Prophylactic Pulmonary Artery Banding in Pediatric Dilated Cardiomyopathy: An Additional Therapeutic Option.

Dilated cardiomyopathy (DCM) is the most common childhood cardiomyopathy and is associated with considerable early mortality. Heart transplantation is often the only viable life-saving option. Pulmonary artery banding (PAB) has been recently proposed as a bridge or alternative to transplantation for DCM. In our cohort, PAB was selectively addressed to heritable DCM or DCM with congenital left ventricle aneurysm (CLVA). This study aimed to describe the clinical evolution and left ventricle reverse remodeling (LVRR) over time (6 months and 1 year after surgery). Ten patients with severe DCM received PAB between 2016 and 2021 and underwent clinical and postoperative echocardiography follow-ups. The median age at PAB was <1 year. The in-hospital mortality was zero. Two patients died two months after PAB of end-stage heart failure. The modified Ross class was improved in the eight survivors with DCM and remained stable in the two patients with CLVA. We observed a positive LVRR (LV end-diastolic diameter Z-score: 8.4 ± 3.7 vs. 2.8 ± 3; p < 0.05; LV ejection fraction: 23.8 ± 5.8 to 44.5 ± 13.1 (p < 0.05)). PAB might be useful as part of the armamentarium available in infants and toddlers with severe DCM not sufficiently responding to medical treatment with limited probability of spontaneous recovery.

Ross procedure or complex aortic valve repair using pericardium in children: A real dilemma.

OBJECTIVE: Difficult to repair aortic valve lesions, requiring the use of a valve substitute, remain controversial in the face of the Ross procedure, despite undeniable technical advances. This study was undertaken to compare midterm outcomes of children treated using the Ross procedure or aortic valvuloplasty for complex aortic valve lesions. METHODS: Between January 2006 and December 2017, 126 patients aged younger than 18 years were treated for complex aortic stenosis and/or aortic insufficiency and were included in this retrospective study. Only aortic valve lesions requiring repair with an autologous or heterologous pericardial patch were considered complex lesions. Propensity score framework analyses were used to compare outcomes of the Ross and aortic valvuloplasty groups while controlling for confounders. RESULTS: Among the 126 patients with complex aortic valve lesions, propensity score matching selected 34 unique pairs of patients with similar characteristics. Survival (aortic valvuloplasty, 94.1%; Ross, 91%; P = .89), freedom from overall reintervention (aortic valvuloplasty, 50.1%; Ross, 69%; P = .32), and freedom from infective endocarditis at 8 years (aortic valvuloplasty, 100%; Ross, 85.9%; P = .21) were similar. However, freedom from reintervention in the left ventricular outflow tract at 8 years was lower after aortic valvuloplasty than after the Ross procedure (50.1% vs 100%, respectively; P = .001). CONCLUSIONS: Aortic valvuloplasty and the Ross procedure yielded similar 8-year outcomes regarding death, reoperation, and infective endocarditis although aortic valvuloplasty tended to be associated with fewer cases of infective endocarditis. Aortic valvuloplasty using a pericardial patch can be chosen as a first-line strategy for treating complex aortic valve lesions and might offer the possibility of a later Ross procedure.

Cardiovascular events in perimembranous ventricular septal defect with left ventricular volume overload: a French prospective cohort study (FRANCISCO).

The long-term prospective multi-centre nationwide (French) observational study FRANCISCO will provide new information on perimembranous ventricular septal defect with left ventricular overload but no pulmonary hypertension in children older than 1 year. Outcomes will be compared according to treatment strategy (watchful waiting, surgical closure, or percutaneous closure) and anatomic features of the defect. The results are expected to provide additional guidance about the optimal treatment of this specific population, which is unclear at present. BACKGROUND: The management of paediatric isolated perimembranous ventricular septal defect (pmVSD) with left ventricle (LV) volume overload but no pulmonary arterial hypertension (PAH) remains controversial. Three therapeutic approaches are considered: watchful waiting, surgical closure, and percutaneous closure. We aim to investigate the long-term outcomes of these patients according to anatomic pmVSD characteristics and treatment strategy. METHODS: The Filiale de Cardiologie Pediatrique et Congénitale (FCPC) designed the FRANCISCO registry, a long-term prospective nationwide multi-centre observational cohort study sponsored by the French Society of Cardiology, which enrolled, over 2 years (2018­2020), patients older than 1 year who had isolated pmVSD with LV volume overload. Prevalent complications related to pmVSD at baseline were exclusion criteria. Clinical, echocardiographic, and functional data will be collected at inclusion then after 1, 5, and 10 years. A core lab will analyse all baseline echocardiographic data to depict anatomical pmVSD features. The primary outcome is the 5-year incidence of cardiovascular events (infective endocarditis, sub-aortic stenosis, aortic regurgitation, right ventricular outflow tract stenosis, tricuspid regurgitation, PAH, arrhythmia, stroke, haemolysis, heart failure, or death from a cardiovascular event). We plan to enrol 200 patients, given the 10% estimated 5-year incidence of cardiovascular events with a 95% confidence interval of ±5%. Associations linking anatomical pmVSD features and treatment strategy to the incidence of complications will be assessed. CONCLUSIONS: The FRANSCICO study will provide the long-term incidence of complications in patients older than 1 year with pmVSD and LV volume overload. The results are expected to improve guidance for treatment decisions.

Continuous positive airway pressure improves work of breathing in pediatric chronic heart failure.

BACKGROUND: Sleep disordered breathing (SDB) is common in adults with chronic heart failure (CHF), but its prevalence in children remains unclear. Continuous positive airway pressure (CPAP) is the treatment of SDB but deleterious hemodynamic effects have been reported. METHODS: We prospectively analyzed SDB in children with CHF and the effect of CPAP on work of breathing (WOB) and cardiac index (CI). Children aged 6 months to 18 years old with CHF due to: 1) dilated cardiomyopathy (DM) with an ejection fraction < 45%, 2) functional single ventricle (SV) or 3) aortic or mitral valve disease awaiting surgery (VD) were eligible for the study. A polysomnography (PSG), measurement of WOB and CI during spontaneous breathing (SB) and CPAP (6, 8 and 10 cmH2O) were performed. RESULTS: Thirty patients with mean age of 6.4 ± 5 years were included (16 DM 16, 10 SV, 4 LV). Twenty (73%) patients had a normal sleep efficiency. Median apnoeas hypopnea index (IAH) was within normal range at 1.6 events/h (0, 14) events/hour. Only one patient had central sleep apnoeas, none had Cheyne-Stokes respiration, and 3 patients had an obstructive AHI between 5 and 10 events/hour. Optimal CPAP level decreased WOB (p = 0.05) and respiratory rate (p = 0.01). CONCLUSIONS: Severe SDB was uncommon in children with CHF. However, CPAP may be beneficial by decreasing WOB and respiratory rate without deleterious effects on CI.

Geleophysic and acromicric dysplasias: natural history, genotype-phenotype correlations, and management guidelines from 38 cases.

PURPOSE: Geleophysic dysplasia (GD) and acromicric dysplasia (AD) are characterized by short stature, short extremities, and progressive joint limitation. In GD, cardiorespiratory involvement can result in poor prognosis. Dominant variants in the FBN1 and LTBP3 genes are responsible for AD or GD, whereas recessive variants in the ADAMTSL2 gene are responsible for GD only. The aim of this study was to define the natural history of these disorders and to establish genotype-phenotype correlations. METHODS: This monocentric retrospective study was conducted between January 2008 and December 2018 in a pediatric tertiary care center and included patients with AD or GD with identified variants (FBN1, LTBP3, or ADAMTSL2). RESULTS: Twenty-two patients with GD (12 ADAMTSL2, 8 FBN1, 2 LTBP3) and 16 patients with AD (15 FBN1, 1 LTBP3) were included. Early death occurred in eight GD and one AD. Among GD patients, 68% presented with heart valve disease and 25% developed upper airway obstruction. No AD patient developed life-threatening cardiorespiratory issues. A greater proportion of patients with either a FBN1 cysteine variant or ADAMTSL2 variants had a poor outcome. CONCLUSION: GD and AD are progressive multisystemic disorders with life-threatening complications associated with specific genotype. A careful multidisciplinary follow-up is needed.

Predictors of low exercise cardiac output in patients with severe pulmonic regurgitation.

BACKGROUND AND OBJECTIVES: Chronic pulmonic regurgitation (PR) following repair of congenital heart disease (CHD) impairs right ventricular function that impacts peak exercise cardiac index (pCI). We aimed to estimate in a non-invasive way pCI and peak oxygen consumption (pVO2) and to evaluate predictors of low pCI in patients with significant residual pulmonic regurgitation after CHD repair. METHOD: We included 82 patients (median age 19 years (range 10-54 years)) with residual pulmonic regurgitation fraction >40%. All underwent cardiac MRI and cardiopulmonary testing with measurement of pCI by thoracic impedancemetry. Low pCI was defined <7 L/min/m2. RESULTS: Low pCI was found in 18/82 patients. Peak indexed stroke volume (pSVi) tended to compensate chronotropic insufficiency only in patients with normal pCI (r=-0.31, p=0.01). Below 20 years of age, only 5/45 patients had low pCI but near-normal (≥6.5 L/min/m2). pVO2 (mL/kg/min) was correlated with pCI (r=0.58, p=0.0002) only in patients aged >20 years. Left ventricular stroke volume in MRI correlated with pSVi only in the group of patients with low pCI (r=0.54, p=0.02). No MRI measurements predicted low pCI. In multivariable analysis, only age predicted a low pCI (OR=1.082, 95% CI 1.035 to 1.131, p=0.001) with continuous increase of risk with age. CONCLUSIONS: In patients with severe PR, pVO2 is a partial reflection of pCI. Risk of low pCI increases with age. No resting MRI measurement predicts low haemodynamic response to exercise. Probably more suitable to detect ventricular dysfunction, pCI measurement could be an additional parameter to take into account when considering pulmonic valve replacement.

Aortic angle is associated with neo-aortic root dilatation and regurgitation following arterial switch operation.

INTRODUCTION: Neo-aortic root dilatation and regurgitation are common progressive long-term complications of the arterial switch operation (ASO) for transposition of the great arteries (TGA) with increasing clinical burden. While several risk factors have been identified, most are constitutional. The acute aortic angle commonly seen after ASO might alter aortic dynamics and facilitate progression of the neo-aortic root dilatation and aortic regurgitation, but insufficient data is available. We intend to assess the effect of the aortic angle in the extent of neo-aortic root dilatation and presence of regurgitation. METHODS: Retrospective analysis of TGA patients undergoing CMR after ASO at a single tertiary centre from November 2010 to July 2017. RESULTS: 180 patients were analysed, 157 of which having adequate imaging of the aortic arch and root. Neo-aortic root Z score was normally distributed with 73% of patients having a Z score > 2. The aortic angle had a significant (p < 0,001) inverse relationship with the neo-aortic root Z score both in univariate and multivariate linear regression. Other significant associations were male gender and the concomitant presence of a VSD or a dysplastic neo-aortic valve. The presence of neo-aortic regurgitation was also inversely correlated with the aortic angle. The presence of a bicuspid neo-aortic valve was another significant association, further correlating with the more severe forms. CONCLUSIONS: Acute aortic angles associate more extensive neo-aortic root dilatation and higher incidence of regurgitation. We believe a surgical technique promoting less acute aortic angles has potential for ameliorating the long-term outcomes of TGA.

Long-term results of the modified Konno procedure in high-risk children with obstructive hypertrophic cardiomyopathy.

OBJECTIVE: Transaortic septal myectomy is the gold standard surgery in obstructive hypertrophic cardiomyopathy, but it is not optimal for children aged less than 5 years and with right ventricular outflow tract obstruction. We evaluated outcomes with the modified Konno procedure in children with severe forms of obstructive hypertrophic cardiomyopathy. METHODS: A total of 79 consecutive children who underwent the modified Konno procedure in our center between 1991 and 2016 were included. RESULTS: Clinical features included age less than 5 years (38%), maximal septal thickness 25 mm or more (32%), extension to the left ventricular apex (29%), and right ventricular outflow tract obstruction (28%). In total, 25% of patients had Noonan syndrome. Five children (6%) aged less than 15 months with Noonan syndrome and biventricular obstruction died in the hospital. Mean follow-up was 6 ± 5.7 years. Survival without death and heart transplantation was 82% at 20 years. Atrioventricular block occurred in 9 patients (11%) and was associated with right ventricular outflow tract obstruction and surgery before 2010. Death, resuscitated sudden cardiac death, and appropriate implantable defibrillator shock were associated with maximal septal thickness before surgery (adjusted odds ratio, 1.20; 95% confidence interval, 1.07-1.35; P = .002) and need for an associated procedure (adjusted odds ratio, 8.84; 95% confidence interval, 2.01-38.93; P = .004). There was no case of recurrent obstruction. Reoperation was required in 4 patients (5%) for other reasons. CONCLUSIONS: The modified Konno procedure provided durable obstruction relief and good long-term survival in children with severe forms of obstructive hypertrophic cardiomyopathy. Children with Noonan syndrome undergoing surgery early in life were at higher risk of early mortality.

Myocardial inflammation detected by cardiac MRI in Arrhythmogenic right ventricular cardiomyopathy: A paediatric case series.

INTRODUCTION: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease with an elusive association with myocardial inflammation. A myocarditis phenotype has been well established without systematic evidence of a viral trigger. We intend to study the relationship between myocardial inflammation detected by Cardiac magnetic resonance (CMR) and ARVC in a paediatric population. METHODS: Retrospective case series of all patients <18 years admitted to two CMR units for clinical suspicion of myocarditis from March 2012 to June 2017 who had genetic testing for inherited cardiomyopathies including analysis for known ARVC genes. RESULTS: Six patients were identified experiencing myocarditis-like episodes with chest pain and troponin elevation. All had CMR evidence of active myocardial inflammation often affecting the left ventricle without identification of an infectious trigger. These episodes were likely exercise-induced in 50% of our patients and were multiple in all but one. CONCLUSION: We provide evidence that ARVC can present as recurrent myocarditis-like episodes with CMR evidence of myocardial inflammation despite absent infectious trigger in children. We believe they represent an active hot phase of the disease and may lead to disease progression.

Safety and Feasibility of the Transcatheter Approach to Create a Reverse Potts Shunt in Children With Idiopathic Pulmonary Arterial Hypertension.

BACKGROUND: The reversed Potts shunt improves right ventricular (RV) function in patients with suprasystemic pulmonary arterial hypertension (PAH). The proximity of the left pulmonary artery (LPA) to the descending aorta (DAo) permits the creation of a transcatheter connection. We sought to assess the safety, feasibility, and hemodynamic efficacy of the transcatheter Potts shunt (TPS) in children. METHODS: The TPS procedure was performed using radiofrequency energy for vessel perforation and deployment of a covered stent to connect the DAo and LPA. Procedural details and clinical follow-up data were collected prospectively. RESULTS: A TPS was successfully created in 6 children (mean age, 11.0 ± 4.2 years) with drug-refractory suprasystemic PAH and deteriorating RV function. All patients exhibited nearly complete equalization of aortic and pulmonary pressures and improvement in RV contractility within days after TPS placement. Two patients with pre-existing severe biventricular dysfunction and pericardial effusion experienced acute low-output states immediately after shunt creation because of sudden reductions in left ventricular (LV) preload, resulting in cardiac arrest, irreversible brain damage, and death. Stent dislodgement and embolization into the iliac artery occurred in 1 patient. The stent was successfully secured and followed by placement of a second stent at the target location. The procedure was uncomplicated in 4 patients, who remain alive after a mean follow-up of 10 ± 2.6 months. Intravenous vasodilator therapy was weaned uneventfully after TPS in 3 patients. CONCLUSIONS: TPS creation in children is feasible and results in hemodynamic improvement. Further insights into high-risk markers, such as reduced preprocedural LV function and preload reserves, are important for guiding patient selection.

Radiation dose reduction in paediatric coronary computed tomography: assessment of effective dose and image quality.

OBJECTIVES: To assess the impact of different protocols on radiation dose and image quality for paediatric coronary computed tomography (cCT). MATERIALS AND METHODS: From January-2012 to June-2014, 140 children who underwent cCT on a 64-slice scanner were included. Two consecutive changes in imaging protocols were performed: 1) the use of adaptive statistical iterative reconstruction (ASIR); 2) the optimization of acquisition parameters. Effective dose (ED) was calculated by conversion of the dose-length product. Image quality was assessed as excellent, good or with significant artefacts. RESULTS: Patients were divided in three age groups: 0-4, 5-7 and 8-18 years. The use of ASIR combined to the adjustment of scan settings allowed a reduction in the median ED of 58 %, 82 % and 85 % in 0-4, 5-7 and 8-18 years group, respectively (7.3 ± 1.4 vs 3.1 ± 0.7 mSv, 5.5 ± 1.6 vs 1 ± 1.9 mSv and 5.3 ± 5.0 vs 0.8 ± 2.0 mSv, all p < 0,05). Prospective protocol was used in 51 % of children. The reduction in radiation dose was not associated with reduction in diagnostic image quality as assessed by the frequency of coronary segments with excellent or good image quality (88 %). CONCLUSIONS: cCT can be obtained at very low radiation doses in children using ASIR, and prospective acquisition with optimized imaging parameters. KEY POINTS: • Using ASIR allows 25 % to 41 % reduction in the ED. • Prospective protocol is used up to 51 % of children after premedication. • Low dose is possible using ASIR and optimized prospective paediatric cCT.

Mechanisms of coronary complications after the arterial switch for transposition of the great arteries.

BACKGROUND: The arterial switch operation (ASO) for transposition of the great arteries requires transfer of the coronary arteries from the aorta to the proximal pulmonary artery (neoaorta). This is complicated by variable coronary anatomy before transfer. In 8% to 10% of cases, there is evidence of late coronary stenosis and/or occlusion, often with catastrophic clinical consequences. The mechanism of such complications has not been well studied. METHODS AND RESULTS: We analyzed 190 consecutive high-resolution computed tomographic scans from the ASO procedure (patients aged 5-16 years) and found 17 patients with significant (>30% up to occlusion) coronary lesions (8.9%); all were later confirmed by conventional angiography. The left main coronary artery was abnormal in 9 patients (ostium in all), the left anterior descending artery in 3, the circumflex in 2, and the right coronary artery in 3 patients. Using multiplanar and 3-dimensional reconstructions of the coronary arteries, aorta, and pulmonary artery, we identified the commonest mechanisms of coronary abnormalities. For the left main and left anterior descending artery, anterior positioning of the transferred left coronary artery (between 12 and 1 o'clock on the neoaorta) appeared to predispose to a tangential course of the proximal left coronary artery promoting stenosis. All circumflex lesions occurred in Yacoub type D coronaries where a long initially retroaortic artery was stretched by its new positioning behind an enlarged neoaorta. Right coronary artery lesions occurred only in cases in which the reimplantation site was very high above the right coronary sinus with potential compression from the main pulmonary artery bifurcation immediately above. CONCLUSIONS: Thus detailed multiplanar computed tomographic scanning can elucidate the mechanisms of late coronary complications after the ASO. Understanding these aspects could help to improve surgical technique to minimize the risk of late coronary obstructions.