Diagnosis of Menke-Hennekam syndrome by prenatal whole exome sequencing and review of prenatal signs.

INTRODUCTION: CREBBP truncating mutations and deletions are responsible for the well-known Rubinstein-Taybi syndrome. Recently, a new, distinct CREBBP-linked syndrome has been described: missense mutations located at the 3' end of exon 30 and the 5' portion of exon 31 induce Menke-Hennekam syndrome. Patients with this syndrome present a recognizable facial dysmorphism, intellectual disability of variable severity, microcephaly, short stature, autism, epilepsy, visual and hearing impairments, feeding problems, upper airway infections, scoliosis, and/or kyphosis. To date, all diagnoses were made postnatally. METHOD AND CASE REPORT: Trio-whole exome sequencing (WES) was performed in a fetus showing increased nuchal translucency persistence and aorta abnormalities at 28 weeks of gestation (WG). RESULTS: WES revealed a CREBBP de novo missense mutation (c.5602C>T; p.Arg1868Trp) in exon 31, previously reported as the cause of Menke-Hennekam syndrome. Termination of pregnancy was performed at 32 WG. We further reviewed the prenatal signs of Menke-Hennekam syndrome already reported. Among the 35 patients reported and diagnosed postnatally up to this day, 15 presented recognizable prenatal signs, the most frequent being intra-uterine growth retardation, brain, and cardiovascular anomalies. CONCLUSION: Menke-Hennekam is a rare syndrome with unspecific, heterogeneous, and inconstant prenatal symptoms occurring most frequently with the c.5602C>T, p.(Arg1868Trp) mutation. Therefore, the prenatal diagnosis of Menke-Hennekam syndrome is only possible by molecular investigation. Moreover, this case report and review reinforce the importance of performing prenatal WES when unspecific signs are present on imaging.

[Fetal aortic valvuloplasty in critical aortic stenosis: indication, technique and postnatal outcomes]. / Valvuloplastie aortique fœtale pour sténose aortique critique : indications, technique et devenir postnatal.

Aortic stenosis is a complex heart disease that involves the aortic valve and the left ventricle. Impairment of the left ventricle, abnormalities in its size, systolic and diastolic function determine the postnatal outcomes in the same way as the aortic valve. In the most severe forms, the left ventricle cannot provide systemic circulation at birth and the physiology is that of hypoplastic left heart syndrome. Fetal aortic valvuloplasty has been developed in the 90s to prevent in utero progression of aortic stenosis to hypoplastic left heart syndrome. In the present article, the most recently reported data about indications, procedure details and postnatal outcomes were reviewed.

Management and Outcomes of Neonatal Arteriovenous Brain Malformations with Cardiac Failure: A 17 Years' Experience in a Tertiary Referral Center.

OBJECTIVES: To assess the management and outcomes of neonatal arteriovenous brain malformations (mostly vein of Galen malformations) complicated by cardiac failure in the era of prenatal diagnosis and endovascular treatment in a tertiary referral center. STUDY DESIGN: This observational study included 77 living newborn infants with arteriovenous brain malformations with cardiac failure, admitted to our referral center from 2001 to 2017. All infants underwent cardiovascular evaluation including echocardiogram and brain magnetic resonance imaging. Long-term survivors had standard neurocognitive assessments. RESULTS: Infants were admitted to the neonatal intensive care unit at a median of 5 days of age (including 18 inborn patients since 2009). Sixty transarterial shunt embolizations were performed in 46 patients during their first month (at a median age of 7.5 days) or postponed beyond the first month in another 10 long-term survivors. Embolization was not performed in 21 infants, including 19 nonsurvivors with severe brain injury, uncontrolled cardiac failure, or multiple organ failure. Cardiac failure requiring vasopressor infusion occurred in 48 patients (64%) during the hospitalization. Infants who survived the first month underwent a median of 3 embolization sessions. Among the 51 survivors, 21 had a good outcome and 19 had a poor outcome at follow-up (median age, 5.3 years); 11 children were lost to follow-up. CONCLUSIONS: In the era of multidisciplinary prenatal diagnosis, using a standardized care protocol, 47% of liveborn infants with an arteriovenous shunt malformation with cardiac failure experienced a favorable outcome.

Successful in utero transesophageal pacing for severe drug-resistant tachyarrhythmia.

Sustained fetal tachyarrhythmia can evolve into a life-threatening condition in 40% of cases when hydrops develops, with a 27% risk of perinatal death. Several antiarrhythmic drugs can be given solely or in combination to the mother to achieve therapeutic transplacental concentrations. Therapeutic failure could lead to progressive cardiac insufficiency and restrict therapeutic options to either elective delivery or direct fetal administration of antiarrhythmic drugs, which may increase the risk of death. We report for the first time successful fetal transesophageal pacing to treat a hydropic fetus with drug-resistant tachyarrhythmia.

Discordances Between Pre-Natal and Post-Natal Diagnoses of Congenital Heart Diseases and Impact on Care Strategies.

BACKGROUND: Pre-natal diagnosis of congenital heart disease (CHD) allows anticipation of urgent neonatal treatment and provides adequate information to the parents on cardiac outcomes. OBJECTIVES: This study sought to analyze the discordances between expert fetal cardiac diagnosis and final diagnosis of CHD and their impact on neonatal and long-term care strategies. METHODS: We included 1,258 neonates with a pre-natally diagnosed CHD and 189 fetopsies following termination of pregnancy at our tertiary center over a 10-year period. Pre-natal echocardiographic and final diagnoses were compared. RESULTS: For live births, we identified 368 (29.3%) discordances between pre- and post-natal diagnoses. The pre-natal diagnosis was different from the post-natal diagnosis in 36 cases (2.9%) and partially different with a major impact on neonatal treatment of the CHD in 97 cases (7.7%). In 235 cases (18.7%), the diagnosis was partially different with no impact on neonatal planned treatment. The discordances had a negative impact on late care strategy in 62 cases (4.9%): more complex CHD that was unsuitable for biventricular repair, leading to unplanned compassionate care, additional surgery or increase of the complexity level of the Aristotle score. A positive impact was found in 31 cases (2.5%): less complex CHD that allowed biventricular repair, fewer surgical procedures, or decrease of the complexity of the Aristotle score. For 275 patients (21.9%), there was no impact on late care strategy. Of the 872 terminations of pregnancy and intrauterine fetal deaths, 189 fetopsies were available: 16 (8.5%) different diagnoses, 27 (14.3%) major differences, and 60 (31.7%) minor differences. CONCLUSIONS: Correcting fetal cardiac diagnosis after birth can lead to significant changes in neonatal (10.6%) and late (7.4%) care strategies. Tools should be developed to try to improve the accuracy of pre-natal diagnosis of CHD. Clinicians should be cautious when predicting required treatment and outcomes during pre-natal counseling.

Critical Congenital Heart Diseases in Preterm Neonates: Is Early Cardiac Surgery Quite Reasonable?

Prematurity is a recognized risk factor for morbidity and mortality following cardiac surgery. Postoperative and long-term outcomes after cardiac surgery performed in the preterm period are poorly described. The aim of this study was to analyze a population of preterm neonates operated on for critical congenital heart disease (CHD) before 37 weeks of gestational age (wGA) with special attention given to early and late mortality and morbidity. Between 2000 and 2013, 28 preterm neonates (median gestational age (GA) 34.3 weeks) underwent cardiopulmonary bypass (CPB) surgery for critical CHD before 37 wGA; records were retrospectively reviewed. All patients except three with single ventricle physiology had a single-stage anatomic repair. Overall mortality was 43 % (95 % CI 25-62). Risk factors for death were birth weight (p = 0.032) and weight at surgery (p = 0.037), independently of GA, preoperative status, CPB and aortic clamp time. Seven patients, including those with univentricular hearts, died during the postoperative period, and five in the first year after surgery. Median follow-up was 5.9 years (range 1 month-12.8 years). Kaplan-Meier survival rate was 75 % (95 % CI 59-91) at 1 month, and 57 % (95 % CI 39-75) at 1 and 5 years. Eight patients required reoperations after a delay of 2.8 ± 1.3 months; eight had bronchopulmonary dysplasia. At the end of follow-up, nine patients were asymptomatic. One-stage biventricular repair for critical CHD on preterm neonates was feasible. Mortality remained high but acceptable, mainly confined to the first postoperative year and related to small weight. Despite reoperations, long-term clinical status was good in most survivors. Further long-term prospective investigations are necessary to evaluate neurodevelopmental outcomes.

Repeat mitral valve repair for haemolysis in children.

BACKGROUND: Severe haemolysis is a rare complication after mitral valve repair in congenital heart disease. AIM: We describe four children with severe mitral regurgitation who underwent valve repair and subsequently developed profound haemolytic anaemia. METHODS: Clinical, echocardiographic and surgical data were collected retrospectively from a surgical centre in France during a 5-year period. RESULTS: Two patients had atrioventricular septal defects, one patient had congenital mitral dysplasia and one had anomalous left coronary artery from the pulmonary artery with mitral regurgitation. Haemolysis was diagnosed 20 to 75 days after surgery, as a result of clinical and biological examination; it was severe, and blood transfusion support was necessary in all cases. Haemolysis was always associated with eccentric mitral regurgitation with a variable degree of severity (from low to severe). After exclusion of other haemolysis aetiology, redo mitral repair surgery was performed successfully in all cases. The haemolysis was considered to be mechanical in origin, caused by regurgitation of blood through the residual mitral regurgitation and stitches. CONCLUSION: Severe haemolysis is a rare complication that can occur after mitral valve repair in congenital heart disease. All patients underwent successful redo repair and had resolution of haemolysis after surgery. Even if redo surgery is required, iterative mitral repair is possible.

Case of a healthy infant born following antenatal enterovirus myocarditis and hydrops.

Fetal hydrops and myocarditis were diagnosed in a woman at 32 weeks of gestation (WG). Transplacental enterovirus infection was suspected because all other causes of myocarditis and hydrops were excluded, it was during an endemic period, and there was a setting of maternal infection (fever a few days before). We opted for in utero treatment because of the risk of resuscitating a neonate with myocarditis and hydrops. We administered dexamethasone 12mg twice for pulmonary maturation and presumed it would partially improve the myocarditis. Fetal arrhythmia was noted at 35 WG and we decided to deliver the infant as postnatal treatment of the heart disorder would be more effective. RT-PCR (ARGENE(®)) showed that the neonate's throat and anal tissues and cord blood sampled on the day of birth contained enterovirus ribonucleic acid and coxsackievirus B5, as did the mother's anal sample. Laboratory tests, heart MRI and probably brain MRI indicated neonatal enterovirus infection. Findings were normal at two-year follow-up.

A standardized repair-oriented strategy for mitral insufficiency in infants and children: midterm functional outcomes and predictors of adverse events.

OBJECTIVE: Surgical management of mitral regurgitation (MR) in children remains a challenge because of the heterogeneity of the anatomy, growth potential, and necessity to avoid valve replacement. Our objective was to assess the functional outcomes and prognostic factors of a standardized strategy of mitral valve (MV) repair for children with MR. METHODS: Consecutive patients aged <18 years who had undergone surgery for severe MR from 2001 to 2012 were studied retrospectively. The standardized repair strategy mainly included leaflet debridement, annuloplasty, and leaflet augmentation. Multivariable risk analyses for recurrent MR (grade>II), transmitral mean echocardiographic gradient>5 mm Hg, MV reoperation, replacement, and mortality were performed. RESULTS: A total of 106 patients were included (median age, 5.1 years; range, 11 days to 18 years). The mean follow-up period was 3.9±3.2 years (range, 2 months to 11 years). The proportion of congenital and left heart obstruction-related (left ventricular outflow tract obstruction) etiology was 49% (n=52) and 11% (n=12), respectively. MV repair was performed primarily in 97% of the patients. The mortality, reoperation, replacement, and MR rate at the last follow-up visit was 4.5% (n=5), 23% (n=24), 5.5% (n=6), and 17% (n=18), respectively. Actuarial survival was 93%±2% at 10 years. Freedom from MV replacement was 95%±2% and 86%±7% at 5 and 15 years, respectively. Native valve preservation was obtained in 85% of the infants and 94% beyond infancy. Independent predictors of recurrent MR, MV reoperation, and replacement included left ventricular outflow tract obstruction etiology (hazard ratio, 45; P=.004), associated preoperative mitral stenosis (hazard ratio, 21; P=.03), and young age (hazard ratio, 1.2; P=.04). CONCLUSIONS: A standardized and reproducible MV repair strategy can achieve satisfactory functional results in infants and children with severe MR, allowing native valve preservation. The left ventricular outflow tract obstruction-related etiology was the main independent predictor of recurrent MR, MV reoperation, and MV replacement.

Reoperations for left atrioventricular valve dysfunction after repair of atrioventricular septal defect.

OBJECTIVES: Postoperative left atrioventricular valve (LAVV) dysfunction is known to be the principal risk factor influencing outcome after repair of all types of atrioventricular septal defect (AVSD). The purpose of the present study was to identify the risk factors for reoperation and to assess the outcomes after reoperation for LAVV dysfunction. METHODS: Records of 412 patients who underwent anatomical repair for different types of AVSD from January 2000 to July 2012 were reviewed. The study group (n = 60) included 13 additional patients for whom repair ± LAVV reoperation was performed in a primary institution. Outcomes, independent risk factors, reoperation and death were analysed. RESULTS: There were 7 early, (1.7%) and 1 late death. Forty-seven (11.4%) required 64 reoperations for LAVV dysfunction. The median delay for the first LAVV reoperation was 3.5 months (range: 5 days to 10.0 years). Unbalanced ventricles with small left ventricle [odds ratio (OR) = 4.06, 95% confidence interval (CI): 1.58-10.44, P = 0.004], double-orifice LAVV (OR = 5.04, 95% CI: 1.39-18.27, P = 0.014), prior palliative surgery (OR = 3.5, 95% CI: 1.14-10.8, P = 0.029) and discharge echocardiography documenting LAVV regurgitation grade >2 (OR = 21.96, 95% CI: 8.91-54.09, P < 0.001) were found to be independent risk factors for LAVV reoperation. Twelve-year survival and freedom from LAVV reoperation rates were, respectively, 96.1% (95% CI: 94.1-98.1) and 85.8% (95% CI: 81.3-90.3). Survival was significantly worse in patients who underwent LAVV reoperation (P < 0.001) and in those who underwent valve replacement vs valve repair (P = 0.020). CONCLUSION: After AVSD repair, LAVV dysfunction appears to be the principal factor that influences outcome. It can usually be managed by repair. Need for multiple reoperations is not uncommon. Long-term outcome in patients with repaired LAVV is favourable.

Surface-length index: a novel index for rapid detection of right ventricles with abnormal ejection fraction using cardiac MRI.

OBJECTIVE: To validate a new index, the surface-length index (SLI) based on area change in a short-axis view and length reduction in the horizontal long-axis view, which is used to quickly (<1 min) detect right ventricles with an abnormal ejection fraction (EF) during a cardiac MRI examination. SLI can be used to avoid a complete delineation of the endocardial contours of normal right ventricles. METHODS: Sixty patients (group A) were retrospectively included to calibrate the SLI formula by optimisation of the area under the ROC curves and SLI thresholds were chosen to obtain 100 % sensitivity. Another 340 patients (group B) were prospectively recruited to test SLI's capacity to detect right ventricles (RVs) with an abnormal EF (<0.5). RESULTS: The appropriate threshold to obtain 100 % sensitivity in group A was 0.58. In group B, with the 0.58 threshold, SLI yielded a sensitivity of 100 % and specificity of 51 %. SLI would have saved 35 % of the RV studies in our population, without inducing any diagnostic error. SLI and EF correlation was good (r (2) = 0.64). CONCLUSION: SLI combines two simple RV measures, and brings significant improvement in post-processing efficiency by preselecting RVs that require a complete study. KEY POINTS: • Assessment of right ventricle ejection fraction (RVEF) with cine-MRI is time consuming. • Therefore, RVEF is not always assessed during cardiac MRI. • Surface-length index (SLI) allows rapid detection of abnormal RVEF during cardiac MRI. • SLI saves one third of the operator time. • Every cardiac MRI could include RVEF assessment by means of SLI.

Arterial switch for transposition with left outflow tract obstruction: outcomes and risk analysis.

BACKGROUND: The long-term results and indications of the arterial switch operation (ASO) for transposition of the great arteries (TGA) and anatomic left ventricular outflow tract obstruction (LVOTO) remain undetermined. The aims of this study were to determine long-term outcomes and prognostic factors in this specific population. METHODS: Between 1986 and 2011, 55 patients with TGA and anatomic LVOTO underwent ASO. Anatomic LVOTO was defined as an echocardiographic peak LVOT gradient exceeding 20 mm Hg associated with an anatomic narrowing. Forty-three patients had a ventricular septal defect. Median follow-up was 7.9 ± 6.5 years (maximum, 25 years). Univariate and multivariate risk analyses for late LVOTO, aortic regurgitation, LVOT reintervention, and death were performed. RESULTS: The early mortality rate was 11% (n = 6); 2 deaths were LVOTO-related. At the latest follow-up, 3 patients (5%) had a LVOTO, 7 (13%) had moderate aortic regurgitation, and 4 (7%) had LVOT reoperation. Actuarial freedom from LVOT reoperation was 90% ± 5% at 10 and 15 years. The mean LVOT peak gradient was 3 ± 9 mm Hg at the latest follow-up. A preoperative pulmonary valve z-score of less than -1.7 (odds ratio, 19; p = 0.02) and an atrioventricular valve-related LVOTO (odds ratio, 15; p = 0.02) are independent predictors of recurrent LVOTO. A preoperative pulmonary valve z-score of less than -1.8 is an independent predictor of LVOT reoperation (odds ratio, 17; p = 0.03). The LVOT gradient per se and the presence of ventricular septal defect or a bicuspid valve do not influence outcomes. CONCLUSIONS: Long-term outcomes of ASO for patients with TGA and anatomic LVOTO are satisfactory in selected patients. A lower preoperative pulmonary valve z-score and complex multilevel atrioventricular valve-related LVOTO are independent predictors of recurrent LVOTO and LVOT reoperation. TGA/LVOTO patients with pulmonary valve z-score exceeding -1.8 and resectable valvular or subvalvular LVOTO, or both, should be candidates for ASO, regardless of the severity of the LVOT peak gradient.

Intra-abdominal umbilical vein varix associated with fetal cardiac failure: a pitfall to the prenatal diagnosis of α-zero-thalassemia.

Hydrops fetalis related to homozygous α-thalassemia is a rare condition in Western Europe. We report a case of fetal cardiac failure that occurred after a second-trimester diagnosis of fetal umbilical vein aneurysm that was postnatally related to α-thalassemia.

Right ventricular systolic strain is altered in children with sickle cell disease.

BACKGROUND: Several adult studies have shown that sickle cell disease is associated with cardiac abnormalities and premature death. The aim of this study was to use speckle-tracking strain, a relatively load independent parameter, to evaluate systolic left ventricular (LV) and right ventricular (RV) function in a pediatric sickle cell disease population. METHODS: Twenty-eight patients with sickle cell disease (mean age, 10.0 ± 3.6 years; mean body surface area, 1.14 ± 0.27 m(2)) and 29 controls matched for age and body surface area were compared. Cardiac output, LV dimension, wall thickness and circumferential strain, LV and RV longitudinal systolic strain, conventional and tissue Doppler parameters, and pulmonary pressure were assessed. RESULTS: LV cardiac output was significantly higher in patients, as were indexed LV systolic diameter, indexed LV mass, and E/E' septal ratio. Indexed LV diastolic diameter, wall thickness, LV shortening fraction, and global LV longitudinal and circumferential strains were similar in patients and controls. However, their global RV longitudinal strain was significantly lower, although tricuspid annular plane systolic excursion and color-coded tricuspid S-wave velocity were similar. Among patients, 21% had tricuspid regurgitation velocities > 2.5 m/sec, but none had tricuspid regurgitation velocities > 3 m/sec. Indexed LV diastolic dimension and systolic pulmonary artery pressure were significantly higher in patients whose hemoglobin was <80 g/L, but parameters of systolic and diastolic LV function were similar. CONCLUSIONS: In children with sickle cell disease, LV diastolic function is significantly altered, although LV systolic function, evaluated by global longitudinal strain, is normal. In addition, cardiac output is increased, and elevated tricuspid regurgitation velocity is common, whereas it is never found in controls. Most importantly, global RV longitudinal systolic strain is significantly altered.

Echocardiographic right ventricle longitudinal contraction indices cannot predict ejection fraction in post-operative Fallot children.

AIMS: To examine in a population of post-operative tetralogy of Fallot patients, the correlation between right ventricle (RV) ejection fractions (EF) computed from magnetic resonance imaging (MRI) and three echocardiographic indices of RV function: TAPSE, longitudinal strain and strain rate. Indeed, these patients present a pulmonary regurgitation which is responsible for progressive dilatation of the RV. An echocardiographic assessment of the RV function would be very useful in determining the timing of pulmonary revalvulation for Fallot patients. However, these indices are generally based on the ventricle contraction in the long axis direction which is impaired in this population and does not seem to correlate with the EF. METHODS AND RESULTS: Thirty-five post-operative tetralogy of Fallot patients and 20 patients with normal RVs were included. In both groups, RVEF, assessed by MRI, was compared with the three echocardiographic indices. Longitudinal strain and strain rates were computed both on the free wall and on the whole RV. No correlation was found between the echocardiographic indices and the MRI EF in our Fallot population. The accuracy of those indices as a diagnostic test of an altered RV was low with Younden's indices varying from -0.18 to 0.5 and areas under the Receiver Operating Characterictic (ROC) curves equal to 0.54 for tricuspid annulus plane systolic excursion, 0.59-0.62 for strain and 0.57-0.63 for strain rate. CONCLUSION: Three conventional echocardiographic indices based on RV longitudinal contraction failed to assess the EF in our population of post-operative tetralogy of Fallot patients.

A new surgical technique for transcatheter Fontan completion.

OBJECTIVES: Patients with complex congenital heart defects and univentricular heart usually required multiple palliative surgery aiming to separate pulmonary and systemic circulations. Various groups work on trying to perform the Fontan completion by a transcatheter technique. We developed and report here a modified technique to prepare the patient for this type of procedure. METHODS: Sixteen sheep were included and prepared through a midline sternotomy. Preparation for transcatheter completion was performed using specially designed devices. The superior vena cava (SVC) was connected to the pulmonary artery (PA) using a Goretex conduit. The connection between the SVC and the right atrium (RA) was interrupted using a vascular stent occluded in the middle by a polytetrafluoroethylene (PTFE) membrane. Two nitinol rings were placed around the inferior vena cava (IVC). Immediately after preparation, the transcatheter completion was performed by first perforating the membrane of the occluded stent and by placing covered stents from IVC rings to the SVC stent. RESULTS: Creation of the SVC to PA connection was uneventful. The insertion of the rings was done successfully in all animals very easily. All stents but one were completely occluding the SVC. Once, a tiny leak was noticed and successfully treated by additional stitches around the stent. Perforation of the membrane was done successfully in all animals re-establishing the pathway between the SVC and the RA. After dilatation of the stent, one animal required surgical control of a haemorrhage related to disruption of the SVC anastomosis. Three to four Cheatham-platinum (CP)-covered stents were necessary to complete the Fontan-like circulation. In the first animal, one stent moved downward missing its target. The placement between the two rings was easily performed using fluoroscopic guidance. No stents were positioned above the SVC stent keeping this part free of material. CONCLUSIONS: We describe new improvements for surgical preparation for transcatheter completion of partial cavopulmonary connection. For superior connection, we developed an occluding stent that helps to re-establish RA to PA connection, alloys precise placement and enhances the stability of the completion stents. Inferiorly, anchorage of the covered stents is also improved by the use of nitinol rings.

Laronidase for cardiopulmonary disease in Hurler syndrome 12 years after bone marrow transplantation.

A patient with severe mucopolysaccharidosis type I (Hurler syndrome) underwent bone marrow transplantation twice (at the ages of 2 and 2.5 years), both times with his HLA-identical heterozygous brother as the donor. Between the ages of 10 and 14 years, despite 92% donor engraftment and 50% normal α-L-iduronidase activity, he developed progressive respiratory failure with severe pulmonary arterial hypertension, upper airway obstruction, and interstitial lung disease. Noninvasive ventilation and weekly laronidase therapy were initiated. Within 24 months, his mean pulmonary artery pressure was within the upper limit of normal and interstitial lung disease and airway obstruction improved markedly. He went from using a wheelchair to having full ambulation, he no longer required daytime ventilation, and his quality-of-life scores (Child Health Assessment Questionnaire) significantly improved.

Right ventricular failure secondary to chronic overload in congenital heart disease: an experimental model for therapeutic innovation.

OBJECTIVE: Mortality and morbidity related to right ventricular failure remain a problem for the long-term outcome of congenital heart diseases. Therapeutic innovation requires establishing an animal model reproducing right ventricular dysfunction secondary to chronic pressure-volume overload. METHODS: Right ventricular tract enlargement by transvalvular patch and pulmonary artery banding were created in 2-month-old piglets (n = 6) to mimic repaired tetralogy of Fallot. Age-matched piglets were used as controls (n = 5). Right ventricular function was evaluated at baseline and 3 and 4 months of follow-up by hemodynamic parameters and electrocardiography. Right ventricular tissue remodeling was characterized using cellular electrophysiologic and histologic analyses. RESULTS: Four months after surgery, right ventricular peak pressure increased to 75% of systemic pressure and pulmonary regurgitation significantly progressed, end-systolic and end-diastolic volumes significantly increased, and efficient ejection fraction significantly decreased compared with controls. At 3 months, the slope of the end-systolic pressure-volume relationship was significantly elevated compared with baseline and controls; a significant rightward shift of the slope, returning to the baseline value, was observed at 4 months, whereas stroke work progressed at each step and was significantly higher than in controls. Four months after surgery, QRS duration was significantly prolonged as action potential duration. Significant fibrosis and myocyte hypertrophy without myolysis and inflammation were observed in the operated group at 4 months. CONCLUSION: Various aspects of early right ventricular remodeling were analyzed in this model. This model reproduced evolving right ventricular alterations secondary to chronic volumetric and barometric overload, as observed in repaired tetralogy of Fallot with usual sequelae, and can be used for therapeutic innovation.

Health-e-Child project: mechanical dyssynchrony in children with dilated cardiomyopathy.

OBJECTIVE: Left ventricular mechanical dyssynchrony has been poorly studied in the pediatric population with dilated cardiomyopathy. We investigated the degree of dyssynchrony in children with dilated cardiomyopathy using tissue Doppler imaging and speckle tracking strain. METHODS: Twenty-five children with dilated cardiomyopathy were compared with healthy subjects. Left ventricular mechanical dyssynchrony was assessed by speckle tracking strain and tissue Doppler imaging. Both radial and longitudinal dyssynchrony were analyzed. Left ventricular end-diastolic diameter was measured to assess the relation between dyssynchrony and ventricular function and remodeling. RESULTS: Radial and longitudinal dyssynchrony parameters were significantly higher in the dilated cardiomyopathy group and correlated with Z-score left ventricular end-diastolic diameter. A logarithmic correlation between left ventricular ejection fraction and left ventricular end-diastolic diameter parameters was found. CONCLUSION: In children with dilated cardiomyopathy, tissue Doppler imaging and speckle tracking strain allowed the detection of dyssynchrony, which correlates with the severity of left ventricular function.