Replacement

OBJECTIVE

We sought to couple current cardiac magnetic resonance (CMR) thresholds of right ventricular (RV) size and function with longitudinal trajectories of RV recovery, after pulmonary valve replacement (PVR). We aimed to identify optimal timing of PVR and couple CMR-based metrics with contemporaneous echocardiographic metrics.

METHODS

From 6/2002 to 1/2019, 174 patients with severe pulmonary regurgitation and peak RV outflow tract gradient <30 mmHg underwent PVR at Cleveland Clinic. Mean age was 35±16 years and 60 (34%) had concomitant tricuspid valve surgery. RV end diastolic area index (RVEDAi) and function metrics were measured by offline image review on preoperative and 794 postoperative echocardiograms. Contemporaneous RV end diastolic volume index (RVEDVi) was assessed on CMR and correlated to RVEDAi. Multiphase nonlinear mixed-effects models were used to analyze the longitudinal change in RV size and function after PVR.

RESULTS

RVEDAi was correlated with RVEDVi (P<.0001, r=.59). RVEDAi decreased slowly over 10 years following PVR. An inflection point at 24 cm²/m² was noted at 1 year post-PVR and was associated with failure of RV reverse remodelling and RVEDVi ≥ 150 ml/m². Compared to patients with preoperative RVEDVi ≥ 150 mL/m², patients with RVEDVi < 150 mL/m² had accelerated recovery of longitudinal trajectories of RV size and function metrics on echocardiograms.

CONCLUSION

Reverse remodeling of RV following PVR is an ongoing process. Current accepted threshold values for PVR are associated with greatest RV recovery, suggesting that earlier PVR is warranted. Echocardiography can potentially be utilized in lieu of CMR for surveillance and interventional triage.

The Use of Automated Atrial CMR Measures and a Novel Atrioventricular Coupling Index for Predicting Risk in Repaired Tetralogy of Fallot

Atrial size and function have been recognized as markers of diastolic function, and diastolic dysfunction has been identified as a predictor of adverse outcomes in repaired tetralogy of Fallot (rTOF). This was a retrospective single-center study with the objective of investigating the use of atrial measurements obtained via CMR for predicting outcomes in rTOF patients. Automated contours of the left and right atria (LA and RA) were performed. A novel parameter, termed the Right Atrioventricular Coupling Index (RACI), was defined as the ratio of RA end-diastolic volume to right ventricle (RV) end-diastolic volume. Patients were risk-stratified using a previously validated Importance Factor Score for the prediction of life-threatening arrhythmias in rTOF. Patients with a high-risk Importance Factor Score (>2) had a significantly larger minimum RA volume (p = 0.04) and RACI (p = 0.03) compared to those with scores ≤2. ROC analysis demonstrated RACI to be the best overall predictor of a high-risk Importance Factor Score (AUC 0.73, p = 0.03). Older age at the time of repair and a diagnosis of pulmonary atresia were associated with a larger RACI. Automated atrial CMR measurements are easily obtained from standard CMRs and have the potential to serve as noninvasive predictors of adverse outcomes in rTOF.

Evaluation of right ventricle systolic function after tetralogy of Fallot repair: A systematic review comparing cardiac magnetic resonance and global longitudinal strain

BACKGROUND

Most patients who undergo tetralogy of Fallot (TOF) repair experience late right ventricle (RV) dysfunction due to pulmonary valve regurgitation (PVR). Cardiac magnetic resonance (CMR) is the gold standard method for evaluating RV during follow-up. Global longitudinal strain (GLS) has been introduced as a novel method for the assessment of RV dysfunction. We aimed to compare the feasibility of GLS and CMR for assessing RV function after TOF repair.

METHODS

We systematically reviewed the English literature using PubMed, SciELO and Google Scholar for articles published between January 1, 2015, and December 31, 2020. Articles evaluating RV function comparing by GLS and CMR after TOF repair were included.

RESULTS

Nine studies including 465 patients were analyzed. Most patients were men (280; 60%), the male:female ratio was 1.5:1, and the age range was .8 to 57.7 years. The mean follow-up time was 6 to 32 months. The correlation between RV GLS and RV ejection fraction (EF) by CMR was negative for the articles and varied from moderate to strong (r = -.45, r = -.60, r = -.76).

CONCLUSION

Right ventricle GLS can be considered for routine follow-up of TOF repair patients, even though CMR remains the noninvasive gold standard method. Using a single parameter may not allow comparison of the accuracy of 3D RV EF by using CMR and GLS. Further studies with a larger number of patients undergoing TOF repair are required to evaluate the correlation between these examinations.

Single-Centre Case Series Assessment of Early Exercise Capacity Data Among Patients Who Received an Alterra Prestent and SAPIEN 3 Valve Placement

Previous studies have used cardiopulmonary exercise test (CPET) data to objectively assess physiological changes in patients undergoing percutaneous pulmonary valve implantation. A retrospective review was performed to assess pre- and post-CPET data among patients undergoing Alterra Adaptive Prestent and SAPIEN 3 transcatheter heart valve (Alterra) placement. Of the 7 patients eligible for the study, 5 (71%) were male. The mean age was 22 years (range: 12-49 years). CPET data showed significant (P = 0.03) improvement in ventilatory efficiency (VE/VCO2) while only 2 (29%) patients had an improvement of percent predicted peak oxygen consumption (VO2). These findings suggest favourable haemodynamic changes though further investigation is needed.

Role of Cardiovascular Magnetic Resonance in Native Valvular Regurgitation: A Comprehensive Review of Protocols, Grading of Severity, and Prediction of Valve Surgery

Valvular regurgitation is common in developed countries with an increasing prevalence due to the aging of the population and more accurate diagnostic imaging methods. Echocardiography is the gold standard method for the assessment of the severity of valvular heart regurgitation. Nonetheless, cardiovascular magnetic resonance (CMR) has emerged as an additional tool for assessing mainly the severity of aortic and mitral valve regurgitation in the setting of indeterminate findings by echocardiography. Moreover, CMR is a valuable imaging modality to assess ventricular volume and flow, which are useful in the calculation of regurgitant volume and regurgitant fraction of mitral valve regurgitation, aortic valve regurgitation, tricuspid valve regurgitation, and pulmonary valve regurgitation. Notwithstanding this, reference values and optimal thresholds to determine the severity and prognosis of valvular heart regurgitation have been studied lesser by CMR than by echocardiography. Hence, further larger studies are warranted to validate the potential prognostic relevance of the severity of valvular heart regurgitation determined by CMR. The present review describes, analyzes, and discusses the use of CMR to determine the severity of valvular heart regurgitation in clinical practice.

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.

Comparison of semi-automated versus manual quantitative right ventricular assessment in tetralogy of Fallot

BACKGROUND

Tetralogy of Fallot is a congenital heart defect diagnosed in infancy. Assessment of right ventricular size and function is important for evaluation of patients with tetralogy of Fallot, but these quantitative measures are challenging by echocardiography. This study evaluates a semi-automated software (EchoInsight®, Epsilon Imaging) by comparing its measures to manual measures in children with tetralogy of Fallot.

METHODS

Echocardiographic measurements were performed using manual techniques and semi-automated software. Right ventricular measurements included end-diastolic and end-systolic area, fractional area change, chamber dimensions, and tricuspid annular plane systolic excursion. Reliability, correlation, and agreement between manual and semi-automated measures were assessed.

RESULTS

Echocardiograms for 46 patients were analysed. Intra- and inter-observer reliabilities for semi-automated measures were good with intraclass correlation coefficients all over 0.95 and 0.85, respectively. There was high correlation between manual and semi-automated methods for areas and dimensions (r = 0.91-0.98). Tricuspid annular plane systolic excursion measures and fractional area change also correlated, albeit less strongly. The semi-automated measurements of end-systolic and end-diastolic area were a 20 and 47% higher than manual methods, respectively.The semi-automated method yielded a relative 52% lower fractional area change compared to the manual method.

CONCLUSIONS

The semi-automated software generates quantitative right ventricular measures in children with tetralogy of Fallot with good reliability and good correlation with manual methods for all measures, but with significant difference between manual and semi-automated techniques for area and functional measures. The specific right ventricular geometry in tetralogy of Fallot children may be why, compared to normal anatomy, greater differences were observed between the two techniques.

Avalanches in cardiology

Sudden cardiac death (SCD) accounts for 15%–60% of mortality in patients with heart disease. Generally, this has been attributed to ventricular tachyarrhythmia. However, ventricular tachyarrhythmia has been documented or strongly suspected on clinical grounds in a relatively small proportion of SCD patients (8%–50%). Attempted prophylaxis of SCD by implantation of cardioverter-defibrillator is associated with variable success in different subsets of high-risk cardiac patients (30%–70%). A significant number of SCD, therefore, appear to be due to catastrophic circulatory failure. Multiple interdependent compensatory mechanisms help to maintain circulation in advanced cardiac disease. Rapid, unexpected, and massive breakdown of the compensated state can be precipitated by small and often imperceptible triggers. The initial critical but stable state followed by rapid circulatory failure and death has been considered to be analogous to snow avalanches. It is typically described in patients with left ventricular (LV) dysfunction (ischemic or nonischemic). It is now recognized that SCD can also happen in conditions where the right ventricle (RV) takes the brunt of the hemodynamic load. Advanced pulmonary arterial hypertension and operated patients of tetralogy of Fallot with pulmonary regurgitation are of particular interest to pediatric cardiologists. A large amount of data is available on LV changes and mechanics, while relatively little information is available on the mechanisms of RV adaptation to increased load and RV failure. Whether the triggers and the decompensatory processes are similar for the two ventricles is a moot point. This article highlights the currently available knowledge on the pathophysiology of SCD in RV overload states, with special reference to RV adaptive and decompensatory mechanisms, and therapeutic measures that can potentially interrupt the vicious downward course (cardiac avalanches).

Early experience with surgical strategies aimed at preserving the pulmonary valve and annulus during repair of tetralogy of Fallot

Background :

During repair of tetralogy of fallot (TOF) we modified surgical strategies to preserve the valve and annulus if the pulmonary valve leaflets are pliable and not significantly dysplastic.

Methods :

Initially, the repair was done from the main pulmonary artery (Group-1, 215 patients) and later through an additional incision in the infundibulum of the right ventricle (Group-2, 73 patients). Recently, we changed the approach to commissurotomy of the fused leaflets by releasing the supra valvar tethering and delamination of the cuspal apparatus till the base to improve the mobility of the cusps and do a controlled commissurotomy (Group-3, 14 patients). With delamination, we could extend the limit of the repair to a z-score of –3.5.

Results :

There was no hospital mortality; two patients died at home after discharge. A mean follow-up of 42.01 months ± 19.25 is available for 198 patients (92%) for group 1, 16.03 ± 7.45 for group 2, and 4.07 ± 2.09 for group 3. The re-intervention-free survival is 94.4% in group 1. The z value improved from -3 (-3–-2) to -1.2 (-3 – 0), P = 0.001 in Group 1, from -2.8 (-3–-2.4) to -1 (-1.1–-0.7), P = 0.001 in Group 2 and from –3 (-4–-3) to -1, P = 0.001 in Group 3. In all the groups, there was trivial or mild pulmonary regurgitation.

Conclusions :

During repair of TOF, adequate valve/annulus sparing is possible if the repair is done from both the main pulmonary artery and infundibular incisions using the delamination technique.

Biventricular Global Function Index Is Associated With Adverse Outcomes in Repaired Tetralogy of Fallot

INTRODUCTION

Cardiac magnetic resonance (CMR) derived biventricular global function index (BVGFI) is a new CMR parameter that integrates biventricular volumes, mass, and function using clinically available CMR parameters. The associations of BVGFI with clinical outcomes in repaired tetralogy of Fallot are unknown.

METHODS

Patients with repaired tetralogy of Fallot who had a CMR before the occurrence of a composite outcome of death, resuscitated sudden death, or sustained ventricular tachycardia were studied. BVGFI was calculated as the average of right and left GFI. GFI was defined as (ventricular stroke volume×100)/(ventricular mean cavity volume + total ventricular myocardial volume). Ventricular mean cavity volume was defined as ([end-diastolic + end-systolic volume]/2). Cox multivariable regression analysis and classification and regression tree methodology were used.

RESULTS

Of the 736 eligible subjects (mean age at CMR 25.4±14.5 years), with a median follow-up of 28 months, 55 subjects (7.4%) reached the composite outcome (46 deaths and 9 sustained ventricular tachycardia). Independent associations with the composite outcome were as follows: BVGFI <37 (hazard ratio, 2.52; P=0.004), right ventricular end-systolic volume index >85 mL/m² (hazard ratio, 3.25; P<0.001), atrial tachycardia (hazard ratio, 2.03; P=0.021), and age at repair >2.5 years (hazard ratio, 3.37; P<0.001). Classification and regression tree analysis identified BVGFI as the most discriminatory CMR parameter associated with a high risk for adverse outcomes.

CONCLUSIONS

BVGFI, a novel CMR-derived imaging biomarker combining biventricular volumes, mass, and function, may improve risk stratification for adverse clinical outcomes in patients with repaired tetralogy of Fallot.

A geometrically adaptable heart valve replacement

Congenital heart valve disease has life-threatening consequences that warrant early valve replacement; however, the development of a growth-accommodating prosthetic valve has remained elusive. Thousands of children continue to face multiple high-risk open-heart operations to replace valves that they have outgrown. Here, we demonstrate a biomimetic prosthetic valve that is geometrically adaptable to accommodate somatic growth and structural asymmetries within the heart. Inspired by the human venous valve, whose geometry is optimized to preserve functionality across a wide range of constantly varying volume loads and diameters, our balloon-expandable synthetic bileaflet valve analog exhibits similar adaptability to dimensional and shape changes. Benchtop and acute in vivo experiments validated design functionality, and in vivo survival studies in growing sheep demonstrated that mechanical valve expansion accommodated growth. As illustrated in this work, dynamic size adaptability with preservation of unidirectional flow in prosthetic valves thus offers a paradigm shift in the treatment of heart valve disease.

Long-term outcomes following repair of truncus arteriosus and interrupted aortic arch

OBJECTIVES

We aim to evaluate the long-term outcomes following repair of truncus arteriosus with an interrupted aortic arch.

METHODS

We reviewed all children (n = 24) who underwent repair of truncus arteriosus and an interrupted aortic arch between 1979 and 2018 in a single institution. The morphology of the interrupted aortic arch was type A in 5, type B in 18 and type C in 1.

RESULTS

The median age at repair was 10 days and the median weight was 3.1 kg. Direct end-to-side anastomosis of the ascending and descending aorta was performed in 16 patients (67%, 16/24), patch augmentation in 5 patients (21%, 5/24) and direct anastomosis with the use of an interposition graft to the descending aorta in 2 patients (8%, 2/24). One patient, the first in the series, underwent interrupted aortic arch repair via subclavian flap aortoplasty prior to truncus repair. A period of deep hypothermic circulatory arrest was used in 16 patients, and isolated cerebral perfusion was used in 8 patients. The early mortality rate was 17% (4 out of 24 patients). There were no late deaths and overall survival was 83 ± 8% [95% confidence interval (CI) 61-93] at 20 years. Freedom from any reoperation was 33 ± 11% (95% CI 14-54) at 5 years and 13 ± 9% (95% CI 2-34) at 10 years. Six patients underwent 10 aortic reoperations. Freedom from aortic arch reoperation was 69 ± 11% (95% CI 42-85) at 10 and 20 years. Follow-up was 95% complete (19/20), with a median follow-up time of 20 years. At last follow-up, no clinically significant aortic arch obstruction was identified in any patient, and all patients were in New York Heart Association Class I/II.

CONCLUSIONS

Repair of truncus arteriosus with an interrupted aortic arch with direct end-to-side anastomosis results in good survival beyond hospital discharge. Although the long-term functional state of patients is good, reoperation rates are high.

Computational analysis of cardiac structure and function in congenital heart disease: Translating discoveries to clinical strategies

Increased availability and access to medical image data has enabled more quantitative approaches to clinical diagnosis, prognosis, and treatment planning for congenital heart disease. Here we present an overview of long-term clinical management of tetralogy of Fallot (TOF) and its intersection with novel computational and data science approaches to discovering biomarkers of functional and prognostic importance. Efforts in translational medicine that seek to address the clinical challenges associated with cardiovascular diseases using personalized and precision-based approaches are then discussed. The considerations and challenges of translational cardiovascular medicine are reviewed, and examples of digital platforms with collaborative, cloud-based, and scalable design are provided.

The Real Need for Regenerative Medicine in the Future of Congenital Heart Disease Treatment

Bioabsorbable materials made from polymeric compounds have been used in many fields of regenerative medicine to promote tissue regeneration. These materials replace autologous tissue and, due to their growth potential, make excellent substitutes for cardiovascular applications in the treatment of congenital heart disease. However, there remains a sizable gap between their theoretical advantages and actual clinical application within pediatric cardiovascular surgery. This review will focus on four areas of regenerative medicine in which bioabsorbable materials have the potential to alleviate the burden where current treatment options have been unable to within the field of pediatric cardiovascular surgery. These four areas include tissue-engineered pulmonary valves, tissue-engineered patches, regenerative medicine options for treatment of pulmonary vein stenosis and tissue-engineered vascular grafts. We will discuss the research and development of biocompatible materials reported to date, the evaluation of materials in vitro, and the results of studies that have progressed to clinical trials.

Heart failure in adult congenital heart disease: tetralogy of Fallot

The number of rTOF patients who survive into adulthood is steadily rising, with currently more than 90% reaching the third decade of life. However, rTOF patients are not cured, but rather have a lifelong increased risk for cardiac and non-cardiac complications. Heart failure is recognized as a significant complication. Its occurrence is strongly associated with adverse outcome. Unfortunately, conventional concepts of heart failure may not be directly applicable in this patient group. This article presents a review of the current knowledge on HF in rTOF patients, including incidence and prevalence, the most common mechanisms of heart failure, i.e., valvular pathologies, shunt lesions, left atrial hypertension, primary left heart and right heart failure, arrhythmias, and coronary artery disease. In addition, we will review information regarding extracardiac complications, risk factors for the development of heart failure, clinical impact and prognosis, and assessment possibilities, particularly of the right ventricle, as well as management strategies. We explore potential future concepts that may stimulate further research into this field.

Reliability of respiratory-triggered two-dimensional cine k-adaptive-t-autocalibrating reconstruction for Cartesian sampling for the assessment of biventricular volume and function in patients with repaired tetralogy of Fallot

Objective:

To compare left ventricular (LV) and right ventricular (RV) volume, function, and image quality of a respiratory-triggered two-dimensional (2D)-cine k-adaptive-t-autocalibrating reconstruction for Cartesian sampling (2D kat-ARC) with those of the standard reference, namely, breath-hold 2D balanced steady-state free precession (2D SSFP), in patients with repaired tetralogy of Fallot (TOF).

Methods:

30 patients (14 males, mean age 32.2 ± 13.9 years) underwent cardiac magnetic resonance, and 2D kat-ARC and 2D SSFP images were acquired on short-axis view. Biventricular end-diastolic volume (EDV) and end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), and LV mass (LVM) were analysed.

Results:

The 2D kat-ARC had significantly shorter scan time (35.2 ± 9.1 s vs 80.4 ± 16.7 s; p < 0.0001). Despite an analysis of image quality showed significant impairment using 2D kat-ARC compared to 2D SSFP cine (p < 0.0001), the two sequences demonstrated no significant difference in terms of biventricular EDV, LVESV, LVSV, LVEF, and LVM. However, the RVESV was overestimated for 2D kat-ARC compared with that for 2D SSFP (73.8 ± 43.2 ml vs 70.3 ± 44.5 ml, p = 0.0002) and the RVSV and RVEF were underestimated (RVSV = 46.2±20.5 ml vs 49.4 ± 20.4 ml, p = 0.0024; RVEF = 40.2±12.7% vs. 43.5±14.0%, p = 0.0002).

Conclusion:

Respiratory-triggered 2D kat-ARC cine is a reliable technique that could be used in the evaluation of LV volumes and function.

Advances in knowledge:

2D cine kat-ARC is a reliable technique for the assessment LV volume and function in patients with repaired TOF.

Regional shape, global function and mechanics in right ventricular volume and pressure overload conditions: a three-dimensional echocardiography study

Our aim was to assess the regional right ventricular (RV) shape changes in pressure and volume overload conditions and their relations with RV function and mechanics. The end-diastolic and end-systolic RV endocardial surfaces were analyzed with three-dimensional echocardiography (3DE) in 33 patients with RV volume overload (rToF), 31 patients with RV pressure overload (PH), and 60 controls. The mean curvature of the RV inflow (RVIT) and outflow (RVOT) tracts, RV apex and body (both divided into free wall (FW) and septum) were measured. Zero curvature defined a flat surface, whereas positive or negative curvature indicated convexity or concavity, respectively. The longitudinal and radial RV wall motions were also obtained. rToF and PH patients had flatter FW (body and apex) and RVIT, more convex interventricular septum (body and apex) and RVOT than controls. rToF demonstrated a less bulging interventricular septum at end-systole than PH patients, resulting in a more convex shape of the RVFW (r = − 0.701, p < 0.0001), and worse RV longitudinal contraction (r = − 0.397, p = 0.02). PH patients showed flatter RVFW apex at end-systole compared to rToF (p < 0.01). In both groups, a flatter RVFW apex was associated with worse radial RV contraction (r = 0.362 in rToF, r = 0.482 in PH at end-diastole, and r = 0.555 in rToF, r = 0.379 in PH at end-systole, respectively). In PH group, the impairment of radial contraction was also related to flatter RVIT (r = 0.407) and more convex RVOT (r = − 0.525) at end-systole (p < 0.05). In conclusion, different loading conditions are associated to specific RV curvature changes, that are related to longitudinal and radial RV dysfunction.

An Adult Patient With a Tetralogy of Fallot Case

Tetralogy of Fallot (ToF) is considered the most frequent cyanotic congenital heart abnormality with a low adulthood survival rate if kept untreated. The majority of cases are symptomatic during infancy and mandate early treatment. Few instances of survival to asymptomatic middle-age patients have been reported, and they are decreasing due to early detection. We reported a case of a middle-aged man who was asymptomatic during his life and recently diagnosed with ToF. The patient underwent surgical repair with excellent outcomes. The case represents the possibility of diagnosing such cases in a relatively old patient despite medical development and advances.

CMR in Evaluating Valvular Heart Disease: Diagnosis, Severity, and Outcomes

Cardiac magnetic resonance (CMR) is a versatile imaging tool that brings much to the assessment of valvular heart disease. Although it is best known for myocardial imaging (even in valve disease), it provides excellent assessment of all 4 heart valves, with some distinct advantages, including a free choice of image planes and accurate flow and volumetric quantification. These allow the severity of each valve lesion to be characterized, in addition to optimal visualization of the surrounding outflow tracts and vessels, to deliver a comprehensive package. It can assess each valve lesion separately (in multiple valve disease) and is not affected by hemodynamic status. The accurate quantitation of regurgitant lesions and the ability to characterize myocardial changes also provides an ability to predict future clinical outcomes in asymptomatic patients. This review outlines how CMR can be used in cardiac valve disease to compliment echocardiography and enhance the patient assessment. It covers the main CMR methods used, their strengths and limitations, and the optimal way to apply them to evaluate valve disease.

Tricuspid Regurgitation in Adults after Repair of Right Ventricular Outflow Obstructive Lesions

We determined the prevalence and factors associated with tricuspid regurgitation (TR) in adults with repair of right ventricular (RV) outflow obstruction. A total of 256 patients (128 males) were studied at 25.7 ± 7.2 years after surgery, of whom 179 had repaired tetralogy of Fallot (TOF), 31 had pulmonary atresia with intact ventricular septum (PAIVS), and 46 had pulmonary stenosis (PS). The mitral and tricuspid annulus diameters, maximum right atrial (RA) area, RV end-systolic and end-diastolic areas, and tricuspid and pulmonary regurgitation were assessed using echocardiography. The prevalence of moderate-to-severe TR was 20.7%. Subgroup analysis revealed that prevalence was greater in patients with repaired TOF (20.7%) and PAIVS (35.5%) than PS patients (10.9%). As a group, severity of TR was found to be correlated with RA area (r = 0.35, p < 0.001), RV end-diastolic (r = 0.28, p < 0.001) and end-systolic (r = 0.22, p = 0.001) areas, and tricuspid valve annulus diameter (r = 0.15, p = 0.022). Moderate-to-severe TR was associated with development of cardiac arrhythmias with an odds ratio of 2.9 (95% CI 1.1 to 8.1, p = 0.031). Multivariate analysis revealed maximum RA area (β = 0.36, p = 0.016) as an independent determinant of severity of TR. Moderate-to-severe TR occurs in about one-fifth of adults with repaired TOF, PAVIS, and PS and is associated with RA dilation and risk of development of cardiac arrhythmias.

Right ventricular dilatation in patients with pulmonary regurgitation after repair of tetralogy of Fallot: How fast does it progress?

Objective

Pulmonary valve regurgitation (PR) and right ventricular (RV) dilatation are important residual findings after surgical repair of tetralogy of Fallot (TOF). We sought to describe the natural course of RV dilatation over time in patients with severe PR after TOF repair and to determine risk factors for quick progression of RV dilatation and dysfunction.

Methods

Data of 85 consecutive TOF patients with PR and RV dilatation, undergoing serial cardiovascular magnetic resonance (CMR) scans between July 2002 and December 2016 in two institutions, were retrospectively reviewed. The dataset was analyzed regarding right and left ventricular (LV) volume and function and potential risk factors of progressive RV dilatation.

Results

There was no significant increase in RV end-diastolic volumes (RVEDV_i) indexed body surface area (BSA) (median 150 [81-249] vs. 150 [82-260] mL/m²) and end-systolic volumes indexed for BSA (RVESV_i) (75 [20-186] vs. 76 [39-189] mL/m²) between the first and last CMR in the overall group. Similarly, there were no significant changes in LV volumes indexed for BSA (LVEDV_i 78 [56-137] vs. 81 [57-128] mL/m² and LV end-systolic volume index 34 [23-68] vs. 35 [18-61] mL/m2). Global function remained also unchanged for both ventricles. RVEDVi increased statistically significantly (≥20 mL/m2) in twenty patients (24%) from 154 mL/m² (87-237) to 184 mL/m² (128-260, P < 0.001). LV dimensions showed a similar trend with LVEDVi increase from 80 ml/m² (57-98) to 85 ml/m² (72-105, P = 0.002). Shorter time interval between repair and first CMR was the only risk factor predictive for progressive RV dilatation.

Conclusion

In the majority of patients with repaired TOF and severe PR, RV dilatation is unchanged during a follow-up of 3 years. RV dilatation seems to progress early after surgery and subsequently stabilize. RV dilatation significantly progresses in a subgroup of 24% of patients, with a shorter time interval since surgical repair.

Personalized Interventions: A Reality in the Next 20 Years or Pie in the Sky

There is no better representation of the need for personalization of care than the breadth and complexity of congenital heart disease. Advanced imaging modalities are now standard of care in the field, and the advancements being made to three-dimensional visualization technologies are growing as a means of pre-procedural preparation. Incorporating emerging modeling approaches, such as computational fluid dynamics, will push the limits of our ability to predict outcomes, and this information may be both obtained and utilized during a single procedure in the future. Artificial intelligence and customized devices may soon surface as realistic tools for the care of patients with congenital heart disease, as they are showing growing evidence of feasibility within other fields. This review illustrates the great strides that have been made and the persistent challenges that exist within the field of congenital interventional cardiology, a field which must continue to innovate and push the limits to achieve personalization of the interventions it provides.

Preprocedural Imaging Evaluation of Pulmonary Valve Replacement After Repair of Tetralogy of Fallot: What the Radiologist Needs to Know

Tetrallogy of Fallot (TOF) is the most frequent form of cyanotic congenital heart disease. Despite advances in surgical and medical treatment, mortality remains high. Residual dysfunction of the pulmonary valve (PV) after correction of right ventricular outflow tract obstruction is an important cause of morbidity, leading to irreversible right ventricular dysfunction, arrhythmias, heart failure and occasionally, death. The strategies for PVR have evolved over the last decades, and the timing of the intervention remains the foundation of the decision-making process. Symptoms of heart failure are unreliable indicators for optimal timing of repair. Imaging plays an essential role in the assessment of PV integrity and dysfunction. The identification of the best timing for PVR requires a multimodality approach. Transthoracic echocardiography is the most commonly used imaging modality for the initial assessment and follow-up of TOF patients, although its utility has technical limitations, especially in adults. Cardiac computed tomography and magnetic resonance imaging are now routinely used for preoperative and postoperative evaluation of these patients, and provide highly valuable information about the anatomy and pathophysiology. Imaging evidence of disease progression is now part of the major guidelines to define the best timing for reintervention. The purpose of this article is to review the pathophysiology after TOF repair, identify the main imaging anatomic and physiologic features, describe the indications for PVR and recognize the role of imaging in the assessment of these patients to define the appropriate timing of PVR.

Clinical significance of right atrial volume in patients with repaired tetralogy of Fallot

OBJECTIVES

Atrial arrhythmia and right ventricular (RV) diastolic dysfunction are associated with increased morbidity and mortality in patients with repaired tetralogy of Fallot (TOF). This study was performed to determine whether the preoperative right atrial (RA) volume can predict the development of atrial arrhythmia after pulmonary valve replacement (PVR) in patients with TOF.

METHODS

Forty-seven consecutive adult patients with repaired TOF underwent PVR from 2003 to 2018. Seventeen patients showed preoperative atrial arrhythmia and underwent the Maze procedure concomitantly. The preoperative RA volume was evaluated with computed tomography and image analysis software.

RESULTS

The median follow-up period after PVR was 6.8 years. Among 17 patients who underwent the Maze procedure, recurrent atrial arrhythmia developed in 8 patients. Among 30 patients without preoperative atrial arrhythmia, novel atrial arrhythmia developed in 2 patients. The RA volume index was a significant predictor according to the multivariate analysis (P = 0.003). The RA volume index showed a significant positive correlation with the RV end-diastolic pressure (P < 0.001).

CONCLUSIONS

The RA volume predicts the development of atrial arrhythmia after PVR in patients with repaired TOF. RA volume measurement is strongly recommended in the management of this patient population.

Changes in left and right ventricular longitudinal function after pulmonary valve replacement in patients with Tetralogy of Fallot

Timing and indication for pulmonary valve replacement (PVR) in patients with repaired Tetralogy of Fallot (rToF) and pulmonary regurgitation (PR) are uncertain. To improve understanding of pumping mechanics, we investigated atrioventricular coupling before and after surgical PVR. Cardiovascular magnetic resonance was performed in patients (n = 12) with rToF and PR > 35% before and after PVR and in healthy controls (n = 15). Atrioventricular plane displacement (AVPD), global longitudinal peak systolic strain (GLS), atrial and ventricular volumes, and caval blood flows were analyzed. Right ventricular (RV) AVPD and RV free wall GLS were lower in patients before PVR compared with controls (P < 0.0001; P < 0.01) and decreased after PVR (P < 0.0001 for both). Left ventricular AVPD was lower in patients before PVR compared with controls (P < 0.05) and decreased after PVR (P < 0.01). Left ventricular GLS did not differ between patients and controls (P > 0.05). Right atrial reservoir volume and RV stroke volume generated by AVPD correlated in controls (r = 0.93; P < 0.0001) and patients before PVR (r = 0.88; P < 0.001) but not after PVR. In conclusion, there is a clear atrioventricular coupling in patients before PVR that is lost after PVR, possibly because of loss of pericardial integrity. Impaired atrioventricular coupling complicates assessment of ventricular function after surgery using measurements of longitudinal function. Changes in atrioventricular coupling seen in patients with rToF may be energetically unfavorable, and long-term effects of surgery on atrioventricular coupling is therefore of interest. Also, AVPD and GLS cannot be used interchangeably to assess longitudinal function in rToF.NEW & NOTEWORTHY There is a clear atrioventricular coupling in patients with Tetralogy of Fallot (ToF) and pulmonary regurgitation before surgical pulmonary valve replacement (PVR) that is lost after operation, possibly because of loss of pericardial integrity. The impaired atrioventricular coupling complicates assessment of ventricular function after surgery when using measurements of longitudinal function. Left ventricular atrioventricular plane displacement (AVPD) found differences between patients and controls and changes after PVR that longitudinal strain could not detect. This indicates that AVPD and strain cannot be used interchangeably to assess longitudinal function in repaired ToF.

Whether Pulmonary Valve Replacement in Asymptomatic Patients With Moderate or Severe Regurgitation After Tetralogy of Fallot Repair Is Appropriate: A Case-Control Study

Background

Although right ventricular (RV) volume was significantly decreased in symptomatic patients with repaired tetralogy of Fallot (rTOF) after pulmonary valve replacement (PVR), RV size was still enlarged along with RV dysfunction.

Methods and Results

A prospective case‐control study was conducted in a tertiary hospital; 81 asymptomatic repaired tetralogy of Fallot patients with moderate or severe pulmonary regurgitation were enrolled. The enrolled cohort was divided into 2 groups: PVR group (n=41) and medication group (n=40). Cardiac magnetic resonance, transthoracic echocardiography, and electrocardiography were scheduled after recruitment and 6 months after PVR or recruitment. Adverse events were recorded during follow‐up. Three deaths, 1 heart transplantation, 3 PVRs, and 2 symptomatic heart failures in medication group and 1 redo PVR in the PVR group were observed during follow‐up. Compared with the medication group, the PVR group had significantly lower adverse events rate (P=0.023; odds ratio, 0.086; 95% CI, 0.010–0.716), and RV function was significantly improved (P<0.05). Binary logistic regression analysis identified preoperative RV end‐systolic volume index (10‐mL/m² increment, P=0.009; odds ratio, 0.64; 95% CI, 0.457–0.893) was an independent predictor of normalization of RV size after PVR. A preoperative RV end‐systolic volume index cut‐off value of 120 mL/m² (area under curve, 0.819; sensitivity, 90.3%; specificity, 70%) was analyzed by receiver operating characteristic curves for normalized RV size after PVR.

Conclusions

PVR in asymptomatic repaired tetralogy of Fallot patients is appropriate and effective in reducing right ventricular size and preserving right ventricular function. The recommended criterion of RV end‐systolic volume index for PVR is 120 mL/m².

Does Restrictive Lung Function Affect the Exercise Capacity in Patients with Repaired Tetralogy of Fallot?

Patients with repaired Tetralogy of Fallot (rTOF) have decreased exercise capacity (XC) and restrictive lung function (RLF). Our objective was to determine the association between RLF and impaired XC in patients with rTOF. This was a single center retrospective review of patients with rTOF who underwent a cardiopulmonary treadmill exercise testing and spirometry from 2005 to 2015. Patients with a respiratory exchange ratio ≥ 1.05 and peak heart rate > 90% of predicted value were included. Forced vital capacity (FVC) and Forced expiratory volume in 1st second of forceful expiration (FEV₁) were used to classify the lung function. Exercise parameters such as peak oxygen uptake (VO₂), % of predicted VO₂ (%VO₂), Metabolic equivalents (METS), and exercise time (ET) were compared between the two groups (i) compared patients with normal lung function (normal FEV₁, FVC, and FEV₁/FVC > 80%) (ii) RLF (FVC < 80%, normal or increased FEV₁/FVC > 80%). In our cohort (n = 151, 52% male, mean age ± SD of 22.3 ± 9.1 years), patients with RLF (n = 73) compared to those with normal lung function (n = 86) had a lower peak VO₂ (30.8 ± 8.6 vs. 36.6 ± 9.8 mL/kg/min; p < 0.001) and shorter exercise time (9:23 ± 1:78 vs. 10:23 ± 1:62 min, p < 0.001). On multivariate regression analysis, RLF was independently associated with reduced XC (VO₂%) (β-coefficient - 0.182, p < 0.02) after controlling for age and gender. RLF is common in patients with rTOF and is associated with decreased XC. The contribution of RLF to reduced XC in this population should be considered prior to therapeutic decisions.

Clinical outcomes of transcatheter versus surgical pulmonary valve replacement: a meta-analysis

Background

Transcatheter pulmonary valve replacement (TPVR) has currently been a well-established alternative operation method to surgical pulmonary valve replacement (SPVR) in patients with pulmonary valve dysfunction in the form of stenosis and/or regurgitation. We conducted a meta-analysis to evaluate the main clinical outcomes after TPVR and SPVR.

Methods

We systematically searched the references of relevant literatures from PubMed and the Cochrane Library published between January 2000 and December 2018 and followed The Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) for this study.

Results

Eleven studies with 4,364 patients were included in the study. Compared with SPVR, TPVR results in a significant decreased in-hospital mortality [odds ratio (OR): 0.18; 95% confidence interval (CI): 0.03-0.98] and mortality at the longest reported follow-up time point (OR: 0.43; 95% CI: 0.22-0.87), though 30-day mortality (OR: 0.38; 95% CI: 0.11-1.33) has no significant difference between groups. Days of hospital stay [(mean difference (MD): -4.38; 95% CI: -6.24--2.53] is shorter with TPVR than SPVR. Besides, rates of 30-day readmission (OR: 0.67; 95% CI: 0.50-0.91) and recurrent pulmonary regurgitation (OR: 0.17; 95% CI: 0.07-0.42) are lower with TPVR, whereas postprocedural infective endocarditis (IE) (OR: 4.56; 95% CI: 2.03-10.26) are higher with TPVR. SPVR carries a decreased risk of re-operation (OR: 2.19; 95% CI: 0.62-7.76) though without statistically significance.

Conclusions

In conclusion, TPVR is associated with a significantly decreased mortality, a shorter length of hospital-stay, a lower rate of 30-day readmission and recurrent pulmonary regurgitation as compared to SPVR throughout the follow-up duration, whereas SPVR results in a significantly lower rate of postprocedural IE than TPVR. In addition, SPVR carries a decreased risk of re-operation with statistically insignificance.

Late management of the aortic root after repair of tetralogy of Fallot: A European multicentre study

OBJECTIVES

We sought to determine the indications, type, and outcomes of reoperations on the aortic root after repair of tetralogy of Fallot (TOF).

METHODS

Eleven centers belonging to the European Congenital Heart Surgeons Association contributed to the data collection process. We included 36 patients who underwent surgical procedures on the aortic root, including surgery on the aortic valve and ascending aorta, between January 1975 and December 2017. Original diagnoses included TOF-pulmonary stenosis (n = 18) and TOF-pulmonary atresia (n = 18). The main indications for reoperation were aortic insufficiency (n = 19, 53%), aortic insufficiency and dilatation of the ascending aorta (n = 10, 28%), aortic root dilatation (n = 4, 11%), and ascending aorta dilatation (n = 3, 8%).

RESULTS

The median age at reoperation was 30.4 years (interquartile range 20.3-45.3 years), and mechanical aortic valve replacement was the most common procedure performed. Five patients died early after reoperation (14%), and larger ascending aorta diameters were associated with early mortality (P = .04). The median age at the last follow-up was 41.4 years (interquartile range 24.5-51.6 years). Late death occurred in five patients (5/31, 16%). Most survivors (15/26, 58%) were asymptomatic at the last clinical examination (New York Heart Association, NYHA class I). The remaining patients were NYHA class II (n = 7) and III (n = 3). The most common symptoms were fatigue (n = 5), dyspnea (n = 4), and exercise intolerance (n = 3).

CONCLUSIONS

Reoperations on the aortic root are infrequent but may become necessary late after TOF repair. The main indications for reoperation are aortic insufficiency, either isolated or associated with a dilatation of the ascending aorta. The surgical risk at reoperation was high and the presence of ascending aorta dilation is related to higher mortality.

Cardiomyopathy in Children: Classification and Diagnosis: A Scientific Statement From the American Heart Association

In this scientific statement from the American Heart Association, experts in the field of cardiomyopathy (heart muscle disease) in children address 2 issues: the most current understanding of the causes of cardiomyopathy in children and the optimal approaches to diagnosis cardiomyopathy in children. Cardiomyopathies result in some of the worst pediatric cardiology outcomes; nearly 40% of children who present with symptomatic cardiomyopathy undergo a heart transplantation or die within the first 2 years after diagnosis. The percentage of children with cardiomyopathy who underwent a heart transplantation has not declined over the past 10 years, and cardiomyopathy remains the leading cause of transplantation for children >1 year of age. Studies from the National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry have shown that causes are established in very few children with cardiomyopathy, yet genetic causes are likely to be present in most. The incidence of pediatric cardiomyopathy is ≈1 per 100 000 children. This is comparable to the incidence of such childhood cancers as lymphoma, Wilms tumor, and neuroblastoma. However, the published research and scientific conferences focused on pediatric cardiomyopathy are sparcer than for those cancers. The aim of the statement is to focus on the diagnosis and classification of cardiomyopathy. We anticipate that this report will help shape the future research priorities in this set of diseases to achieve earlier diagnosis, improved clinical outcomes, and better quality of life for these children and their families.

Surgical Pulmonary Valve Replacement Due to Failed Percutaneous Pulmonary Valve Intervention in a Patient After Correction of Fallot's Tetralogy: Surgery Remains the Standard

Patient: Male, 26

Final Diagnosis: Pulmonary valve replacement

Symptoms: No symptom

Medication: —

Clinical Procedure: —

Specialty: Surgery

4-D flow magnetic-resonance-imaging-derived energetic biomarkers are abnormal in children with repaired tetralogy of Fallot and associated with disease severity

BACKGROUND

Cardiac MRI plays a central role in monitoring children with repaired tetralogy of Fallot (TOF) for long-term complications. Current risk assessment is based on volumetric and functional parameters that measure late expression of underlying physiological changes. Emerging 4-D flow MRI techniques promise new insights.

OBJECTIVE

To assess whether 4-D flow MRI-derived measures of blood kinetic energy (1) differentiate children and young adults with TOF from controls and (2) are associated with disease severity.

MATERIALS AND METHODS

Pediatric patients post TOF repair (n=21) and controls (n=24) underwent 4-D flow MRI for assessment of time-resolved 3-D blood flow. Data analysis included 3-D segmentation of the right ventricle (RV) and pulmonary artery (PA), with calculation of peak systolic and diastolic kinetic energy (KE) maps. Total KE_RV and KE_PA were determined from the sum of the KE of all voxels within the respective time-resolved segmentations.

RESULTS

KE_PA was increased in children post TOF vs. controls across the cardiac cycle, with median 12.5 (interquartile range [IQR] 10.3) mJ/m² vs. 8.2 (4.3) mJ/m², P<0.01 in systole; and 2.3 (2.7) mJ/m² vs. 1.4 (0.9) mJ/m², P<0.01 in diastole. Diastolic KE_PA correlated with systolic KE_PA (R² 0.41, P<0.01) and with pulmonary regurgitation fraction (R² 0.65, P<0.01). Diastolic KE_RV showed similar relationships, denoting increasing KE with higher cardiac outputs and increased right heart volume loading. Diastolic KE_RV and KE_PA increased with RV end-diastolic volume in a non-linear relationship (R² 0.33, P<0.01 and R² 0.50, P<0.01 respectively), with an inflection point near 120 mL/m².

CONCLUSION

Four-dimensional flow-derived KE is abnormal in pediatric patients post TOF repair compared to controls and has a direct, non-linear relationship with traditional measures of disease progression. Future longitudinal studies are needed to evaluate utility for early outcome prediction in TOF.

EDUCATIONAL SERIES IN CONGENITAL HEART DISEASE: Tetralogy of Fallot: diagnosis to long-term follow-up

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect, affecting 3 in 10,000 live births. Surgical correction in early childhood is associated with good outcomes, but lifelong follow-up is necessary to identify the long-term sequelae that may occur. This article will cover the diagnosis of TOF in childhood, the objectives of surveillance through adulthood and the value of multi-modality imaging in identifying and guiding timely surgical and percutaneous interventions.

Long-term follow-up in adults after tetralogy of Fallot repair

Background

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease and the population of ToF repair survivors is growing rapidly. Adults with repaired ToF develop late complications. The aim of this study was to describe and analyze long-term follow-up of patients with repaired ToF.

Methods

This is a retrospective cohort study. Consecutive 83 patients with repaired ToF who did not undergo pulmonary valve replacement were included. Mean age of all patients was 30.5 ± 10.7. There were 49 (59%) male. Patients were divided into two groups according to the time since the repair (< 25 years and ≥ 25 years). The electrocardiographic (ECG), cardiopulmonary exercise testing (CPET), echocardiographic and cardiac magnetic resonance (CMR) data were reviewed retrospectively.

Results

In CPET values were not significantly different in the two groups. In CMR volumes of left and right ventricles were not significantly different in the two groups. There were no differences between the groups in ventricular ejection fraction, mass of ventricles, or pulmonary regurgitation fraction. Among all the patients, ejection fraction and left and right ventricle mass, indexed pulmonary regurgitation volume measured by CMR did not correlate with the time since repair. In ECG among all the patients, ejection fraction of the RV, measured in CMR, negatively correlated with QRS duration (r = − 0.43; p < 0.001). There was a positive correlation between QRS duration and end diastolic volume of the RV (r = 0.30; p < 0.02), indexed end diastolic volume of the RV (r = 0.29; p = 0.04), RV mass (r = 0.36; p < 0.001) and left ventricle mass (r = 0.26; p = 0.04).

Conclusion

Long-term survival and clinical condition after surgical correction of ToF in infancy is generally good and the late functional status in ToF – operated patients could be excellent up to 25 years after the repair. QRS duration could be an utility and easy factor to assessment of right ventricular function.

Trial registration

The study protocol was approved by the local Ethics Committee. Each participant provided informed consent to participate in the study (license number 122.6120.88.2016 from 28.04.2016).