Bertrand Stos

Off-Pump Replacement of the Pulmonary Valve in Large Right Ventricular Outflow Tracts: A Transcatheter Approach Using an Intravascular Infundibulum Reducer

We report our experience of pulmonary valve replacement in animals with large right ventricular outflow tracts (RVOTs) using a percutaneous approach. We intended to implant a device to percutaneously reduce the diameter of the pulmonary artery (PA). Following its insertion, we intended to implant a valved stent inside the restriction. Animals were killed acutely (group 1, n = 6) and after a mean follow-up of 1 (group 2, n = 3) and 2 mo (group 3, n = 9). In group 1, all reducers were successfully deployed and allowed the reduction of the PA to a diameter of 12-mm. In one animal, the proximal part of the reducer did not reach its final configuration. Another reducer embolized when manipulating the stiff wire. The insertion of valves was therefore possible in 17/18 animals. One animal died from an arrhythmia during positioning of the valve. Angiographic evaluations showed no leak between devices and the pulmonary wall. During the follow-up, there was no device migration. At autopsy, reducers were fixed to the pulmonary wall and completely covered by a fibrous tissue. In conclusion, with the use of an intravascular reducer, implantation of a pulmonary valve is possible in sheep through a transcatheter approach when the RVOT exceeds 22-mm in diameter.

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 Youndens 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.

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.

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.

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.

Acute Amiodarone-induced Pulmonary Toxicity: An Association of Risk Factors in a Child Operated by Arterial Switch Operation

Amiodarone is an antiarrhythmic benzoflurane drug with an imposing adverse effect profile. Amiodarone pulmonary toxicity is the major complication. It is well described in adults, whereas it is extremely rare in pediatric patients. This is a case of a child with supraventricular tachycardia post repair of transposition of the great vessels who developed amiodarone toxicity.

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.

Mitral valvar regurgitation in a child with Sweet's syndrome.

We report the very unusual perforation of the mitral valve in the setting of Sweets syndrome, or acute febrile neutrophilic dermatosis, in a boy aged 5 years. Surgical repair was uneventful, and follow-up showed no residual anomalies. Acute or delayed valvitis, with damage to either the mitral or aortic valves, should be screened for in this rare disease.

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.